Stroker Question

[TsiDrummer]

I've done a few searches in a lot of different places over the last few days, and I've been trying to find out if a G4CS crank will work in a 4G63? I have both engine's, and I've been trying to decide if doing a 2.3 stroker will work better than the 2.4 or not, however if the crank won't fit, I guess I have my answer.

What are your thoughts on whether it fits, and which one to do? I want to have a good low and high end power car for daily use and the occasional bandi trip.

Any info and tips/comments are greatly appreciated.

Thanks in advance!

-Eric

[rlarsen]

It will fit in a 6-bolt 4G63 block.

[SecurFocus]

Great subject to start! I recently threw a rod bearing on my 7 bolt...I am now going for the stroker! I am looking at the 2.4l and am getting help from dsm_gsx97 on the motor build as my car is sitting at his house! I would like to here from some of the people who have built one.

what CR did you use 8.5:1? why did you change if you did?
2g head/1g head?

I am in the process of looking at parts to purchase as we haven't done anything yet! its been 2 weeks since my car has gone belly up and am starting to have withdrawls :( thanks for any advice you have to share! Sorry if the question is vague!

[dsm_gsx97]

This is my good buddy Justin who watched us (Kenny, Shawn, Erron and I) for 4 years race DSMs then got the bug once he moved to Seattle *figures*. He was driving (from Seattle) to come visit and get some stuff done to the car and about 50 miles North of Casper, WY his 7-bolt took a dive. He's looking for a summer car that will be fun with some track use. I recommended that he posted here to learn from some of the people that have done the 2.3L or 2.4L conversion. Links I gave him to look into were:

http://www.carotica.com/4g64/index.html

http://www.extremeevolutions.com/

He has a '98 GSX. So first thing I guess to find out from you guys is switching to a 6-bolt necessary because the 7-bolt 4G64's have the same crankwalk issues as the 4G63 7-bolts? I haven't looked into this since I was building a drag motor and stuck with the 2.0L, but I wouldn't think they'd have the same issues so switching to a 4G64 7-bolt seems ideal.

[DSMxTSi]

There's a guy in Co Springs that supposedly has a fix for crankwalk and gaurantees his work or he fixes it free of charge. I don't anything about his shop but his name is Jack and the number is 1-719-243-5305. Someone surely has heard about him around there?

[dsm_gsx97]

There's a guy in Co Springs that supposedly has a fix for crankwalk and gaurantees his work or he fixes it free of charge. I don't anything about his shop but his name is Jack and the number is 1-719-243-5305. Someone surely has heard about him around there?

Yes Jack is a member on this board and has posted about this to us before. Check the old email list archives for info about that. Check out Magnus for some good reading if you want to hear another "fix". But we're not looking for a fix here.

We're asking for stroker questions to find out our best build path considering what we already know. Looks like no one wants to talk about this so I'll go with what I already know from Shawn's 600hp 2.4L beast.

We'll be doing a 7-bolt 4g64 block, Eagle H-beams , Ross pistons. I'm wanting him to go 8.2:1 but 8.5:1 will probably be the route we go and 0.020 over. 2G head for faster spool and 1mm oversized valves to help with flow. HKS272's and all the other bolt on goodies.

[rlarsen]

If you're doing a 2G head on a 2.4, I would suggest doing a bit of portwork. Open up the intake side a little (don't screw up the entry angle too much), clean up the guide bosses, any seat overhang, and knife edge the intake and exhaust dividers. Also, bolt the head to the block and observe the combustion chambers up through the cylinders. Unshroud the valves (should be able to do some good work here due to the larger bore).

Are you building it as a long-rod motor? If not, why not? Is this going to be primarily a pump gas street motor, or much more drag oriented? Are you installing squirters? What turbo are you running? Nitrous?

[dsm_gsx97]

If you're doing a 2G head on a 2.4, I would suggest doing a bit of portwork. Open up the intake side a little (don't screw up the entry angle too much), clean up the guide bosses, any seat overhang, and knife edge the intake and exhaust dividers. Also, bolt the head to the block and observe the combustion chambers up through the cylinders. Unshroud the valves (should be able to do some good work here due to the larger bore).

Are you building it as a long-rod motor? If not, why not? Is this going to be primarily a pump gas street motor, or much more drag oriented? Are you installing squirters? What turbo are you running? Nitrous?

NOW THAT'S WHAT I WANTED!

Right on...so here is the deal.

No nitrous...street driven summer car using pump gas and not E85 because the Seattle area doesn't have any of that except a station or two. We were keeping the 2G head for the quick spool with the runners, but I figured 1mm oversized didn't hurt. We could switch over to a 1G head easy enough because I really don't want to mess with the runners of the head unless you really think its needed.

Long rod motor...to be honest not really familiar with that but am dying to hear about it now. We just were keeping things simple and was looking at a slow boy racing kit. Please explain the benefits for him (and me).

Squirters, well I'm back and forth on that. I didn't do them on my block, but then again my block is a race block. I think for a street driven car I'd probably use them. What's your thoughts on that? Are they even in the 4G64 block? I kinda remember hearing they aren't.

The turbo he just bought before the block went was a EVO3 16G. Still in a box in my basement for him. For now I think he was considering just keeping that, but I told him that ideally he'd want to up that since I'm guessing with a 16G on a 2.4L that you'd be able to squeek the tires in every gear to 4th with how fast that sucker would spool. I'm thinking a FP3052 or FP3065 would be the best in the end.

