VIBRATION PROBLEM from 6-Puck clutch on start ??????????????

[nissias]

Hello guys.
I am about to replace my clutch with a new clutch kit and my mechanic was worried that the 6-puck disc I took to him might cause a lot of vibration on stop and go situations that will end up damaging the gearbox. Has anyone fitted a 6-puck clutch similar to mine and did anyone have any problems with the car (like vibration on start)?
More precisely I have bought a SPEC Stage 3 High clamp pressure plate, 6 puck carbon semi-metallic friction with high torque sprung hub and disc assembly with the bearing and tool kit. I hope this helps.
Any help will be greatly appreciated as for me to know if I can fit the clutch kit with the 6-puck disc or not!

Cheers,
Nik

[RayD]

Hi Nik,

To save going into great detail, it just seems a daft idea.

Your mechanic thinks it will vibrate and be unsuitable for normal road use, and you won’t be able to see it once its fitted. If it needs a new clutch put a standard one in.
Regards,
Ray

[nissias]

but i don't want to put a standard one but a better one. That's why I bought the 6-puck clutch kit. I know some members have used 6-puck discs and I am waiting for their feedback if they have been experiencing any problems.

[Doc Fizzix]

You need to talk with Dave M, he was very helpful with me on this issue

But from everything I have heard about these, they to "chatter" a bit until you learn how to use them. They are not the best for everyday easy-going driving.

[nissias]

i don't use the car that much in traffic. I only use it on highways and roads going up to the mountains

[Sy V]

This is exactly the reason why I've recently changed back to a normal clutch plate.
The combination of a six puck clutch and lightweight flywheel gave chatter and a lack of 'feel' that was so pronounced that I never got used to it. I'll put it back in the track car (for faster get away) but I wouldn't put it in my road car again.

[davidjt]

Not a lot of help if you've already bought one, but for what its worth I've been delighted with the SPEC Stage 2 (Kevlar) clutch from Horsepowerfreaks.com

One of the (very) few things I got right first time!

[nissias]

This is exactly the reason why I've recently changed back to a normal clutch plate.
The combination of a six puck clutch and lightweight flywheel gave chatter and a lack of 'feel' that was so pronounced that I never got used to it. I'll put it back in the track car (for faster get away) but I wouldn't put it in my road car again.

did it cause any damage?

[Dico]

Mines 'just' about bareable for road use.
I think a new stock clutch would be my choice if I were to stick at 200bhp and have to do it again.... Though I don't intend on sticking at 200bhp

[nitroman]

I had an even more aggressive 4-puck full-metallic disc & heavy-duty clamping-plate on my nitrous Elan.

At first I thought I had created a very unpleasant-vehicle for street use but as I had ruined the stock and then the +90% clutches in short order, learning to live with it was my only choice.

It took me 2-weeks of practice and dedicated attention to start a stopped-car without clutch chatter, but it can be done. If you forget it's there; if your mind is on something else... it will chatter. Still, I don't think it will do engine damage. The chatter usually occurs when you treat it like a normal clutch and take-off at low-RPM. When you perform a 'race-start' the RPM is high enough that you do not have any chatter. The worst that will happen is you'll treat it like a stock clutch and stall the engine. In Atlanta that means you'll be rear-ended by the car following you! (which is much more of a concern than engine damage!!!)

My take is that you don't need to worry about the shudder causing drivetrain damage. You can make a non-streatable clutch streetable, just not pleasant. The add for mine said "This clutch is non-streetable."

The question you should ask is, 'Is this my ONLY choice?" If it is, then get it. Knowing it is your only option makes it much easier to live with.

[Doc Fizzix]

For what it is worth

I know we have been down this road a couple time having this same discussion about clutch set-ups and everyone has a different take on the matter but for what it is woth I had a clutch built for me and to my specs that was not a puck clutch but used a stronger pressure plate and was rated up to 325 hp; the point I am tryinng to make is that there are places out there that will work with you and build a clutch set-up to your specs. If you just order a pre-made clutch you may not be getting the best match-up for your use or needs.

