Custom affordable Tilton clutches available

[JackM]

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We are now offering our own Tilton twin 7.25" clutches to the public. The units are $1200 with OEM flywheel exchange and are far easier to drive than the other twins available for that price range. We can make them for FWD and AWD 6-7bolt applications. These are time consuming to make, so even though we try to keep them in stock they go very fast. It can take up to 30 days to make one, so please be patient. These units are remanufactured by us. Other than the disks they are NOT brand new units! If they were, they would be 2x the price. http://i98.photobucket.com/albums/l251/GVR4_1670/DSC02391.jpg

What makes ours better:

1) We machine the factory flywheel to fit the Tilton basket assembly. This makes installation a breeze in that you don't have to modify or find shorter flywheel bolts, or find a plate to install. You just pop in factory flywheel bolts and it's done.

2) The flywheel isn't used as a friction surface for the disk. The flywheel has a removable plate that is cheaper and easier to replace when the unit is worn out and needs service. This unit, unlike the others is 100% serviceable. http://i98.photobucket.com/albums/l251/GVR4_1670/DSC02392.jpg

3) The Tilton disks that we use are lighter and thinner than the others which means that your trans will shift even faster! There is no RPM limit to this clutch! Go as high as you want and your synchros will love it!

4) You don't have to use an Isuzu slave.

5) You don't have to grind down your throw-out bearing fork.

6) You can use a factory Mits TOB.

7) It runs quieter and engages smoother.

8) The 'friction zone' is almost twice as much with this unit than the others which makes this clutch very easy to drive (the friction zone is the area where the clutch creates friction and the car starts to move). Other twin disks are difficult to drive on the street and considered to be what some call an ON/OFF switch, but ours is a lot easier in that it is not a switch and acts very much like a single disk clutch.

9) Our Tiltons are the easiest twin to drive on the street.

10) You don't have to modify or take apart your TOB.

11) Unit is a lot quieter than the others.

Installation tips:

None needed as they drop right in! The only thing you may need to do is shim your TOB pivot ball. When you install the trans make sure the TOB fork is sitting in the center or slightly to the right of the opening on the trans bell housing. If you do need to shim the pivot ball be sure to check the clearance between the fork and clutch basket to be sure they do not touch.

The bad about twin disk 7.25" clutches:

1) If you are not careful you can break drivetrain parts. These have no give! If you let go too quickly you can easily break something.

2) They are small so they get hot very quickly. Staying out of the friction zone (don't ride the clutch) will give you long life. These can be driven on the street, but care needs to be taken in not overheating them.

3) This is a race part that can be destroyed in one day if the driver is terribly abusive and doesn't know how to treat a multi disk clutch! There is no warranty on a race part like this! We do, however, warranty against defects on our fitment and machining of the unit.

Rumors:

1) A factory machined flywheel will blow up! This is FALSE! People that say this have no clue what they are talking about. These flywheels have no outer mass. What blows flywheels apart is excessive mass on the outer area of the assembly. A flywheel that is heavy on the outer edge will create serious centrifugal forces on the unit and eventually it can fatigue and blow apart. Pictures you see of blown flywheels break because of this. If there is no mass, there are no forces to pull the unit apart and break it! Factory flywheels have been machined for Tiltons just like this one on Fiats, Alfas, Porsches, etc for years and they have run at 9k+ RPMs at Road Race events with no issues. We have tested ours in several vehicles before making these available to the public and no issues at all. They are reliable!

2) The thinner Tilton disks will not live as long. FALSE! The service limit of our thinner disks is the same as the other twin disk 7.25" units available. We don't understand why the others use heavy and thick disks if they have the same service limit.

Questions or comments? Please either call, email or post here. Thanks!

Jack

[JackM]

Here is another thing we are now making more widely known too and added to the site:


WEIGHTLESS CRANKS FOR THE DSM AND EVO!

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We are now offering our weightless 4G63-4G64, 88-100MM, 6-7bolt crankshafts to the public. These cranks have been modified to run without weights. This means that they are the lightest cranks in the World for the 4G63! The 88MM cranks weigh 19.5lbs and 100MM weigh 21.5lbs! These are factory forged cranks which can handle the power and RPM with no issues! $450 with exchange. These cranks will need to be balanced by your local machine shop with your rotating assembly unless you give us your clutch, pistons, and rods and we can balance it for you for an extra $100. These are time consuming to modify, so please be patient as it can take up to 2 weeks to complete one. Please note that this is a race part which means there is no warranty! You have to be sure your clearances and assembly is good or this part can fail like any other.

Rumors:

1) A crank with no weights will vibrate like crazy. FALSE! Anyone that says this has no clue how an inline 4 cylinder works. An inline or opposed 4 cylinder engine is a naturally balanced engine. This means that you have two pistons going up and two going down. The weights on 4 cylinder cranks are there for low end torque, not balance. On an engine with a V configuration this would be true as the weights in V style engines are there for balance and are counter weights. Since our engines are not a V style (like a V8) you don’t need them.

2) A crank with no weight will feel ‘buzzy’. FALSE! We have tested these for a long time now and what we have noticed is the vibration is actually less using these than a full weight crank.

3) This makes the crank weaker and it will break. FALSE! I have personally run this crank in my car and I do a lot of road racing in it. My car sits at redline all day long at the track and I have yet to have a single issue with it. We also had a 7-bolt 100MM crank in a 4G64 car and it pushed 700+hp for 10k miles before the bottom end was inspected and no issues with the crank were found.

4) These cranks will chew through bearings. FALSE! Our main and rod bearings always looked as good as new with these cranks and we never had any issues.

5) These cranks will kill low end torque. True. You want a heavy crank and flywheel for low end torque. These light cranks take that away and are harder to drive on the street because of it.

6) Lighter cranks revv faster. True. This crank will allow your engine to revv freely and you will notice a quicker and lighter feel with more response at higher RPM or when under boost. Without all of the extra weight, when the car hits boost the power will come on faster and harder.

7) You have to use an aftermarket harmonic balancer with this crank. FALSE. You can if you want but it is not needed.