[rlarsen]

No nitrous...street driven summer car using pump gas and not E85 because the Seattle area doesn't have any of that except a station or two. We were keeping the 2G head for the quick spool with the runners, but I figured 1mm oversized didn't hurt. We could switch over to a 1G head easy enough because I really don't want to mess with the runners of the head unless you really think its needed.
Both heads are great in their own ways. The 2G head has a superior entry angle and in my opinion is the better core to start with when building a quality race head. However, there's certainly nothing wrong with the 1G head, and core for core it certainly flows more in the top end than the 2G. With portwork, the 2G can pretty much match it for top end flow while retaining the superior flow characteristics of the core. If you look at the EVO heads, you'll notice they have more in common with 2G heads than 1G. If you're not doing any portwork, and don't actually need a valve job, there's no point in going 1mm over. If the head needs valves and a valve job, then there's no reason NOT to go 1mm over. Just not something you're going to notice the gains from by itself, in my opinion.

Long rod motor...to be honest not really familiar with that but am dying to hear about it now. We just were keeping things simple and was looking at a slow boy racing kit. Please explain the benefits for him (and me).
It increases the cost a bit (~$1350 for pistons and rods). As far as I know, Magnus is the only company selling the 156mm rods and the 87mm Ross pistons with the offset pin. I'm sure I could get the parts directly from the distributor, but Marco innovated all this stuff and I refuse to go behind his back. I'm happy to do business with him on this stuff (and have bought plenty of long rods and stroker pistons without a problem).

Functionally, you aren't changing anything as far as bore and stroke go, i.e., the displacement stays the same. Where you do gain is that you're using a considerably lighter piston (because of the raised pin), and only sacrificing a slightly heavier rod (which is closer to the rod pin of the crank than the piston). You're also improving the R/S ratio (1.56 instead of 1.50). What does this mean? Functionally, you gain a little reliability, improve cylinder filling, and about 500RPM on the rev limiter. I wouldn't build a 2.4L without strongly recommending the long rod option. Personally, it's the only reason to even bother with the 2.4 blocks (otherwise, just stay with 150mm rods and use a 2.0L block). When building big HP 2.0L, I like to use the long rods and relocated pin pistons as well, for the same reasons as above.

Squirters, well I'm back and forth on that. I didn't do them on my block, but then again my block is a race block. I think for a street driven car I'd probably use them. What's your thoughts on that? Are they even in the 4G64 block? I kinda remember hearing they aren't.
They aren't, but they're reasonably easy to machine in on 4G64's. The G4CS blocks are a pain because there aren't any locating marks for them. If a car is going to be regularly, spiritedly street driven, roadraced, or hotlapped, I won't build a motor without them. For a pure drag motor, they're probably not necessary. My opinion is that the benefits outweigh the potential disadvantages (slight reduction in oil pressure, possibility of them breaking off if they're not clearanced properly on a 100mm crank motor). Also, I try to always use blocks that allow the use of the 1G or Evo style squirters, I'm not a big fan of the 2g style.

The turbo he just bought before the block went was a EVO3 16G. Still in a box in my basement for him. For now I think he was considering just keeping that, but I told him that ideally he'd want to up that since I'm guessing with a 16G on a 2.4L that you'd be able to squeek the tires in every gear to 4th with how fast that sucker would spool. I'm thinking a FP3052 or FP3065 would be the best in the end.

Yeah, on a 2.4L, with decent comp ratio pistons, he's going to spool that 16g like a T25. It will be fun though, until he realizes he's killing the thing trying to make it keep up at high RPMs. If he doesn't want to go full Garrett, those FP turbos would be killer. I know Doug was more than pleased with his 3052 for a pure road racing application with his 2.3L motor.

[dsm_gsx97]

That was awsome. Thank you...looks like me and him have to talk some more over the whole idea and see what he wants to do. This definately paints a better picture for him than just the limited knowledge and few links I had about it. Thanks again.

[buckley]

Well, I guess this is the thread for me as well.

I spun a bearing in my 97 about a month ago and since then I have decided to do a stroker.

Everything is in, I just need to take the motor to Jack to have it built. He does really good work from my experience (fully built tranny).

Anyway, I decided to stick with the 7 bolt, only because Jack will be doing the crankwalk "fix". I am using 2.3l wiseco 8.8:1 pistons, 2.0 eagle h-beam rods, and a 4g64 micropolished crank.

I will be pushing a Garrett 60-1 on a 38 mm wastegate and obviously full fuel (255, AFPR, 950cc). I will also be using dsmlink.

I also decided to stick with the 2g head because of the reason that if I used a 1g, I would need to portwork and mess with entry angles, etc... The 2g head is perfectly fine.

If you are able to contact Jack, I believe you will save some money by just sticking with a 2g and getting a crankwalk fix. You won't have to find a 1g block, pan, oil pump, etc...

Sorry to be talking so much, I just thought it would help hearing it from a guy who is building a stroker at this moment as well...

We'll see how it goes with my car and good luck with yours. Keep in touch!

Adrian Buckley

[dsm_gsx97]

Hey Adrian this Chris (who's house you were at last weekend for the timing belt cover). This car is the one in my driveway we were talking about that looked just like the one in the garage.

