Clutch!

[Bizzy]

Again, this is my PERSONAL OPINION! That's the great thing about it, everyone has a different opinion...

Personal opinions are great things, we each speak from our own points of view and experiences. Though I still think one of the problems you had with your disk was the fact that it was a reman'd unit and it was defective. I don't have many worries with mine since it's brands new.

 

[twr]

I don't think the straps have anything to do with PP clamping pressure, that's determined by the fingers/spring. The straps are reinforced to help with the shock load during a launch or shift.

This is correct, the diaphram spring delivers all the clamping. Actually to many or to strong of straps will reduce clamp load. The IPT pressure plate I have has had the pivot points moved inward (IIRC) to increase clamping. We'll see how much power it can take before to long.....

 

[91taurisho]

Let me re-phrase my statement cause it came out wrong. What I really meant was the same thing that SHOAZ said. Shock load is determined by the PP straps and without HD straps the shock the disc endures is much greater, IMO. Wether you agree with me or not, I still feel it was a combination of the PP AND the disc. Wether you want to believe me or not, I FEEL that it was A bad PP and disc. Let me reitterate, I will never recommend getting a stock clutch kit unless you never abuse your car, in any way shape or form. This seems like it has become a ******* match and this will be my last post in this thread about my PERSONAL FEELINGS TOWARDS STOCK CLUTCHES unless it's really necessary. The reason I say this is because you seem like you're attacking my opinion. The end.

 

[revhardSHO]

Let me re-phrase my statement cause it came out wrong. What I really meant was the same thing that SHOAZ said. Shock load is determined by the PP straps and without HD straps the shock the disc endures is much greater, IMO. Wether you agree with me or not, I still feel it was a combination of the PP AND the disc. Wether you want to believe me or not, I FEEL that it was A bad PP and disc. Let me reitterate, I will never recommend getting a stock clutch kit unless you never abuse your car, in any way shape or form. This seems like it has become a ******* match and this will be my last post in this thread about my PERSONAL FEELINGS TOWARDS STOCK CLUTCHES unless it's really necessary. The reason I say this is because you seem like you're attacking my opinion. The end.

Okay John Kerry!!! j/k

If you really think the stock clutch is that bad, by all means you should defend your position. Im sorry if I disagree, I just dont see the light. Oh well, sorry to highjack the thread SHOTIME! Good luck with finding a replacement clutch!

 

[twr]

I tend to agree with Scott on this issue of not using a stock clutch if you are ******* the car. The thought of a strap spinning around slicing and dicing the transmission until it cut into a wet area doesn't sit to well with me. I would rather invest my money in a clutch that at the bear minimun has heavy duty rivets or aircraft quality bolts (like Gary's design or Southbends... who got the idea from Gary) For those SHO's that are mildly driven daily drivers, the stock unit is good enough.

 

[revhardSHO]

I tend to agree with Scott on this issue of not using a stock clutch if you are ******* the car. The thought of a strap spinning around slicing and dicing the transmission until it cut into a wet area doesn't sit to well with me. I would rather invest my money in a clutch that at the bear minimun has heavy duty rivets or aircraft quality bolts (like Gary's design or Southbends... who got the idea from Gary) For those SHO's that are mildly driven daily drivers, the stock unit is good enough.

I agree with that. Can the stock rivets be drilled out and stronger bolts used? I have a good PP around here somewhere, and that would at least give me a little more security with the 9 pucked metallic disk Im going to be using. Do you know the specs on the bolts?

 

[gmorrell]

This is correct, the diaphram spring delivers all the clamping. Actually too many or too strong of straps will reduce clamp load. The IPT pressure plate I have has had the pivot points moved inward (IIRC) to increase clamping. We'll see how much power it can take before too long.....

The drive straps between the pressure plate and cover do very little to reduce the PP clamp load. You can clamp one end of a stack of straps in a vise and still easily move the other end with your hand. You'd need to have one **** of a thick stack of drive straps to fight the PP clamp load, and there's no point in doing this because three stacks of 3 or 4 straps each has plenty of tensile strength for even the highest HP blower SHO.

Properly sized and installed, the drive straps actually provide a light lifting force to the pressure plate when the clutch is released. This makes the clutch release a little quicker from the friction material, but the lifting force is only a few pounds compared to the diaphragm clamp force of near 1800 pounds in a stock SHO clutch.

OEM SHO clutches frequently fail due to shearing the drive strap rivets. The rivets are fairly soft and will shear if the clutch sees heavy shock loading, either driver-induced, or from an aggressive friction lining. This is why I and others replace the rivets with high grade bolts or larger rivets. When I was building SHO clutches, I replaced the rivets with 160,000 psi tensile NAS close tolerance airframe bolts.

The other strap failure mode is when some numbnutz downshifts too aggressively and/or doesn't match revs on a downshift. This sends a boat load of reverse torque through the clutch, which puts the drive straps in compression, causing them to spread or bend. The result here is that the pressure plate is driven off-center in the cover and the clutch balance is lost. If the clutch goes out of balance, it will ususally cause the engine to shake at idle. You can also knock a PP off-center by dropping the clutch cover on the floor.

 

[revhardSHO]

Where can I get these aircraft bolts? Is it as simple as drilling out the rivet and torqueing the new bolts down?

 

[91taurisho]

Okay John Kerry!!! j/k

If you really think the stock clutch is that bad, by all means you should defend your position. Im sorry if I disagree, I just dont see the light. Oh well, sorry to highjack the thread SHOTIME! Good luck with finding a replacement clutch!

I don't like Kerry... But that's not for this forum
I'm glad you stand by your position. I'll stand by mine as well