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Jack

[Toybreaker]

Got some questions about the clutch set-up.

It looks like replacing the discs/drive plates results in basically a whole new set of friction surfaces. That's a nice feature. :)

However, I'm kind of concerned about the flywheel.

I understand how removing a substantial amount of weight from the outside of the unit will reduce the forces acting on it, but at the end of the day, it's still a cast iron flywheel.

To be honest, that kind of scares me. I've seen one modified flywheel come apart from trackside, and granted the circumstances were different, the result was something I never want to see again.

More to the point, the sanctioning bodies in the classes where this piece may/will be used require a certification.

That's gonna be a deal killer for many people.

Do you have any plans to offer this set-up with a certified flywheel?

I also had a question on the driven disc splines. With unsprung discs, and a short spline section to work with, how do they hold up?

Have you had any ab~normal wear on the transmission imput splines?

I could see how the alignment and concentricity of the crank centerline and tranny imput shaft could really screw with the plates, if there was a mismatch/angularity between the bellhousing and engine. My (limited) experience with unsprung discs shows they have very little flex, and are completely unforgiving of any miss~alignments.

Getting everything lined up/indexed, and in line is definately going to be critical with this set-up, that's for sure!

It looks like the pressure plate columns locate against the spacer disc on the flywheel, but some dowells would index it a little more precisely. They would also take some of the shear load off the hardware, which is always a good thing. (you can thank me later :) )

One other question I had was about the "snubbers" on the pressure plate columns.

That ching-a-ting-ting with the clutch disengaged is only irritating, the grooves that wear into the columns and prevent a smooth drive plate movement on the columns is a more real problem.

I assume that's what the pads are for.

How do they hold up?

Are they replaceable?

It's nice to see people trying new things.

There's most definately a market for a well thought out, bulletproof and servicable clutch package for these cars.

Good luck on your quest to build a better mousetrap!

[v413nc3]

Tiltons come with those pads, quartermasters do not.

[JackM]

If the FW is that much of a concern, I can do an ACT chromemoly unit as well if requested. Price is the same, I will just need an ACT FW in exchange though. I don't believe that any of the QM or PTT FWs are certified either.

I haven't tried to do a fidanza aluminum FW unit. If anyone has an old one they want to sacrifice I can try to see if I can get it to work.

The input shaft splines are obviously going to be under more pressure with the narrower disks, but it's like any other unit with input shaft spline wear. If the input shaft isn't 100% to begin with the disks can easily chew through it. I have seen input shaft splines wear out in single disk units in the past, so anything can happen if inspection of the input splines is not part of the install. We have never seen any input shaft spline failures on any twins EVO or DSM using PTT, QM, ours, HKS or Exedy units.

We are going to look into the dowels, but none of the other units use them either so it's not a big concern right now.

Thanks,

Jack

[v413nc3]

Jack, the QM is SFI certified. No idea about the Tilton flywheel (it's fairly new and they only have a 6 bolt DSM one). I do have the part number for the QM 6 and 7 bolt flywheels if you want to offer them to your customers.

[Toybreaker]

If the FW is that much of a concern, I can do an ACT chromemoly unit as well if requested. Price is the same, I will just need an ACT FW in exchange though. I don't believe that any of the QM or PTT FWs are certified either.

I haven't tried to do a fidanza aluminum FW unit. If anyone has an old one they want to sacrifice I can try to see if I can get it to work.

Good to hear!

The input shaft splines are obviously going to be under more pressure with the narrower disks, but it's like any other unit with input shaft spline wear. If the input shaft isn't 100% to begin with the disks can easily chew through it. I have seen input shaft splines wear out in single disk units in the past, so anything can happen if inspection of the input splines is not part of the install. We have never seen any input shaft spline failures on any twins EVO or DSM using PTT, QM, ours, HKS or Exedy units.

That's good to know.

We are going to look into the dowels, but none of the other units use them either so it's not a big concern right now

Dowells, Dowells, I want Dowells!!!! :D

When I worked in the machine shop, we had a few issues with clutches/flywheels over the years. Not a lot, but almost like clock work, a few would occur every year.

We (almost) never had any issues with the stock stuff, and very rarely had any issues with the high performance stuff that was assembled in house.

High performance motors we machined, and others went on to "assemble" were another story.

Some owner/assemblers complained of vibrations, some had clutch release issues, and some had the flywheels come loose/rattle. Some insensitive louts that ignored the warning signs of impending doom just came in with parts in a box. ( Color them pissed ).

While a portion of the trauma could be attributed to random hardware failures, (mostly due to under/overtorquing), there was a discernable pattern of failures on the higher torque machines.

Many of those engines that had failed clutch systems utilised dowells, and for whatever reason, the dowells were not re-installed during the engine build.

On a stock build, nothing bad seemed to happen, at least in the short term, but some of the higher peformance stuff came apart fairly quickly.

We took the empirical evidence that was in front of us and decided dowells were good.

We started dowelling the higher end builds, and that was the end of the majority of the issues.

It's a safe bet that when the boffins put pen to paper designing the crank flange/flywheel/pressure plate joints they never even dreamed of the power levels that can be made with simple bolt-ons. (The torque of some of the built cars here would really bake their noodle!)

That it works as well as it does is testament to the soundness of the basic design.

Start adding two, three, or even four times the torque load, add some serious heat, severe shock loading/ load reversals, and we now have a recipe for shortening a logrthymic fatigue scale down to just one race weekend.



Having seen the results of a flywheel explosion from trackside, the design of the clutch system is one thing I take very seriously.

It is a zero failure application, and one worthy of the utmost care in design and execution.

While I agree that most of the dsm applications are not fitted with dowells, that certainly doesn't make it right.

Utilising dowells to take the shear load off the hardware can only do good things for the longetivity of the hardware, and the integrity of the joint.

I don't have much hands on experience with the twin disc set-ups, but a quick search showed that some of the higher end set-ups were dowelled. (so there, naner naner :p )

It could be that they liked the increase in hardware life.

Could be they liked the centering effect, which can only do good things for the balance of the entire assembly.