I also decided to stick with the 2g head because of the reason that if I used a 1g, I would need to portwork and mess with entry angles, etc... The 2g head is perfectly fine.

Your confused actually...it's the opposite of what your describing...read Ryan's post above again so you see. 1G head doesn't need the extra's of what Ryan says would be a good thing to do to the 2G head to improve flow. So from what he's describing, if your using a 2G head, you'd want to do the port work.

This doesn't mean porting needs to be done to the 2G head, but that it would be a good thing to do.

[rlarsen]

This doesn't mean porting needs to be done to the 2G head, but that it would be a good thing to do.

Doesn't necessarily mean the 1G heads don't need it, either. ;) There's tradeoffs for using either, I just prefer to to start with 2G cores as I believe the casting is generally better designed from the get-go.

[buckley]

Thank you for the correction. Still learning obviously.. :0

buckley

[JackM]

2G head for faster spool and 1mm oversized valves to help with flow. HKS272's and all the other bolt on goodies.

I hope you are going to replace the seats to bigger units as well and are porting the area around the seats with those 1mm over valves. Just about everyone I have seen that uses 1mm oversized valves just grinde the OEM seats to match and all you are doing is just blocking more airflow with the bigger valve head. My brother did that to his head for his 4G64 and I believe that I will kick his butt this year as well with things like those valves killing his power. Yet, he went through the trouble and cost of wedging his crank. I am against 1mm oversized valves for anything I build for myself, but I have gone as large as 5mm over on 3S heads for people that really want them. I believe that even in the 3S it does more harm than good. The valves are badly shrouded even when the combustion chamber is cleaned out as far as possible. The 3S with the 5mm over valves did 500+ hp on pump gas up here, but I seriously believe he would have done better with OEM size units. The most impressive valves I have seen for the DSM so far are the OEM SS replacements. They have a thinner stem and the head looks to do a good job of allowing as much air as possible to go by. I know people argue back and forth over 1mm oversized valves, but that's my opinion. They just make no sense...

HKS 272?? Awe, come on! FP comp cams, you are doing a 2.4! Take advantage! It's only $800, lol!

Good luck on your 2.4L build! It is going to be a blast! If I could do it over again, my race engine would have been a 2.4L instead of my 2.3L. I have built a lot of 2.4L units and the more I do the more I like them.

Oh, I have a 2.4L 'wide block' for sale if anyone is looking for one. I have all of the parts for it including the forged pistons and rods. The wide block fits the RWD Starquest and most M Max trucks.

Jack

[rlarsen]

I hope you are going to replace the seats to bigger units as well and are porting the area around the seats with those 1mm over valves. Just about everyone I have seen that uses 1mm oversized valves just grinde the OEM seats to match and all you are doing is just blocking more airflow with the bigger valve head. My brother did that to his head for his 4G64 and I believe that I will kick his butt this year as well with things like those valves killing his power. Yet, he went through the trouble and cost of wedging his crank. I am against 1mm oversized valves for anything I build for myself, but I have gone as large as 5mm over on 3S heads for people that really want them. I believe that even in the 3S it does more harm than good. The valves are badly shrouded even when the combustion chamber is cleaned out as far as possible. The 3S with the 5mm over valves did 500+ hp on pump gas up here, but I seriously believe he would have done better with OEM size units. The most impressive valves I have seen for the DSM so far are the OEM SS replacements. They have a thinner stem and the head looks to do a good job of allowing as much air as possible to go by. I know people argue back and forth over 1mm oversized valves, but that's my opinion. They just make no sense...
I'm going to respectfully disagree with you somewhat here, Jack. If someone's already in need of a valve job, especially on a 2.4 where the valves can be unshrouded to a much greater degree than with an 2.0L bore motor, why not do 1mm over valves? I disagree that you need to completely replace the seats. How is an oversized seat any different than a stock seat properly bored, radius cut, and blended into the runner?

Have you actually run back to back runs with a stock size valve head, and an oversized to see if you're actually losing power with bigger valves?

I do agree with you that oversizing valves is of minimal importance in these heads, which is why I don't usually recommend the extra work involved with going larger than 1mm over. Just trying to follow your thought process on this one.

HKS 272?? Awe, come on! FP comp cams, you are doing a 2.4! Take advantage! It's only $800, lol!
:confused: FP cams are ~$430 a set, not $800...unless you're counting the necessity of using high-rate springs with their more agressive grinds.

Good luck on your 2.4L build! It is going to be a blast! If I could do it over again, my race engine would have been a 2.4L instead of my 2.3L. I have built a lot of 2.4L units and the more I do the more I like them.
I will definitely agree with you here, I love the 2.4's (especially with long rods). Once you find a good crank and take measures to make sure it doesn't beat the main bearings to hell, they're awesome motors. It's the only thing I'll build for my car, if I ever get around to it.

Oh, I have a 2.4L 'wide block' for sale if anyone is looking for one. I have all of the parts for it including the forged pistons and rods. The wide block fits the RWD Starquest and most M Max trucks.
Is that the block with the larger tranny mounting pattern? What the hell were you doing building up one of those? :p

[Wazzelby]

I hate to admit it, but I think my new 2.3 stroker has crankwalk.....
The symptoms:

rpm drop of about 400-600 rpm's when I push in the clutch
car wants to die on hot days when i push in the clutch
the last couple of days I have been getting eratic pedal feel in the clutch, sometimes it feels stiff, sometimes it drops halfway to the floor. This can happen when I'm driving in a straight line down the road, not under a hard left turn (as I've read).
Plus the car just seems to have alot of vibration under accelleration, especially in first gear. I have heard that this is normal by some others that have a 2.3, others say not so much.

