ImBatman

Thought you guys might be interested in this response from Centerforce. The family and I are on vacation in Myrtle Beach this week so I have not had a chance to work on it. The trannie is out but I did not get the BH off to look at the PP and the flywheel. I went ahead and sent my problem description to Centerforce and here is what they said.

"The clutch will operate properly without the centrifugal weight system. The weight system is designed to provide additional clamp load with the increase of the engines rpm's. If this problem persist with the vehicle in motion or free revving of the engine and there are no tuning issues, I would speculate a out of balance condition also. I don't know if the balance of the pressure plate was check with the rotating engine assembly of if the the balance was tampered with after leaving the manufacturer, which this could cause the vibration if the weight were not fasten down while checking the balance or if the proper pressure plate bolts are being used to fasten the pressure plate to the flywheel. If you were going to remove the weight, I would suggest checking the balance of the pressure as a process of elimination to find the cause of the vibration. The weight system has not been changed for this clutch is the last several years. If you need us to check the balance, feel free to contact us at (928) 771-8422"



Wade

ImBatman

Here is some additional info from centerforce after a follow up email I sent. They have been very helpful and quick to respond. For those who have not followed the thread on the problems I have been having. In short I have a bad vibration from 3-4k rpms. So far I have eliminated everything from the tranie back and everything hanging on the front of the motor. The culprit is either the flywheel and\PP.


From centerforce
"If that is all the was done and you developed a vibration, it's possibly the that the pressure plate was rotated on the flywheel which could cause a slight vibration if the two worst case scenarios happened to be aligned, meaning the heaviest part of the flywheel aligned with the heaviest part of the pressure plate. We've experienced by simply by rotating the pressure plate a 180 degrees on the flywheel, thus could effect/change the balance. It's possible that if you rotated the pressure plate on the flywheel, thus could also cure your vibration."

Gordonm

Interesting. I thought all the pressure plates were nuetral balanced and it did not matter how they are indexed on the flywheel. Unless you balance it all as an assembly and mark the flywheel and PP so they index together it would be off. How many thousands of PP are just put on the car without this being a problem. I guess they don't expect them to be revved to 6500 rpm. Keep us posted when you get back. Enjoy your time off.

pws69

I think the point that they are trying to make is valid: everything has a tolerance and in rotating masses, tolerances can add up and create an imbalance. I think their suggestion has merit and is worth a try.

gve

I had a vibration between 3-4000 rpm in my 454 that was rebuilt and balanced 3 years ago. I tried everything to get rid of it the shifter would rattle at those rpms. I heard that Fluidamper might take care of it.I installed one and couldn't believe the difference it was 90% better well worth the cost.

easyasone2three

I just put a Centerforce 1 clutch and pressure plate in my 72 454 and now jave a bad vibration between 3-5000 rpm. Steering wheel vibrates. Flywheel was resurfaced, driveshaft balanced, new u-joints and everything else checked and in tolerance. It didn't vibrate with the old clutch. I had read about the problems with Centerforce but went along with it anyway because the guy at my speedshop recommended it. I was going to take it out and remove the weights but no, I think I'm done with the Centerforce.

I went and bought a LUK yesterday and am going to put it in this week.

68/70Vette

When I had my clone L88 engine balanced, after balancing the crank/rods/pistons, etc, the flywheel and clutch pressure plate were added on and the assembly spun balanced again. I think the cluch pressure plate and flywheel assembly needed a small amount of drilling to get neutral balance. So I guess even though the pressure plate assembly is supposed to be perfectly neutral, maybe they don't factory balance them as exact they should. Interesting, when my pressure plate and flywheel were balanced, the clutch disk was not included.

ImBatman

Here is what I found when I pulled mine today.
http://forums.corvetteforum.com/show....php?t=2078420

Budman68

Centerforce will never take the blame. I had a faulty PP that you could not push in at all. I replace about $600 worth of parts they blamed it on and it turned out to be the pressure plate. They came back with test results that made it within spec. Thats funny because it blew out one master cylinder and two slaves. I will never buy another Centerforce. They need to own up to their crap and replace it when a customer calls you. We are not always wrong.

68/70Vette

Any recommendations for an alternate to Centerforce?

easyasone2three

Put the new LUK clutch in today and drove it the 40 miles home. No vibration at all - problem solved. I don't recommend Centerforce for these cars.

FB007

Stock. Unless your drag racing with 600+HP, it's FINE.