Could be they just liked the elegance in over engineering a piece to take full advantage of every possible positive design feature they could.

Could be they just had an old guy bugging the beejeezus out of them to make the silly things bombproof. :)

[JackM]

Good to hear!



That's good to know.



Dowells, Dowells, I want Dowells!!!! :D

When I worked in the machine shop, we had a few issues with clutches/flywheels over the years. Not a lot, but almost like clock work, a few would occur every year.

We (almost) never had any issues with the stock stuff, and very rarely had any issues with the high performance stuff that was assembled in house.

High performance motors we machined, and others went on to "assemble" were another story.

Some owner/assemblers complained of vibrations, some had clutch release issues, and some had the flywheels come loose/rattle. Some insensitive louts that ignored the warning signs of impending doom just came in with parts in a box. ( Color them pissed ).

While a portion of the trauma could be attributed to random hardware failures, (mostly due to under/overtorquing), there was a discernable pattern of failures on the higher torque machines.

Many of those engines that had failed clutch systems utilised dowells, and for whatever reason, the dowells were not re-installed during the engine build.

On a stock build, nothing bad seemed to happen, at least in the short term, but some of the higher peformance stuff came apart fairly quickly.

We took the empirical evidence that was in front of us and decided dowells were good.

We started dowelling the higher end builds, and that was the end of the majority of the issues.

It's a safe bet that when the boffins put pen to paper designing the crank flange/flywheel/pressure plate joints they never even dreamed of the power levels that can be made with simple bolt-ons. (The torque of some of the built cars here would really bake their noodle!)

That it works as well as it does is testament to the soundness of the basic design.

Start adding two, three, or even four times the torque load, add some serious heat, severe shock loading/ load reversals, and we now have a recipe for shortening a logrthymic fatigue scale down to just one race weekend.



Having seen the results of a flywheel explosion from trackside, the design of the clutch system is one thing I take very seriously.

It is a zero failure application, and one worthy of the utmost care in design and execution.

While I agree that most of the dsm applications are not fitted with dowells, that certainly doesn't make it right.

Utilising dowells to take the shear load off the hardware can only do good things for the longetivity of the hardware, and the integrity of the joint.

I don't have much hands on experience with the twin disc set-ups, but a quick search showed that some of the higher end set-ups were dowelled. (so there, naner naner :p )

It could be that they liked the increase in hardware life.

Could be they liked the centering effect, which can only do good things for the balance of the entire assembly.

Could be they just liked the elegance in over engineering a piece to take full advantage of every possible positive design feature they could.

Could be they just had an old guy bugging the beejeezus out of them to make the silly things bombproof. :)

I will look into the dowels and possibly make them available for a higher end clutch kit maybe, but for now we just want to see how these do. If they sell as good as they have to the locals around Colorado, then we will definitely be putting more time in them and add more 'stages' I guess to the Tilton units so everyone has something to choose from depending on their setup and taste. We are definitely open to ideas on these. If you would like us to make something that you want for yourself let us know. We have the equipment to put as many dowels as you want anywhere and use just about any FW you want.



Having seen the results of a flywheel explosion from trackside, the design of the clutch system is one thing I take very seriously.

We have an employee here that blew a stock FW in his FWD GS-T many years ago. It totaled his car. He knows the dangers of a FW exploding very well. After looking at ours, he is totally comfortable with our FWs. Neglect, improper modifications to the assembly and improper install can blow any clutch up in any car. What kind of clutch was it that blew up in the vehicle you were watching?

People are quick to judge ours without knowing exactly what we do to them or even looking at them in person. How someone can know everything about what we do by a few pics is puzzling to me, but our company wouldn't be where it is if we sold garbage. Those that do come up with judgments about our units would never buy one anyway, so no matter what we do they will continue to attack as they do with everything else we offer. These FWs that we modify you would be unable to recognize if we didn't tell you it was the factory unit. These are not lightened like the FWs were in the past others used to sell. These things have been modified in a way to make them stronger. Taking weight out of the right areas can decrease a huge amount of stress from the unit and that's what we did. In my car I have one of these but mine was one of the first, so it was a little different. Mine had more weight to it on the outer edge and used a single disk. Mine was modified to give me clean shifts on a single disk at high RPM. I beat the hell out of it all year- 08. Just about every weekend I was out racing the car at some track somewhere. The car sat at redline all day long. Compared to the FWs we make now, the one I used last year looks like a boat anchor and if any were to break that would be the one. I still have it on the car and it's still perfect and I am 100% confident that it never will fail. I will be installing the unit in the pics in my car soon though as a single disk clutch still sucks.

This modification of these FWs has been done to other vehicles with no issues as well. A friend has one on his Porsche race car. He has road raced on it for over 20 years and is still on the original unit. Many of the Formula Zetec Series cars around here also have the same setup. None have blown up their FWs and they race a lot more than you do. Many Fiat, Alfa, and Honda powered race cars around here have them and if you think a DSM has harmonics you should see the Fiats, yet not a single one has ever had an issue! This stuff has been done and used in race cars before anyone knew what a DSM was. The people involved with these units are not idiots. Again, we would not offer something that was unsafe. Again, if you want something different, let us know and we can make it for you. What we offer now is not something set in stone and can be changed to meet the customers needs.

Jack

[JackM]

The cast FW deal appears to be a concern for a few people, so this is what we are going to do. I am going to build a steel API rated version of this FW for our Tilton units. I am going to take the cast FW version off the market for now until I get the steel unit going. The price should be the same. Anyone that has any discomfort with their cast unit they are using now please let me know and I will exchange it for a steel one. We want people to feel safe and be happy with our products and even though I feel that these cast units won't be a problem, I will change the setup anyway. I hope to have a new version made with a steel FW in a couple of months. I have a highly respected engineer- Gary M. that has offered to help us design and build an appropriate FW for this setup that will work even better. Thanks,

Jack

[v413nc3]

That's awesome Jack! Post up info when you have it done.

[Toybreaker]

I felt strongly enough about this subject that I shovelled my truck out, locked the hubs in, and came down the hill to talk with Jack face to face.

