I don't know about you guys, but the stock clutch on my new 2008 Z06 is too light & has a non-linear feel. I was thinking about removing the helper spring on the clutch pedal, but heard a rumor that GM issued a tech bulletin advising dealer mechanics to look for this mod on vehicles with clutch/trans damage and to deny warranty claims if this mod was done.
Anyone know if the GM bulletin rumor is true? Why/how the heck would this mod result in clutch/trans damage? It's a fairly common mod for some other cars that helps solve the non-linear clutch feel, as all the spring usually does is reduce effort over center. I don't see how it would damage anything from it's removal (unless you were too weak to press the clutch in fully after removing it or riding the pedal), but I don't want to do it if it's gonna void my warranty!
Let me quote a knowledgeable source on another forum:
"THIS COULD CAUSE FAILURE OF THE HYDRAULIC SYSTEM.
This system, if not allowed to return all the way, can cause syncronizer damage, incomplete clutch release and increased clutch wear of the friction surfaced disc."
Let me quote a knowledgeable source on another forum:
"THIS COULD CAUSE FAILURE OF THE HYDRAULIC SYSTEM.
This system, if not allowed to return all the way, can cause syncronizer damage, incomplete clutch release and increased clutch wear of the friction surfaced disc."
I'd leave well enough alone!
Hmm, interesting... I can see how (if the clutch pedal didn't rise/release fully) it could cause some of the damage indicated above, but it also sounds like the guy from the other forum is stating damage will be caused at both ends of pedal travel (clutch engagement & release). I'm still curious about how removing the pedal helper spring would cause this, unless the pressure plate & hydraulics do not have enough force to support the weight of the clutch pedal riding against the master cylinder actuator without having the spring to help keep the pedal "full up". I guess the spring transition from helping to press the pedal in, to helping hold it up when the clutch is fully released is mandatory in our cars?
Somewhat strange clutch design if the spring is required to hold the clutch pedal up in our cars... never had that before.
the pedal has that spring to help overcome the pressure needed to exert the force you need to disengage the clutch (push the pressure plate to disengage)... It is there for help... I'm not really sure that the removal of that spring would make it seem more "linear" or not... Its there for comfort, and help overcoming the force needed... if you want a stiffer feel, upgrade to a better clutch..
I had a spec stage III on my last car, and the thing chattered for a while when it was new, and the length needed to engage and disengage was minimal... It was different... but didn't make the car anymore fun to drive IMO
the pedal has that spring to help overcome the pressure needed to exert the force you need to disengage the clutch (push the pressure plate to disengage)... It is there for help... I'm not really sure that the removal of that spring would make it seem more "linear" or not... Its there for comfort, and help overcoming the force needed... if you want a stiffer feel, upgrade to a better clutch..
I had a spec stage III on my last car, and the thing chattered for a while when it was new, and the length needed to engage and disengage was minimal... It was different... but didn't make the car anymore fun to drive IMO
That's what I understood the spring to do, same as on all the other manual trans cars I've ever owned. This was just the first time EVER that I heard anyone say it could cause any damage! That just doesn't make any sense at all unless people just aren't pressing the pedal in fully after they take it out, or there's something seriously weird about our clutch setup in these things.
Don't think I need a new clutch on my stock 600 mile Z06 just to improve feel! I'm just used to the clutch feel of my M3's and other cars, which are more linear & predictable than in my Z06. And being an engineer, I haven't heard one good explanation of why this can cause damage & am curious if anyone knows a "real" reason.
BTW, before I bought my Z06, I drove a buddy's at the track... he pulled out his helper spring as he wasn't fond of the extremely light clutch feel either. Guess what? The feel became much more linear throughout the range of pedal travel. If I hop from my car into his, his clutch feels much more linear & predictable than my stock setup, which starts off light, goes to high force in the middle then gets light again towards the bottom of pedal travel. His just starts out medium, and grows to a nice level of force within the first inch of pedal travel & stays linear after that. Sure there's more force required, but it's also a more predictable feel.
I don't know how it could damage the clutch either... maybe its also there to make the engaging softer... who knows...
I'm a M.E., and unless I am overlooking something, it seems like this wouldn't cause trouble with the clutch/pedal unless you keep partial pressure on it so the clutch slips or something... who knows
From what I understand the spring works two ways, it keeps the pedal extended so it doesn't "ride the clutch" then goes overcenter and makes the pedal easier to push in. It's the first part that could cause problems if removed.
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its called "hold down assist spring" helps in traffic.ive 30 k on my 07 z i found the spring on the floor 1k ago broke.i did feel a diff. but to be honest i cant say good or bad,my clutch took about 1/2 k to smooth out.i change the fluid when i do oil changes.ive no beefs with the clutch and i drag the car and speed shift.so pull it ,if warentee comes up act dumb but i see no issues
One of our local tuners is suggesting that we replace the C6Z spring with a C5 spring to provide a more linear feel on clutch release. I'm going to visit him shortly and try it out.
its called "hold down assist spring" helps in traffic.ive 30 k on my 07 z i found the spring on the floor 1k ago broke.i did feel a diff. but to be honest i cant say good or bad,my clutch took about 1/2 k to smooth out.i change the fluid when i do oil changes.ive no beefs with the clutch and i drag the car and speed shift.so pull it ,if warentee comes up act dumb but i see no issues
Since your spring broke and is no longer in there, can you verify if the clutch pedal sags at all or if it still seems to be at full height? If it still sits at full height even without the spring, that should mean that it's fine. If it actually needed the spring to "keep the pedal up" to avoid applying any unintentional pressure on the hydraulic clutch, it would seem you would be able to easily tell just by looking at pedal height before & after.
It could be any folks that had damage after removing it had a bad habit of letting their foot slightly drag on the clutch pedal while driving, and having the spring in there added just enough force to keep them from slipping the clutch. And/or they didn't press the cluch in far enough to shift after taking it out & ground gears.
One of our local tuners is suggesting that we replace the C6Z spring with a C5 spring to provide a more linear feel on clutch release. I'm going to visit him shortly and try it out.
That seems like the best option! If the C5 spring is lower force & works, then great. Keep us posted on your results & a P/N.
Since your spring broke and is no longer in there, can you verify if the clutch pedal sags at all or if it still seems to be at full height? If it still sits at full height even without the spring, that should mean that it's fine. If it actually needed the spring to "keep the pedal up" to avoid applying any unintentional pressure on the hydraulic clutch, it would seem you would be able to easily tell just by looking at pedal height before & after.
It could be any folks that had damage after removing it had a bad habit of letting their foot slightly drag on the clutch pedal while driving, and having the spring in there added just enough force to keep them from slipping the clutch. And/or they didn't press the cluch in far enough to shift after taking it out & ground gears.
no diff in pedal height.the throwout bearing is ALWAYS in contact with the psi plate fingers this why it self adjusts.there is slight play between pedal pushrod and master cyl.much ado about nada.the factory manual also states when replacing to FINESSE the spring in place [AKA its a pain in the butt] this aint rocket science if it breaks so what it wont hurt anything.its a corvette not a beemer so it feels like a corvette clutch.change your clutch fluid every oil change with racing brake fluid and dont slip it and it will last you 100 k
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