Stripped Input shaft

[steve]

Well im getting really tired of working on this car
When I first put the XTD Stage 4 clutch(6 puck unsprung) in it wasn't making any noises at idle and lately after about ~1000k on it, it starts to make a knocking sound at idle. I really thought this was normal and just clutch chatter. Then last night I let my friend try to drive it and he kept stalling it. So right after that i'm at a light and i take off in first, then go to shift into second, release the clutch and it's like i'm in neutral. Its making a nasty noise when the clutch is released,the car will not move but I can shift into every gear perfectly, and I do not have any broken cv axles. Whats crazy is I have not launched it yet. My question is, has this happened to anyone else with a six puck?

[matthewdesigns]

I have not had my clutch out in the last year, but may soon. It's a 4 puck unsprung ACT. Have you pulled it apart to verify that the shaft is stripped?

If it is, I think it's got less to do with the fact that it's 6puck, but that it's a solid hub disc. There are no springs in the disc to absorb driveline lash, so everything else in the system is going to be more highly stressed than with a sprung hub disc. Every other component is going to be subject to more vibration and will wear more quickly. How did the shaft splines look when you installed the clutch? They may have been somewhat worn and the clutch wiped them out altogether if that proves to be the case.

[steve]

No I have not pulled it apart yet but Im pretty sure the input shaft is striped or maybe the hub on the disk broke. When it happened there weren't any abnormal sounds but il post some picks when I get it apart.

[steve]

When I was taking the transfer case off today found some of the rivets lol so I was happy that the input shaft was ok. When I took the tranny out the hub was completely separated from the disk. Luckily it didn't mess the flywheel or pp. What I noticed is the act unsprung 6 puck has 2x the rivets holding the hub to the disk and when I put the broken off hub on the input shaft there is some play is when I turn it back and forth? Is that normal?
http://i908.photobucket.com/albums/ac290/stevetalon/MOT00001.jpg

[matthewdesigns]

Glad to see it's the disc, but not really that glad it broke lol. This is only after about 1K miles? How much have you launched the car? I guess it's obvious why ACT has 2x the rivets.

You will have some play between the shaft and hub based on how much wear the input shaft has. Unless it's brand new, there could be up to about 1-1.5mm worn off the side of the splines before they become too weak and completely shear under load depending on how much torque you make. If you start with a worn shaft, then that's only going to increase the rate of wear on the hub and shaft as there's a gap that can collect dust from the disc, which will act as an abrasive between the surfaces.

Sucks that this broke so badly. Is it under warranty? Would you even trust another one? How much power are you making for the sake of posterity, and what it takes to break one of these?

[steve]

No didn't launch the car at all with this clutch. Power wise I'm thinking over 500hp at the crank and I have no idea what torque lol when I was running 32 psi. Thats probably why it broke I remember it wasn't shifting so good when i was at 32psi. Yeah its got a 12 month warranty:D I told the guy I wanted a refund for just the disk so I could buy an act 6 puck unsprung but he told me he would ship another disk to me right away thats alot stronger and it wont break again. We'll see though. Cant beat that for a 180$ clutch.

[Cloud]

Not going to lie that sucks. I am a strong believer in sprung hubs, especially in a car that has no other driveline dampers (some cars have them on the driveshaft/differential for instance). And really, for a street car I hate puck clutches as well ;)

[steve]

Yeah pucks aren't to fun to drive around as a dd

[steve]

I was going to get a sprung 6 puck instead, but I always hear that people have those springs popping out and doing damage. Maybe it does happen as often as I thought. I just would hate to take the tranny off again for a spring popping out

[matthewdesigns]

I'd stay away from the sprung hub version...one more thing to go wrong. Good luck with the new disc, I hope it holds together better for you. Post a pic of it when you get it if you can.

[steve]

I'd stay away from the sprung hub version...one more thing to go wrong. Good luck with the new disc, I hope it holds together better for you. Post a pic of it when you get it if you can.

Thanks, I hope it holds up too. I'll make sure I post some pics.

[Dane Becher]

I was going to get a sprung 6 puck instead, but I always hear that people have those springs popping out and doing damage. Maybe it does happen as often as I thought. I just would hate to take the tranny off again for a spring popping out

Happens with an organic sprung disc too :mad:

[Cloud]

The new sprung versions of the ACT clutches are much beefier. I had a spring fall out after about 20k miles with my original 2600 and street disc. The revised version I got with my 2900 had much thicker springs in it and I'm not sure people are having quite as many problems with them now. Actually the 2900 was a better clutch in just about every possible way.