The cast FW deal appears to be a concern for a few people, so this is what we are going to do. I am going to build a steel API rated version of this FW for our Tilton units.

Thank you for addressing this concern!

I'm sorry I was so hard on you about this subject, but the safety of my friends is very important to me. I want to be sure we always do everything we can to ensure that we all get to drive home from the track


I am going to take the cast FW version off the market for now until I get the steel unit going. Anyone that has any discomfort with their cast unit they are using now please let me know and I will exchange it for a steel one. We want people to feel safe and be happy with our products and even though I feel that these cast units won't be a problem, I will change the setup anyway.

That's a forthright solution, and a very magnanamous gesture.

Re-engineering a product before it fails is the sign of someone who listens to the concerns of customer base, and has their best interests at heart.

The material selection is probably something that could be argued back and forth ad infinum, but in the end it's a moot point.

Many people will take this package to the track ('cept Tyler, he's scared :p ) , and they will have to tech the car.

Hard questions are asked, and the answers given determine if you get to run that day.

At that point many racers will tell the tech people what they want to hear....

I don't mean to keep berating you so much on the subject, but, if I've learned one thing, it's how well the 4g63 responds to basic mods.

We all know the way it works...

We start off with stock cars, but the damn thing runs so good we turn up the boost.


Then it's over... :p

Even though the initial goals are modest, pretty soon it's bigger turbo's... injectors...fuel pumps and regulators...exhaust...(the list never ends. )

By the time a few years have gone by, many people that may have been tempted to buy the base level piece at the beginning of their build may end up putting two or even three time their original target horsepower/torque goals thru the unit.

This has special ramifications and reprecusssions for your clutch package. Because replacing the disc stack renews the friction surfaces, and since the flywheel *shouldn't* be damaged...your base model piece may still be in service years later, when super hero power levels are being developed.

At that point, it's a whole different ballgame.

The heat and shock loadings, as well as the rpm and torque forces the unit will then see will be much higher.

The various stroker/displacement combo's may also have some unforeseen harmonics. Add in solid mounts, balance shaft removal and the like, and there's no accurate way to predict what kind of forces the package will have to endure during it's service life.

The number of cycles will also stretch into territory that has not been explored during your test period. (especially when some of our local track whores get ahold of this unit.)

In my humble opinion, it's best to factor some of these *potential* scenerios/problems into the design parameters now, during the design stage.


A lot of our friends and forum mates will be pushing the boundries of all that is sane again this year.

On these silly cars, the fuel and brake lines are in the line of fire, so to speak.

As long as the cas is turning (and ~2 seconds more), the fuel pumps are a pumpin. On these huge, multiple pump e85 fuel systems many are running, that's a lot of fuel that could be spraying out of a severed hose/filter/hardline (into an engine compartment with a red hot turbo/exhaust system.)

Yes, that's the worst case scenerio, but I don't even want to think of what *could* happen next.

Our hobby can occasisionally have consequences we could never foresee.


People are quick to judge ours without knowing exactly what we do to them or even looking at them in person. How someone can know everything about what we do by a few pics is puzzling to me, but our company wouldn't be where it is if we sold garbage. Those that do come up with judgments about our units would never buy one anyway, so no matter what we do they will continue to attack as they do with everything else we offer. These FWs that we modify you would be unable to recognize if we didn't tell you it was the factory unit. These are not lightened like the FWs were in the past others used to sell.

Jack, my posts in this thread were not meant to be mean or malicious in any way, shape, or form.

There's a lot of vendor bashing around the web these days.

I've often felt that many vendors bring it on themselves by their actions.

There's room for everybody on teh web, but for some reason the tuners are always bashing each other. :(

We see it all over the web, and I'm very thankfull that the mod staff here at CoDsm doesn't allow it.

I've found the best of the best are often very humble, and let their work do the talking. ;)

I am in no way shape or form an expert on the subject of multiple disc clutches, in fact I have exactly zero practical experience with their application to this platform.

This is why I asked the questions I did where you could address them.

Getting constructive imput from your customers is always a good way to develop something you can really feel comfortable selling.

There's some really smart people on this board, and I'm sure if you had asked for imput in the design stage, you could have produced an even better product for testing.

Building a better hamster trap isn't near as good as building a better mousetrap, when the goal is trapping mice.

You have several of these units running around in the beta testing mode, and that's good.

Getting mechanical loading and thermal cycles on the unit is important.

Thing is, in order to verify that you're on the right track, you need a logrythmic number of cycles, under all kinds of conditions to really know where the issues might lie.

Getting extensive beta testing in on version2.0 before releasing the product for sale to the general public will alleviate many peoples concerns.

I am going to build a steel API rated version of this FW for our Tilton units.

I hope to have a new version made with a steel FW in a couple of months. I have a highly respected engineer- Gary M. that has offered to help us design and build an appropriate FW for this setup that will work even better.

Getting more of these out in the beta testing mode would be a good way to see what kind of track history they will have.

I'm a firm believer in putting my money where my mouth is.

If you build them to this spec, I will beta the unit for you in my own personal car. (To properly fill out the data points, you're going to need a data point from the forty horse crowd.)

I would like sprung friction discs, please (what can I say, I'm old :) )

Many people are going to be concerned about driveline coast down noise/grumble, (especially the guys that are going to daily drive this set-up) and a sprung friction disc package *may* minimise the problem. It *may* also cut down the shock loading on the transmission/driveline, which could only do good things for the durability of the driveline.

I may not put much up on the load side of the chart, but I gaurandamntee you I'll stretch the cycles side of the chart. I put more miles on my buckets under more adverse conditions than any three normal people. Living in the back country has it's price

Did I mention it will need dowells? :D

To be honest, I will settle for a "waisted" style stud that pilots/indexes the pressure plate to the flywheel, as it would have many of the same benefits.

I would also suggest that you open this thread up for a discussion of what other options people would like to see.

There's some really saavy people on this board, and they've probably got some excellent imput on what would be good features to have on version II

[Toybreaker]

Me again...