I have not seen any metal flakes in the oil. I do see dark black oil though after only about 1 week of an oil change. Plus the oil doesn't look consistent, it is mostly black, but some of it still looks new on the dipstick, almost like they are not mixing... if that makes sense?
Anyone have any ideas of what to check? Could it be a throw out bearing? Could it just be air in the clutch line? Please don't tell me it's crankwalk, please......

[XakEp]

If youre really worried about it, check your crank end play. I thought I had that problem and it was bad master/slave cylinders.

[JackM]

I'm going to respectfully disagree with you somewhat here, Jack. If someone's already in need of a valve job, especially on a 2.4 where the valves can be unshrouded to a much greater degree than with an 2.0L bore motor, why not do 1mm over valves? I disagree that you need to completely replace the seats. How is an oversized seat any different than a stock seat properly bored, radius cut, and blended into the runner?

Yeah, you are doing it right, but most people just stick 1mm oversized valves in there without doing anything and it's a waste. They tell me to install them and not want a port job to match. People don't seem to understand that you can't just slap those in there. You think most people spend the time to bore out the seat and runners to match the oversized valves? I had a set of heads here for a 3S that had oversized valves. The $4000 set didn't have any mods done to the seats. I didn't build them, but if I did, I wouldn't have stuck oversized valves in there if I wasn't going to touch the seats...

Have you actually run back to back runs with a stock size valve head, and an oversized to see if you're actually losing power with bigger valves?

Come on. I don't have the time to swap a head to find out, and I have yet to see anyone run a fair test to prove anything. Have you? To run a number on an engine, then remove the head, pop in 1mm over valves, and run it again doesn't seem worth the trouble. Most that do oversized valves though will also do other things to the car while the head is out which is what really makes the difference. The 1mm oversized valves didn't make the big difference if your head was also rebuilt with fresh parts in the process. Everyone I have seen so far with 1mm over valves are comparing results from an old head to a fresh head they put the 1mm valves in.

I do agree with you that oversizing valves is of minimal importance in these heads, which is why I don't usually recommend the extra work involved with going larger than 1mm over. Just trying to follow your thought process on this one.

Most people will not do the extra work needed to take advantage of the bigger valves. That is what makes them useless IMO. Most people are under the impression that just popping them in there is a good thing. If you do the work, then yes, I totally agree that you might see a small gain. To just stick them in there though would not do anything but hurt you IMO. That's why you unshroud them real good in the 2.4L, and clean the seat and port up the best you can. You do it right, and in many cases I try to get my customers to do it right as well, but most just don't get it.

:confused: FP cams are ~$430 a set, not $800...unless you're counting the necessity of using high-rate springs with their more agressive grinds.?

Yeah, with their dual valve spring setup they recommend it's expensive...


I will definitely agree with you here, I love the 2.4's (especially with long rods). Once you find a good crank and take measures to make sure it doesn't beat the main bearings to hell, they're awesome motors. It's the only thing I'll build for my car, if I ever get around to it..

Hmm, I don't know what you are talking about with the mains. I haven't had any issues with them. Not yet anyway...

Is that the block with the larger tranny mounting pattern? What the hell were you doing building up one of those? :p

Yes, I was going to build it for a Starion race car here, but I ended up getting a 2G DSM for a race car instead. I figured the starquest is not as popular as the DSM, so I thought I'd better stick to what my company really works on. To have something different didn't make good business sense. I really liked that Starion though... I had everything here to do the 2.4L conversion.

Jack

[rlarsen]

Yeah, you are doing it right, but most people just stick 1mm oversized valves in there without doing anything and it's a waste. They tell me to install them and not want a port job to match. People don't seem to understand that you can't just slap those in there. You think most people spend the time to bore out the seat and runners to match the oversized valves? I had a set of heads here for a 3S that had oversized valves. The $4000 set didn't have any mods done to the seats. I didn't build them, but if I did, I wouldn't have stuck oversized valves in there if I wasn't going to touch the seats...
Well, yeah, I agree 100% about this. I didn't realize there were actually people still dumb enough to put bigger valves in on stock seats. Seems pretty intuitive that that would do nothing, but alas.

Come on. I don't have the time to swap a head to find out, and I have yet to see anyone run a fair test to prove anything. Have you? To run a number on an engine, then remove the head, pop in 1mm over valves, and run it again doesn't seem worth the trouble. Most that do oversized valves though will also do other things to the car while the head is out which is what really makes the difference. The 1mm oversized valves didn't make the big difference if your head was also rebuilt with fresh parts in the process. Everyone I have seen so far with 1mm over valves are comparing results from an old head to a fresh head they put the 1mm valves in.
I didn't really mean to imply you needed to do that...I was more talking about flowbench runs. I'd be surprised if you saw more than a few CFM difference, even with properly installed 1mm overs, but I was just doubting that you would actually lose power.