[lotusgirlmarie]

Weird.... I have the 6 puck clutch and uprated preasure plate with the lightened flywheel and rarely have chatter issues...... and I drive my car on city streets every day. I bought everything from the same place the forum has picked up the Fidanza flywheels about 3+ years ago. I also change out the tranny fluid to fresh (30wt racing oil). Weird......

[nissias]

I had an even more aggressive 4-puck full-metallic disc & heavy-duty clamping-plate on my nitrous Elan.

At first I thought I had created a very unpleasant-vehicle for street use but as I had ruined the stock and then the +90% clutches in short order, learning to live with it was my only choice.

It took me 2-weeks of practice and dedicated attention to start a stopped-car without clutch chatter, but it can be done. If you forget it's there; if your mind is on something else... it will chatter. Still, I don't think it will do engine damage. The chatter usually occurs when you treat it like a normal clutch and take-off at low-RPM. When you perform a 'race-start' the RPM is high enough that you do not have any chatter. The worst that will happen is you'll treat it like a stock clutch and stall the engine. In Atlanta that means you'll be rear-ended by the car following you! (which is much more of a concern than engine damage!!!)

My take is that you don't need to worry about the shudder causing drivetrain damage. You can make a non-streatable clutch streetable, just not pleasant. The add for mine said "This clutch is non-streetable."

The question you should ask is, 'Is this my ONLY choice?" If it is, then get it. Knowing it is your only option makes it much easier to live with.

so the trick with the 6-puck clutch is to rev more at the start?

[nissias]

Weird.... I have the 6 puck clutch and uprated preasure plate with the lightened flywheel and rarely have chatter issues...... and I drive my car on city streets every day. I bought everything from the same place the forum has picked up the Fidanza flywheels about 3+ years ago. I also change out the tranny fluid to fresh (30wt racing oil). Weird......

the guys at SPEC told me that the stage 3 clutch I bought is streetable and better for road use than the stage3+ clutch which was a full round clutch as the stage 3 clutch they sold me is a 6-puck. And maybe as you mention, using a good gearbox oil might be something extra which is good

[Sy V]

did it cause any damage?

Both engine mounting shock absorbers were toasted, so I changed them, but they were original from manufacture and the car had done 106,000 miles.
46,000 of those were mine with only about 4,500 with the six-puck, lightweight flywheel, LSD and upgraded pressure plate.

The only thing that remains in Stripey is the LSD which I wouldn't change for the world.

[lotusgirlmarie]

Engine speed does have alot to do with it as wella s how fast you let out the clutch.

[nitroman]

Ditto above. You will have to develope a new launching technique. As you said higher REVs will be required along with a very keen feel on your clutch foot. You will learn to match engine speeds to clutch engagement. It is almost like learning to use a clutch for the first time, if you can remember what that was like.

[RayD]

It’s not the number of segments on the clutch that will cause it to vibrate. They won’t all be made to a standard in order you could rely on a certain performance from a clutch designated with a six or a four. Depending on the pressure plate and size of the segments it would be possible to have a 4 segment one that was smoother than one with 6 segments.

The one in question has been seen by a mechanic who thinks it will vibrate and cause damage to the gearbox. (A badly produced spline would be a good example of something that would cover both those points) I’d take it back to where it came from and get some assurance that it won’t. The last thing you want is a car that judders if you try to set off with anything less than 4000 revs.

Ray

[nitroman]

The reason for having segmented discs (called pucks) on a clutch disc is to lighten the rotating mass, just like having a lightened flywheel. Because the friction area is diminished, it usually has a longer-lasting but less forgiving surface, like the full-metal surface mine had. I don't think any clutch can be dismissed IF it is the only clutch capable of handling the power your engine produces. As I said before, is it your only option?

I also would not take the word of someone who 'just looked at a picture' of a clutch. Why test-drive a car when you can just look at it, and know everything? As I said, my clutch was advertised as not streetable; yet in practice, it was. (Perhaps I could be an F1 champion!)

[nissias]

the 6 springs found in the middle of the disc are supposed to keep the gearbox trouble-free from any damage as they allign the disc straight at every start