Questions or comments? Please either call, email or post here.

I am doing just that. (be carefull what you wish for :) )

Thanks!

You're welcome!

Your design intrigues me, so I'm gonna bend your ear about it before I give up any hard earned coinage, capische?. ;)

I was pondering the best way to remove weight from the unit at the outer edges, beyond the bottom plate diameter.

I see that version 1.0 had oblong slots.

I wonder if round holes would be better for achieving a more uniform stress distribution around the outer periphery?

Even better would be to have one of the boffin types run a finite ellement analysis. (heh... I can't even speeel f.e.a. :o , ), so that no uneccesary material is used. That way, no lightening holes would be required.

In addition, I'm curious if a little tweeking to the shape of the various components could gain some aerodynamic benefits. Specifically, I wonder if some subtle shaping could move some air accross the friction surfaces to lower their operating temps. The ultimate evolution of that idea would be to have vented floaters...even of it's just some holes drilled radially thru the floaters, moving some air thru there *may* have some benefits. If they were drilled at an appropriate angle, hot air could be pulled from the center of the unit out...Their limited thickness may make that impractical, but maybe some slots cut accross their surface at an angle would have the same effect.

Combined with some thought to putting an angle on the friction segments (pucks) (that would also move air out from the center of the disc stack), and there *may* be something to be gained there.

Many of the twins that I have looked at during my research had zorched floaters.

I can't help but think much of the friction surface damage occurs off the track. Pulling back into the trailer, for instance. Being able to shed some of that thermal load with improved friction surface ventialltion under higher duty cycles *may* help alleviate that. At the very least, it *might* make the system more consistent on back to back runs.

editI dunno...it may also make the whole thing taco up like a big ole belleville warsher... ;)



As I've said before, I am not an engineer by any stretch of the imagination. (I don't even play one on the intraweb :) ), and I have no idea how many (if any) of my concerns have any basis in reality.

I've always felt that the clutch system is one of the achilles heels of these cars. (the left achilles heel, to be exact... ;) )

Shock the driveline, and **** breaks (or it shocks the tires and spins all thru way thru the gear.)

Slip too much, and you got a barbeque in the bellhousing.

A soft hitting, progressive lock up clutch like the top fuel guys run would fit the bill, but it's going to be a cast iron ***** to get that stuffed inside the bellhousing. (wanna get on that for version III? :D )

Balancing the co-efficient of friction of the clutch disc against pressure plate clamping force is an art and a science, and I can't even pretend to have a grasp on the engineering that goes into that.

A quick search of the web for dsm clutches will give a veritable corucopia of choices...and then some!

Organic, carbon, kevlar, semi metallics, metallics, ferro ceraman~to~liciousous... the list just goes on and on...after a page or two, the eyes just glaze over...

Just when we decide to just order up another act or (whatever)...we start looking at the available configuration choices...street, strip, race, sprung, unsprung, full surface, 4 puck, 6 puck, a dozen....

AAAAAghhhhh!

So many choices!!!

It's enough to drive you seriously, fully, completly bonkers

Your package with it's modular design has some serious potential.

Many twin discs have *most* of this feature, but the flywheel friction surface still needs to be addressed each time the disc stack is changed.


With your design, simply changing the disc stack, results in all the friction surfaces are renewed.

This means a completely different package can be built on the same foundation.

That's a really neat feature, and in the long run, it could save cheap bastids like me some cabbage.

Good luck with this project, and please keep us updated on your quest to build a better mousetrap

[thiazole]

Even better would be to have one of the boffin types run a finite ellement analysis.

This whole idea might be overkill, but if anyone does have any interest in metal composition analysis, I used to know of a lab in Ft. Collins that is probably still there (and there might be more out there) that does this using x-ray fluorescence (I think). I don't think they charge very much to do it - maybe $50, maybe even less. Their main customers want to know how much gold is in their jewelry, so if they charged too much, they wouldn't have customers.

[v413nc3]

My god, after I read John's book, and took a nap, at lunch and had time to re-read it :-p


Seriously though Jack. That's awesome. Get us the info on it. I probably won't run it because I'm going to carbon/carbon soon but your kit will become one that I recomend to others.

[sbiggi]

Good decision Jack. With the steel flywheel, you can easily compete with the TwinDisc's that are currently on the market too.

[JackM]

Okay, Gary and I went around town this morning and know what we need to do (he already knew, he was just showing me). Gary is pretty awesome because he came down and 'looked' at the flywheel in person to give us his true metallurgical engineering view point of the unit which he disliked. He didn't post on private boards, he didn't make assumptions via pictures only, and he didn't come in yelling at everyone. What he did was just totally awesome and I respect him in doing it yesterday, and today for helping us out in making a unit that will be not only very safe, but work perfectly too. What is really nice about all of this is we have everything we need right here in C/S so that's going to make things a little easier. The Operations Manager at an ISO9001 certified CNC shop here is willing to do the 6-7 bolt AWD version of the FWs for us (which is great because many CNC shops with the capabilities of doing these things don't want to waste their time on stuff like FWs). We believe the best material for now is going to be 1045 annealed steel plate. We may treat it after it's done, not sure on that yet. If it is something we will treat then we will have to make sure we have tolerances set up for that as additional machining will be needed again. I hope though that we won't have to treat it as that will save on time and costs. The nice thing about our Tilton setup is it's a badass Tilton unit for the price of the lesser units, so I want to keep the costs down if possible to continue to make it affordable for all.

The thing that looks to be the biggest pain is going to be the SFI testing and license agreement. What we decided to use for metallurgical material appears to be acceptable by SFI standards. The cast (gray) iron we were using/testing is not. For kicks I was going to see if it would pass, but they will not certify it even if it did pass the tests. I hope that we can get away with a test bar sample instead of testing via apparatus. For rotational integrity testing I figure the max rotational speed these units will see will be 11k RPM. I can't imagine anyone going over that. They will need to test it at 150% of that, so I figure that's more than enough. If any of you think you will be going over 11K RPM for whatever reason please let me know and I can certify it for higher.