Most people will not do the extra work needed to take advantage of the bigger valves. That is what makes them useless IMO. Most people are under the impression that just popping them in there is a good thing. If you do the work, then yes, I totally agree that you might see a small gain. To just stick them in there though would not do anything but hurt you IMO. That's why you unshroud them real good in the 2.4L, and clean the seat and port up the best you can. You do it right, and in many cases I try to get my customers to do it right as well, but most just don't get it.
It sounds like we're mostly on the same page, I think we were comparing apples to oranges before. I was under the assumption we were both talking about properly installed valves with bored/blended seats, and whatever unshrouding was necessary. I would wholeheartedly agree with you that anyone dumb enough to put 1mm overs in without doing anything else is going to see nothing, and could even lose power.

Yeah, with their dual valve spring setup they recommend it's expensive...
Haven't heard many complaints about the 3's and 4's on strokers though, despite the high initial cost.

Hmm, I don't know what you are talking about with the mains. I haven't had any issues with them. Not yet anyway...
I haven't personally seen many problems, but I know of several guys that were beating the hell out of the bearings as well as overheating/blueing them. This was at a fairly high HP level and a higher rev limit than most would run on a stroker. I'd rather be safe than sorry, so I jury-rig the bearings.

Ryan

[JackM]

Oh yeah. Many people don't seem to pay attention to the mains when rebuilding those. About 90% of the 7-bolt units I rebuild here need the mains line-honed. They appear to shrink when the engine is overheated or is old. They are always too small and never as round as I like them to be. Plus, there are revised torque specs for them if using the original bolts. If you use the old torque spec, you will over-tighten them making the mains even smaller. We found a .0015" difference in main size when comparing the old and rev torque. That's a surprisingly huge difference! When you pop in new bearings with a main that is too tight, well, you get a wiped out bearing. I don't think RPM has anything to do with it, unless something is happening to the oil pump at high RPM. I have a guy with an 8.5k RPM redline on a 2.4 with no issues, and a couple of 9k RPM guys with the 2.3L too without problems so far. Even on my wedged cranks, I don't see any issues... What RPM do they appear to get pissed off at? What HP numbers are we talking about here?

Unfortunately, I have seen many 'autoparts store' engines here that have mains way too tight. They hack a crank so it is too big, and hone the mains so they are too small. I had a 7-bolt we tore down the other day from Advanced (yeah, I don't know why people buy those either) and the main got so hot that layers of clevite material were peeling off, lol! That car came in with main bearing knock. Oh man, I really hate those damn autoparts store remans! They are such slime-balls that they install the warranty heat indicator on the freeze plug right next to the turbo turbine housing. So even if you never overheated the thing, the tab will change color anyway voiding any chance of a warranty repair. Every sucker I see that comes in with an autoparts store reman only has a few miles on it before they fail. They really start kicking themselves when they figure out I could have built them a 2.3L stroker for the same price, lol! Shoot, I used to never see those reman store units until a few months ago. At a 3 engine build average per week here, I see about 1 reman store unit every month now. It sucks because everything is complete junk in them. I have to find a new block and everything to do it right...

Jack


I haven't personally seen many problems, but I know of several guys that were beating the hell out of the bearings as well as overheating/blueing them. This was at a fairly high HP level and a higher rev limit than most would run on a stroker. I'd rather be safe than sorry, so I jury-rig the bearings.

Ryan

[iamtall77]

Hey, we got two great DSM guys here talking about 2.4L. Awesome! I've got a few questions though. I know there has been some debate about 7-bolt 2.4L and if they also crank walk. Is this an issue at all? What kind of cams should we run? I know FP has a set you were talking about, but what is "recomended"? I'm not looking for huge HP numbers, but what are good turbo sizes to look into? I talked to Jack about maybe a 60 trim for 500hp uncorrected at the wheels. (this is also a RWD setup. less drivetrain loss) Also what about things like water cooled turbos? Is it necesarry for a street car even if I don't push it that hard that often on the street? I'm just trying to simplify the setup a little on this one. What other areas of the engine should we look at to ensure a good build? Obviously the mains have been addressed. Any other areas that seem to cause problems?

[rlarsen]

Plus, there are revised torque specs for them if using the original bolts.

Really? This is the first I've heard of that. Where did you get them? Was there a TSB I missed? What are the revised specs? Never had a problem so far, though.

What RPM do they appear to get pissed off at? What HP numbers are we talking about here?

8,500 - 9,000 redline, probably 500HP range. Bearing shells were overheating. It's a relatively easy fix.

They hack a crank so it is too big, and hone the mains so they are too small.

How the hell are they making the crank too big? Actually welding the journals and pins then re-cutting them? That seems like a ****load of work...are they re-nitriding them? I'd assume not. Although I guess if you're only talking about 7-bolts, they aren't nitrided to begin with.


Auto parts store engine rant...

Holy crap, I can't believe someone would buy a shortblock from a parts chain. It's hard enough for an experienced builder with lots of 4G specific knowledge to build these right, let alone Johnny-hacksaw working for the parts chain for bottom dollar.

I feel pity for you for having to work on junk like that...

Ryan

[JackM]

Really? This is the first I've heard of that. Where did you get them? Was there a TSB I missed? What are the revised specs? Never had a problem so far, though.

Yes, there is a TSB for the OEM bolts. If you are building race engines though with ARPs, then there is nothing that I have seen for those. The 7-bolt torque in old manuals are 25nm and a 90 turn. They have changed it to an actual torque number like the 1Gs.