I hate this SFI deal as it looks like such a pain to work with, but after it's all done we will only have to worry about it every 2 years, so hopefully these things will sell well enough to make this worth it. I hope that those that squawked over this SFI deal will possibly consider one of our units when this is done, as we are doing this to please you guys. I really hope that the SFI griping wasn't just some way of bashing my product with no intention of buying it either way.

The FW will be of our own design. It will be a unit capable of not only using a twin disk Tilton basket assembly for the DSM, but it will also be able to fit a 3 disk unit as well! It will bolt right up to the crank just like the factory unit with no shortened bolts, adding plates, etc. You will not have to grind down your TOB fork either. The friction zone will also continue to be very wide just like the units we have tested so far to keep drivability nice if used on the street (won't be an ON/OFF switch). The only inconvenience of these new FWs is going to be the starter ring gear. It will have to be swapped over from your FW over to the new one. I am hoping after these initial costs that we will be able to continue to sell the refurbed Tilton assemblies for the same $1199.99 price.

I hope to have all of this done very quickly. We got a pretty huge response from these through the website, so I think this is a worthy risk on our part to take. If you have any questions about any of this stuff please feel free to ask. If you have any input on anything you would like to see added to the unit also, please post. Thanks!

Jack

[thiazole]

My honest opinion is that this will end up being bigger than your transmission business. Everyone has to buy a clutch eventually and the installation hassle and decreased drivability is a lot of what keeps people away from the other twin disks out there (people might think cost, but for a good single disk clutch that can hold that much torque, it will still cost >$500 and will likely need serviced a lot more often at $150/disk and the labor making the real cost very similar). If you solve that (which you have) and offer it for the same price then you win the game. Offering this in the middle of a recession might work out for the best just because it will give you some time to develop the capacity to crank these out. You might already be overwhelmed by the response once you get this final product on the shelf.

[JackM]

What Gary and the CNC guys were nice enough to point out in person about the cast FW are the following flaws:

1) Taking material off the surface of a cast FW will modify a metal component with a hard and fatigue resistant surface, but soft core, and make it weaker. If this hard surface is removed during the lightening process then this will seriously weaken the flywheel and could result in the wheel coming apart.

2) We left the center inner area of the FW alone to keep this hardness and we lightened only the outer part of the unit so there is less chance that the unit would fail. This doesn't work in a cast FW as the hardened area may hold, but the modified outer area will not over time. They have seen FWs come apart with he center still fully intact (oh, did I say these CNC guys were also into auto racing and car their own cars as well? :) ).

3) The kidney shaped holes we have on the outer edge of the FW makes this worse as that whole area is weaker due to the fact that stress cracking can more easily work it's way from the hole edges to the bolt hole threads and other sharp edges in that area. They say that just a bump or chip from a ratchet can now start a crack that can kill the unit.

4) It's still heavy and difficult to machine/make. A steel unit is not only capable of getting SFI certified but is also less time consuming on our end, made of better materials and can be a lot lighter than the cast unit could ever be.

Jack

[JackM]

Thanks, Thiazole! I would like to swap your cast FW to our new steel SFI approved unit when it's done. I appologize for the inconvenience on your end, but I think it's a worthy upgrade for you. It will all be free- no charges on your end.

Jack

[Cloud]

I really want to get a decent clutch setup at some point but I have some issues with current twin disk setups. I drive a street car, I beat the piss out of it, I avoid 'race only' parts because longterm durability is just as important to me as power handling capacity.

Are there other twin disk (or otherwise) setups that offer easier engagement of a sprung full disk, still have a light pedal, and will hold up well under stop and go engagement in traffic, etc...?

Also just wondering, but why was aluminum not considered (or if considered, not selected) as a replacement material in this re-design?

[JackM]

Cloud, the reason I have not wanted to use aluminum is due to the fact that I am new at FW design here and would rather start off with a material that is easier to deal with and more forgiving. Wrought aluminum is an acceptable material for SFI approval, but I would rather keep it simple for now.

I think the best unit for your needs would be a carbon Tilton. That will give you what you want, but they are expensive.

Jack

[thiazole]

Thanks, Thiazole! I would like to swap your cast FW to our new steel SFI approved unit when it's done. I appologize for the inconvenience on your end, but I think it's a worthy upgrade for you. It will all be free- no charges on your end.

Jack

I was thinking one of your transmissions will probably be the next (and hopefully last for a while) upgrade, so when I pull the trigger on that we can swap flywheels. That will probably be later this year.

[v413nc3]

Jack, I'll pimp the **** out of this for you when you get it finished. It sounds like a well thought out and well rounded approach. And for what it's worth I have an engine I'm working on that we're going to try 13kRPM. If you're up around here sometime I'd love for you to take a look and tell me what you like/dislike about it.

[JackM]

Okay, cool! Seems like a lot more people are going higher in RPMs these past couple of years so maybe we will see if we can go that high then. I have a feeling though that a certified FW would need more work for that RPM...

Jack

[XakEp]

I've been off in CCIE prep land, so when I read about this I just sat back and clapped quietly. Jack, you're going to have alot of success if you just keep being yourself and doing what you've been doing all along. Don't let the little people get you down. This is as true now as it was when I met you what, 8 years ago? :)

Congrats, and good work! Success couldn't happen to a better person.

[XakEp]

Jack was referring to people on other forums, not you - specifically the DSMlink forums. There are a few forums where the people just jump on him or his ideas because they can. Dont sweat it. This is an example of the horse**** that someone posted elsewhere about his cranks.

i dont think i would let jack go within 500 feet of my car with all the bull**** he feeds everyone on all the forums...

[Toybreaker]

Jack was referring to people on other forums, not you - specifically the DSMlink forums. There are a few forums where the people just jump on him or his ideas because they can. Dont sweat it. This is an example of the horse**** that someone posted elsewhere about his cranks.

Thank you very much for saying that!!!

I'm not on that board, so I don't know what is said there.

As far as this deal , I apologise to this whole board, and all the members who had to read my long posts on the matter.