8,500 - 9,000 redline, probably 500HP range. Bearing shells were overheating. It's a relatively easy fix.

Hmm, I haven't seen anything with that yet...

How the hell are they making the crank too big? Actually welding the journals and pins then re-cutting them? That seems like a ****load of work...are they re-nitriding them? I'd assume not. Although I guess if you're only talking about 7-bolts, they aren't nitrided to begin with.

They will grind the crank .010", but they keep it on the big side. It's like they really grind it .008-9". Every autoparts store crank goes straight to the garbage.

Holy crap, I can't believe someone would buy a shortblock from a parts chain. It's hard enough for an experienced builder with lots of 4G specific knowledge to build these right, let alone Johnny-hacksaw working for the parts chain for bottom dollar.

I feel pity for you for having to work on junk like that...

Ryan

As many as I've seen lately, you are sure to run into one soon, lol! Oh, you will love it!

Jack

[JackM]

I have seen 2.4L rebuilt engines walk. So I would say yes, it can happen. The 2.4Ls though are not crankwalkers like some of the low mileage 2.0L turbo units. The ONLY reason for a 2.4L to walk is if the mains are too tight, IMO. If they are too tight, you will squeeze the main until no oil will leak out of the side anymore, which is where the thrust gets its oil. The mains share the same oil galley, duh, but if one is tighter than the others (usually center main) then the oil will go to the bearings with the most clearance and leave the center main and thrust dry and to burn up/walk. I always machine the center main crank journal .001" smaller than the rest to be sure the thrust gets plenty of oil and the clearance is there.

IMO, go through the trouble of using a water cooled housing. I have seen many non-water cooled units survive a long time, but the water cooled one always seem to have twice the life. I am really worried about my T04RHO in my car because it's not water cooled. I am getting enough power now where I think it's burning the oil in the unit pretty good on extended WOT runs. Like the other night on a 30-130 roll against a 10 second bike :) Got him by 6 lengths by 130. Oh yeah, lol! I wish the turbo was water cooled. I think its days are numbered... 60 trim water cooled would be nice. Get a big turbine though. Like maybe a p-trim .82A/R. I have a p-trim T3 .82A/R on mine and I like it, but will probably go T4 turbine soon. It's laggy, but on a small 60 trim compressor, it might be just right...

The only other thing I can think of is make sure the cam timing is perfect. You will probably need cam gears for that. Also, install the head without the cams in it and torque it down to the block. Rotate the crank with all of the valves closed to be sure the pistons don't hit them. Yeah, its really weird, but I had an engine that was machined by a customer once and not myself. They shaved so much off the head and deck, that the valves, even when closed, would hit the pistons. So just check the pistons and deck real close before you assemble, and also check again by rotating the crank with no cams just to be 100% sure. Rotating with no cams, just so you know, will not bend valves, because none will be open. I'm sure there are other things to check, but I'm too tired to think of anything else right now.

Jack

Hey, we got two great DSM guys here talking about 2.4L. Awesome! I've got a few questions though. I know there has been some debate about 7-bolt 2.4L and if they also crank walk. Is this an issue at all? What kind of cams should we run? I know FP has a set you were talking about, but what is "recomended"? I'm not looking for huge HP numbers, but what are good turbo sizes to look into? I talked to Jack about maybe a 60 trim for 500hp uncorrected at the wheels. (this is also a RWD setup. less drivetrain loss) Also what about things like water cooled turbos? Is it necesarry for a street car even if I don't push it that hard that often on the street? I'm just trying to simplify the setup a little on this one. What other areas of the engine should we look at to ensure a good build? Obviously the mains have been addressed. Any other areas that seem to cause problems?

[XakEp]

Yeah, its really weird, but I had an engine that was machined by a customer once and not myself. They shaved so much off the head and deck, that the valves, even when closed, would hit the pistons. So just check the pistons and deck real close before you assemble, and also check again by rotating the crank with no cams just to be 100% sure.

I was so pissed at that machine shop for that. Ugh. At least it got me to go with a 1G head.

[ErikW]

...with a 1g...

When my first, freshly rebuilt head took a dump because of bad machining and assembly of the guides, I had to redo it. Since I had been able to salvage 14 of my 16 1mm over valves, I decided to redo the head the same way. I was out of money. I was the one that took it in the shorts for this crummy work on both the head AND block. So I didn't do the total port job on the head. I wish I could have.

I would recommend porting the head and doing what's necessary to make the best out of the 1mm over valves. It would be a 'better for the effort' and 'while your in there', kind of thing. imho.

Although, with my larger turbo and raised compression, I never noticed a large turbo lag or reduction in top end power. (18g vs. T3/4// stock compression vs. 9:1) So the results were quite the opposite. The top end is noticeably better and the mid range is better as well. This resulted in hi trap speeds with, not as impressive, qtr mi. times by comparison.

It seems that most of us are looking for pretty much the same power results/improvements, since driving the car on the road is Job-One.

I think if I had to do it over and had the money, I'd do a total port, bowl, and polish to the head. But then I would also do higher lift cams, cam gears and dual springs, along with a larger BB turbo, as well. And, I'm probably missing something else here... But, you see? This is a domino effect. I'm pretty happy with my setup even though the car is not tuned worth a Cr@p now.

As for the block. If I had known that this was an alternative for a better low/mid power range setup back then, I would have seriously considered the 2.3 or 2.4 as well.

When I had my 1g head taken over to Jack, whoever he has doing the headwork is amazing and pays close attention to detail. I'd recommend him!

[D Walker]

The one thing I will add is that with larger turbos you dont need to worry as much with water cooled housings. The larger castings of the turbine housings handle the heat much better and they typically run a little cooler anyway. On smaller- 50trim and smaller or any mitsu based turbo I definitely think you need watercooled housings on the smaller turbos to keep them alive.

[JackM]

whoever he has doing the headwork is amazing and pays close attention to detail. I'd recommend him!

Hey, thanks! I used to do them myself. I'm not sure if yours was one I did or not. It just took too much time for me to rebuild them, so I have a friend of mine do it now. This guy has some serious patients! Most shops press out the old guides. He drills out the old guides until they fall out on their own. This prevents damage to the head and makes for a clean and straight area for the new guide, and the valve to seat alignment is a lot closer too. You don't have to grind you valves and seats as much. For him to drill out each guide like that is very time consuming and is a lost art for these heads... Another common thing shops do is bead blast the head. It's okay to do on the outside, but many are doing it on the inside now as well which damages the head. The guy that does my head work is over 60 years old and has experience with race cars that I will probably never have. He is truly gifted in his work and I hope he will continue to use me as his play money/extra income for many years to come. Guys like him just don't seem to exist anymore. He is also the guy with the cool mill I use to machine my 4 spider centers and double synchro gears. If it wasn't for him, I wouldn't have figured out how to double synchro factory OEM gears with his equipment.

I know many are going to disagree here, but my opinion about porting is not to do it. I used to think it was a good thing to do, but not anymore. Without a flowbench, you are just guessing and probably doing more harm than good. Plus, I would put my car up, with my stock head, against anyone here with a ported unit. I would be more than happy to hand you your ass. I hear you are doing pretty well yourself Erik :) I think the money and time is better spent on other things that will do more. I am convinced with my car that porting is not needed. ...yes Tyler, you were right, I was wrong...

Don, I would agree that bigger turbos have less backpressure, so you would have less heat while it's running, but I think a lot of heat is also dissipated with water cooled units when the car is shut off too. The coolant keeps more heat away from the bearing housing to prevent cocking when the oil circulation stops. I think that is a problem for even large turbos. On my car though, even with the big turbo, I know that sucker is getting super hot.

Jack

[Mirage]

I would have to disagree on the portwork thing.

Last season, I had a bone stock cyl head with some very minor "polishing" done to it. I also had the FP 3575 turbo installed with that particular setup. If I rolled onto the throttle in a higher gear, the turbo would surge badly enough to where I would have to let off and get back into it again.

Fast forward to this season. The only changes that I did to the setup was a ported cylinder head and a fresh rebuild on my engine (engine had no changes to it that would increase airflow through it)

Now when I roll onto the throttle even at lower rpm than last season, it doesn't surge at all and it pulls smoothly and harder up to it's 8,500 rpm rev limit. Airflow numbers are up too. I'll have to go back to my logs to see how much more they were up though.

This portwork was work that I had done on my own with only a diegrinder bit, graduated cylinder, set of dial calipers and a pair of intake and exh mani gaskets.

Granted this doesn't have any real dyno numbers or quantitative facts, it still showed me a great improvement over the stock head.

Obviously, Your milage will vary

Marcus

[Outlaw]

I would have to disagree on the portwork thing.

Last season, I had a bone stock cyl head with some very minor "polishing" done to it. I also had the FP 3575 turbo installed with that particular setup. If I rolled onto the throttle in a higher gear, the turbo would surge badly enough to where I would have to let off and get back into it again.

Fast forward to this season. The only changes that I did to the setup was a ported cylinder head and a fresh rebuild on my engine (engine had no changes to it that would increase airflow through it)

Now when I roll onto the throttle even at lower rpm than last season, it doesn't surge at all and it pulls smoothly and harder up to it's 8,500 rpm rev limit. Airflow numbers are up too. I'll have to go back to my logs to see how much more they were up though.

This portwork was work that I had done on my own with only a diegrinder bit, graduated cylinder, set of dial calipers and a pair of intake and exh mani gaskets.

Granted this doesn't have any real dyno numbers or quantitative facts, it still showed me a great improvement over the stock head.

Obviously, Your milage will vary

Marcus


Who ported your head? Did they have a flowbench? What were the before and after numbers? How much did you spend on the porting?

[D Walker]

Afraid I dont find anything conclusive in your results Marcus.Simply rebuilding a tired engine will increase airflow through it. Your surging could have just as easily been caused by the turbo overspeeding due to boost leaks, a poorly ported WG housing, bad boost control-intake leaks will contribute to this-improperly sized TB, etc. I recently dynoed a badly surging- same symptoms as your car- Supra and finally tracked the cause to a badly ported manifold which is causing issues in the WG.
I also believe Jack is running a significantly larger turbo than you are(t3/t4R) and is still on the stock head and stock 1G intake manifold with no surge issues. I could be wrong about that though, but I am sure he will chime in. Its not valid to comment on my car, because I have a mildly ported head, 3" tb, and SMIM, but even when I had the stock 1G IM and head on the small t3 I never had any kind of surging issues.