I take my obligations seriously, and I will do whatever I can anytime I can to contribute information that will result in safer racing.

I see real potential with this design, and with some input from the people who are going to be running it in the beta mode, I'm sure all the bugs will be worked out for version2.0

In the end, that's all that matters. :)

[v413nc3]

I personally bust Jacks balls because I *know* for a fact that he can do better sometimes. This was one case, and he is proving that he will redesign a better flywheel. Just like anyone else if he doesn't have someone ride his backside about things then he'll get complacent. It's better to get him fired up and watch him engineer a bigger better mouse trap :) In the end the community is better for it, if not his blood pressure.

[prophecymiller]

This is really awesome! I hope this works out great for you Jack! And I'm positive your time has been a help for revising this unit to be the best Toybreaker.

One question- this may sound redundant, but what would be the benefits of running this unit vs. another ACT for a pure street car? I am asking because I hardly know anything about clutches, much less a multiple disk, but I do really like how these are serviceable and look to be smaller in diameter than a typical single disk.

EDIT: I should rephrase my question- You mentioned some benefits of this clutch but they were in comparison to other twins...what I want to know are the benefits of this unit over a single disk street setup? Maybe you could expand a little or someone else who knows could put it out there.

[thiazole]

I think it is more streetable than a super high pressure single disk (less pedal pressure for sure) and shifts way better and faster than ANY single disk. Using DSMLink to time how fast I can shift gears, I can now shift in less than half the time it took me with my SPEC. Twin disks will also shift MUCH better at high rpms than single disk clutches.

[D Walker]

Okay, Gary and I went around town this morning and know what we need to do (he already knew, he was just showing me). Gary is pretty awesome because he came down and 'looked' at the flywheel in person to give us his true metallurgical engineering view point of the unit which he disliked. He didn't post on private boards, he didn't make assumptions via pictures only, and he didn't come in yelling at everyone. What he did was just totally awesome and I respect him in doing it yesterday, and today for helping us out in making a unit that will be not only very safe, but work perfectly too. What is really nice about all of this is we have everything we need right here in C/S so that's going to make things a little easier. The Operations Manager at an ISO9001 certified CNC shop here is willing to do the 6-7 bolt AWD version of the FWs for us (which is great because many CNC shops with the capabilities of doing these things don't want to waste their time on stuff like FWs). We believe the best material for now is going to be 1045 annealed steel plate. We may treat it after it's done, not sure on that yet. If it is something we will treat then we will have to make sure we have tolerances set up for that as additional machining will be needed again. I hope though that we won't have to treat it as that will save on time and costs. The nice thing about our Tilton setup is it's a badass Tilton unit for the price of the lesser units, so I want to keep the costs down if possible to continue to make it affordable for all.

The thing that looks to be the biggest pain is going to be the SFI testing and license agreement. What we decided to use for metallurgical material appears to be acceptable by SFI standards. The cast (gray) iron we were using/testing is not. For kicks I was going to see if it would pass, but they will not certify it even if it did pass the tests. I hope that we can get away with a test bar sample instead of testing via apparatus. For rotational integrity testing I figure the max rotational speed these units will see will be 11k RPM. I can't imagine anyone going over that. They will need to test it at 150% of that, so I figure that's more than enough. If any of you think you will be going over 11K RPM for whatever reason please let me know and I can certify it for higher.

I hate this SFI deal as it looks like such a pain to work with, but after it's all done we will only have to worry about it every 2 years, so hopefully these things will sell well enough to make this worth it. I hope that those that squawked over this SFI deal will possibly consider one of our units when this is done, as we are doing this to please you guys. I really hope that the SFI griping wasn't just some way of bashing my product with no intention of buying it either way.

The FW will be of our own design. It will be a unit capable of not only using a twin disk Tilton basket assembly for the DSM, but it will also be able to fit a 3 disk unit as well! It will bolt right up to the crank just like the factory unit with no shortened bolts, adding plates, etc. You will not have to grind down your TOB fork either. The friction zone will also continue to be very wide just like the units we have tested so far to keep drivability nice if used on the street (won't be an ON/OFF switch). The only inconvenience of these new FWs is going to be the starter ring gear. It will have to be swapped over from your FW over to the new one. I am hoping after these initial costs that we will be able to continue to sell the refurbed Tilton assemblies for the same $1199.99 price.

I hope to have all of this done very quickly. We got a pretty huge response from these through the website, so I think this is a worthy risk on our part to take. If you have any questions about any of this stuff please feel free to ask. If you have any input on anything you would like to see added to the unit also, please post. Thanks!

Jack

Good job!

[Mr. Moose]

I'm excited for your progress, Jack! When you get this figured out, there will be tons of demand, I predict.

[matthewdesigns]

Jack, you need to edit the "DSM Clutch Selection" page on your website, now that you build the best twin disc around.

Over 500HP AWD or FWD: It is highly recommended to go with a 7.25” twin disk clutch from PTT or QM. An ACT 2900 with a 4-puck can go as high as 600HP, but it is so hard to push the clutch pedal in at that point and they drag so badly at high RPM that it’s just stupid to run it. The PTT and QM units will hold all the power you want and shift at any RPM.

[JackM]

Thanks, I will have our own section eventually for our twins and 3 disk units. My main focus right now is getting the FW setup straight first.

Jack

[JackM]

Update:

I'm a little rusty with this CAD software since I haven't used it in 11 years, but it's coming back to me. Have it all done for the most part, but on a few spots I need measurements that my instruments are too small to get for me (like the outer starter ring gear surface), so I will need to take it somewhere else for those measurements and all should be good to go. I am going to have a friend double check my work to be sure all is really correct and then from there off to the CNC it goes! I am a little behind (wanted to have this done this weekend) but it's getting there...

Oh, and I could not get a 3 disk setup to work. Got it to fit in the basket and in the car perfectly, but the input shaft is too short. The splines on the 3rd disk are unable to make good contact with the input shaft, so a 3 disk version is going to have to hold off for now.