[dsm_gsx97]

Who ported your head? Did they have a flowbench? What were the before and after numbers? How much did you spend on the porting?

Go re-read his post...he answers that question in his last 3 paragraphs. :D


This portwork was work that I had done on my own with only a diegrinder bit, graduated cylinder, set of dial calipers and a pair of intake and exh mani gaskets.

Granted this doesn't have any real dyno numbers or quantitative facts, it still showed me a great improvement over the stock head.

Obviously, Your milage will vary

Marcus

[Mirage]

The reason I did a rebuild was not because of leakdown or compression results. It was because I had a ticking noise that I could not find for the life of me from the bottom end. Finally turned out that it was a slightly cracked wristpin that hadn't migrated or done much damage yet.

Flowbench? It's great for checking static flow, not dynamic. Flowbenches don't take resonance and the engines breathing characteristics throughout the rev range into account.

All the ports were shaped as close to each other as I could and they were the same volume to each other with a 1/2 CC tolerance. I took my time porting and shaping this sucker.

Don, I wasn't saying you'd find anything conclusive. All I was merely saying was that there was a significant airflow difference through the engine. Take it for what you will...

Marcus

[Kibo]

I also believe Jack is running a significantly larger turbo than you are(t3/t4R)

Define 'larger'? Does the compressor flow more than an FP3575 (75 lb/min)? Or are you comparing the T3 hot side to the GT37 wheel on the FP3575?

Marcus, I'd love to see some airflow numbers if you could dig them up. I'm interested in the before/after comparison (as opposed to absolute numbers).

[D Walker]

I believe the t04R does flow more than 75lb/min but I dont have the specs offhand. I also am not sure which version Jack has on that car, and I am not sure how much he wants shared on a public forum-if he wants he can comment.

[yokotabrat]

From what I can tell from here (http://www.full-race.com/catalog/product_info.php?cPath=214_162&products_id=64), the T04R is generally referred to as a T67 compressor wheel in a T04S cover which flows 75 lbs/min, same as the FP3575. Either way, both turbos have the capability to produce some serious numbers.

[JackM]

Yep, that's what I have. Mine though is an HO model. The only thing I can see to make it 'high output' is it looks like the compressor wheel is knife edged and has some changes done to it. It doesn't look like a standard T04R wheel, but it does have to T04S housing. I am also using a true garrett turbine assy with a large manifold and downpipe that I made. I think mine and the FP are pretty much the same darn thing...

Jack

[Mirage]

Other than the FP turbine housing, I thing these two turbos are twins.

My 3575 has the knife edged compressor wheel as well. It would be interesting to see which turbo prevails ;) .

I still need to calibrate my MAFT to get accurate airflow numbers because according to DSMLink, I'm still around 48 lb/min. A little far off I would guess. Otherwise, I'd just ask what kind of airflow numbers you're getting.

Marcus

[JackM]

Yep, you're right. My brother corrected me today on that also. The compressors are the same, but our turbine housings are a little different. You have the nice SS unit and I have the cheap Garrett T3.

On race gas we were at 32PSI of boost and got 72lb/min on Tylers street tune in 3rd gear. Tyler and my brother were tuning it on a new long straight stretch of road on Powers on a nice cool night. I will see if I can get the log. I don't know if we used my brothers computer on that log or mine though... I will also let you know what I have the MAFT set to as well. My brother and I are going to do more tuning on Monday or Tuesday on pump gas, so I will make sure I save those logs as well if you want to see them...

Honestly, I am surprised my turbo still works. It's not water cooled and I have been backfiring and overheating the piss out of it these past couple of weeks. I believe the two of us have very similar cars :) Same turbo, same 2.3L... Once you get yours running how you like it, we should meet sometime and set up a friendly race against each other :) I'm always up for some friendly wagering also, lol!

I heard you are now on 100% E85. I have been in the process of doing the same to mine. How do you like it so far? I have upgraded everything but my injectors. Are the 1600s doing okay?? Are they too big, small? Thanks!

Jack

[Mirage]

I *love* E85.

I'm still somewhat untuned, but so far I'm at 40 psi with 17 degrees of timing. *No* knock. I love alcohol. In all senses of the word :) .

It does seem to make the car run smoother and feels a little more "peppy" down low. The 1600's are being run right around 77% duty cycle if I remember right. For this size turbo, I would say that the 1600's are a good match for E85. For gasoline, 950-1000cc injectors are a good match. Close to being maxed, but still usable.

Right now, I need to pull the tranny as the clutch lets go right around 6200 at anything higher than 35. Guess a 2900 and a 6-puck aren't enough. Twin disk time!!!

I will be dropping the tranny tomorrow in hopes of getting this thinggrabbing again.

Marcus

[JackM]

That's awesome with the E85! Sucks to hear about the clutch though, I have the same thing. It is not slipping yet, because it's still new I think, but it probably will soon if yours is. Funny we have the same clutch too, lol! Are you going to be using the same twin disk setup as 97TurboTalon? I believe it uses twin ceramic disks, not carbon and is a Quarter Master 7.25. It's supposed to be pretty economically priced if I remember correctly... If so, I might order one with you as I feel my ACT is also a ticking time bomb. Maybe we could get a discount on 2 orders? I might find a 3rd person if that would help even more on prices for the two of us. That's if you want to go that route I guess though. Thanks for the info!

Jack