Jack

[v413nc3]

That's what we've seen with other setups too Jack, Other than machining a longer input shaft (maybe with a pilot bearing even though we don't need it) I don't see a good way to do it. It sounds like you're going to cut the flywheel with the ring gear as part of the unit. That would be good because we're stuck welding ours on right now (we've had them come off) and them balacing them. Nice to hear progress!

[JackM]

Yeah, I hear you on the ring gear. I am kind of torn on that one right now. I can have one made that is thick enough where I can use bolts to hold it in place, or I can just use the OEM gear. I don't want to cut into the OEM ring gear though as it is too thin and I am afraid that it might break if I weaken it with the bolts to secure it.

What I am going to try first with this unit I am building now is have the OEM ring gear press into place and then have 3 bolts spaced evenly around the unit hold it in place via a large head on the bolt. The gear should press in tightly, so it shouldn't be a problem, but just in case I am going to try to have bolts in there to prevent it from popping off. The bolts will thread into the flywheel but the head will be up over the gear just enough to prevent it from working its way out. I'll see how that looks, if it doesn't look good them I may have to go the thicker custom made ring gear route which I want to avoid...

Jack

[v413nc3]

The flywheels Erron just got for the 3S twin had it integral to the flywheel. I'd hit him up for a picture. That might be a route for you since you're going to get them cut it would just be a small extra step. The current one for the QM presses on and is very tight but it still can come off. It's not very often though.

[JSMCPN]

Safety first. All else being equal, Mitsu's tooling/measuring is probably more accurate :D

[BlueVelocity]

The flywheels I had made from CRMO just as a reference..
http://img90.imageshack.us/img90/8269/flywheelfgb0.jpg

Ring gear tigged before balancing...
http://img90.imageshack.us/img90/4476/dscf0011rx5.jpg

[JackM]

Cool, thanks for the pics! My worry is the common customer may not have access to a TIG so I'm trying to make this gear an easy swap for them if possible.

Yours looks very similar to mine. I'm trying to keep it simple but keep coming up with more stuff I want to add to it to make the system more badass, but I just need to stop and try it like it is though...

Another thing that I was working on was having a slightly recessed area for the baskets mounting point on the flywheel. Instead of using a dowel, having a nice snug spot where the leg of the basket can fit into might be better. It would help center it too.

Unfortunately, the more you add to the machining process the more expensive to build. I guess I'll have to check pricing on all ideas to see if it's economical to do.

Thanks again for the info!

Jack

[JackM]

Safety first. All else being equal, Mitsu's tooling/measuring is probably more accurate :D

You'd be surprised how everything measures out to a nice metric even number for this stuff... Mitsu was very kind in making things simple. I would be willing to bet the outer ring gear surface on the FW is also a nice simple number. Even the basket measured out to be something simple. This stuff looks to be pretty easy so far, I'm surprised more people haven't made stuff like this.

I'm not sure how BlueV got the correct measurments for the odd bolt pattern of the 3S crank, but bravo on that one :)

Jack

[BlueVelocity]

I'm not sure how BlueV got the correct measurments for the odd bolt pattern of the 3S crank, but bravo on that one :)

Jack

Thanks Jack. I'd love to take credit for it, but it was Jake that took the measurements. :D Hit the nail on the head with that one, it could not have turned out better. Not only that, but he also precisely measured out the correct spacing for the hydraulic throw out bearing. Needless to say it was fun watching him and Marcus do SAE to Mil conversions in their head. (I cheated and used a calculator, lol) We must have measured it 15 times. Came out the same every time, but we still measured 15 times. :p

[v413nc3]

Yeah, well after the fiasco of pulling my transmission 8 times to get the damn HToB to work right I figured measure a thousand times, put the heavy trans in once. I never make the same mistake twice, but damned if I don't make new ones constantly.

[v413nc3]

You know Jack, I have some cool shouldered ARP studs that locate the clutch covers without use of a dowel. If you want I can snap some pics of them.

[JackM]

Okay, finally got all of the CAD work done. I was sick for 2 weeks and that pushed me behind on other things so I had to set this to the side for awhile. Here are some pics of it:

http://i98.photobucket.com/albums/l251/GVR4_1670/DSC02960.jpg

http://i98.photobucket.com/albums/l251/GVR4_1670/DSC02961.jpg

http://i98.photobucket.com/albums/l251/GVR4_1670/DSC02962.jpg

Looks like due to simplifying the design it will be economical to build. It's going to be 20-30 days for the CNC to be done with them and then off the get SFI approved they go. I'll update as things progress.

I intentionally made this FW a little heavy. This setup is going to be for a very smooth and kind twin disk system that is easy to drive with a wide friction zone to make it feel like a single disk clutch. The goal is to make the clutch very friendly and not an ON/OFF switch and a heavier FW will help accomplish that. Maybe if these sell well we will come out with a race version, but ON/OFF switches suck to drive so not sure on that one...

Thanks,

Jack

[v413nc3]

Jack, it's looking good!

[JSMCPN]

Are you going to make a 7-bolt flywheel also?

[JackM]

Yes, and I will also build a GS-T FWD 6-7 bolt versions if the AWD units sell well enough.

Jack

[ThePyro1]

Any new updates? I need a clutch soon and was kinda hopeing yours were about set. I have a jun chromoly fw if your still using that stuff

[JackM]

I thought I deleted this thread but:

Hello, I spent over $10k on a set of flywheels, but I goofed on the design and they were too short. The disk on the flywheel end didn’t sit on the trans input shaft fully so there is a risk of damaging the shaft. Other than that they were perfect. I’ll make more, but due to the huge loss in these things we are taking a break from them right now. Everyone using the cast versions still run them and they still work perfectly. It’s too bad, because those Tiltons work and feel so nice! I may have found a better solution though to the clutch drag issues for single disk units. 90% of the people that use twin disks don’t need them and only use them due to the terrible high RPM clutch drag issues single disk units have. I ‘think’ we may have found a solution to this, but I want to test it on my car next season first.

Thanks for your interest, sorry that I was unable to get them set up for you.

Jack

[ThePyro1]

No worry thanks for the time effort, and money you did spend