Clutches... What are you using!

[StephenB]

My last few threads have given me some great feedback so I figured I would get some more advice!

I had an ACT 4 puck spring type clutch before but it didn't last as long as I thought it would. They also offer a 4 puck solid, and a 6 puck solid or spring type. Not sure if one type would last longer than another one and/or why I would pick one over another. Help me out! And post your suggestions on good clutches! I want to make sure it lasts the entire devil in the dark weekend!

Stephen

[lawtonglenn]

.

Stephen, we used to use the 6 puck type...

however, our biggest problem over the years has been keeping the transmissions intact...
in fact, for our three RX7s we have in stock six additional transmissions,
three in rebuild, and three ready for use... if you remember one NHMS race weekend
last year I broke the tranny in the 14 car on the first lap of qualifying, trailered
home, swapped another tranny in in 1.5hrs, and returned to win the race after starting
from the back

what does this have to do with clutches you ask? well, we found that downgrading the clutch
from a six puck racing clutch to a "stage 1" exedy street performance clutch greatly
reduced the incidence of transmission failure ... our measly 175hp isn't what the
racing clutches were created for... the street performance ones work just fine, and they put
less shock load into the tranny ... here is the exedy page:

http://www.exedyusa.com/race_clutch/...e_1_clutch.php

best!
Glenn

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[StephenB]

Ya but I am getting close to 270 hp in my ITR RX8

[Dano77]

Use a Clutch plate with springs!!!!!!!!!

I dont know if Glen made that clear enough for you.


Clutch Plate With Springs keeps the shock out of the transmissions.

Ive broken more transmissions in one weekend than I brought spares for due to the solid center cutch plates.

Dan

70,77,79 IT7

[StephenB]

Ok so should I just replace it with the 4 puck spring type that was in it? I think the 6 puck would just weigh more and "bite" more which is what I don't need.

My dad said to get a regular street performance spring type clutch. He said my low torque rotary thing is nothing like his mustang that needed a puck type clutch.

Stephen

[Ron Earp]

We use a spring type clutch as it is kinder to the driveline. We used to use the puck type in the SMs but I didn't really see any difference in times but certainly felt that the clutch was harder on the driveline. I have never used a puck type in an IT car.

I think there is more bang for the buck in getting the lightest pressure plate you can find. Spec and others make pressure plates with an aluminum ring surfaced with a replacable iron friction surface. These drop a lot of rotating weight, the old Z one I used to use was around four or five pounds lighter than a stock one.

[Tim Dugan]

not to hijack this thread but i have a solid 4 puck in the corrado do the masses think that may also be killing the inner CV joints and causing them to break?

[Flyinglizard]

All of the rotating parts will last much longer with the sprung hubs.

Your axles may be breaking due to lack of plunge space. Or just crappy parts.

[mossaidis]

I only use sprung aftermarket clutches in the little civic, albeit ~132 whp ain't much compared to ITS/R cars. Yet lighter, faster engaging clutches that can withstand more heat w/o killing your tranny is critically important. I went from stock oem clutch, to a ACT 6-puck and now I am using a Clutch Masters 6-puck.

- OEM had a soft fine, smooth feel but would go spongy 10 minutes into an aggressive session. I only used it for 2 track events.

- The 6-puck ACT clutch was married with the HD pressure plate. Great touch, not jerky, smooth fast engagement, perhaps a bit early though nothing that could not be managed with good foot work. After 3 seasons it gave up. The pressure plate warped causing the clutch to drag, making it impossible to change gears = a DNF at LRP in the 2011 season.

- The clutch masters setup is solid. Again, not jerky, smooth fast engagement, yet unlike the ACT, a bit late in engaging though nothing that could not be managed with good foot work and timing of gear shifting.

[StephenB]

I only use sprung aftermarket clutches in the little civic, albeit ~132 whp ain't much compared to ITS/R cars.

I was joking about the 270 hp .

Thanks for the info!

Stephen

[Matt93SE]

I've been using an organic disc w/ sprung hub for upteen years and haven't had a problem. ACT or Exedy.

I typically get about 3 seasons on the friction disc before they start slipping under hard use, and then I change the disc out. Haven't bought a new pressure plate in ~10 yrs.

the last disc I bought, I tried to go to a 4/6 puck sprung hub ACT disc. however, it won't fit. revisions in the HD pressure plate and/or sprung hub design now have interference. The sprung hub OD is about 1/16" (or less) too large for my older pressure plate ID. If I were to go to an unsprung hub or to replace the pressure plate with a newer one with slightly larger ID, then all would be happy again. Instead, I just milled the mounting flange on the flywheel down about 0.02" and stuck the old disc back in. free fix.

....... As others have said, one of the main issues with longevity of the transmission is to use a sprung hub clutch. I also got the same comments from ACT and from G-Force when I was shopping for a dog box. going to a superlight unsprung hub causes higher shock loads inside the trans and thus gear failures.

[DavidM]

There's a thread over in the Nissan forum where I asked about clutches for my 240sx. There's lots of info on the web about sprung vs unsprung as well. You're probably going to find that there's as many types and manufacturers of clutch used as brake pads. The puck type discs get more on/off with less pucks, but weigh less. The springs absorb some of the driveline shock, but can fail. You also have to figure out the pressure plate as the springs in the pressure plate determine clamping force. I wound up going with an ACT 6-puck unsprung disc with their heavy-duty pressure plate and it seems to work fine in my car. YMMV.

David

[Simon T.]

I bought a Exedy "stage 1 street" clutch for my RX-7, unsure of what it DID have, but it felt like a regular street clutch.

[Matt93SE]

The Exedy "Stage I street" is about the same as the ACT Hd/Street disc. it's good for about 50% more clamping force than the stock clutch, but typically lasts quite a bit longer.

the fun part is Exedy makes the clutch discs for ACT... I think ACT uses a "custom" marcel in the center, but the center section of several ACT clutches Ive installed had Exedy/Daikin laser-etched onto the surface. hmmmm.
Can't comment on the source of their pressure plates, but they look strikingly similar to Exedy other than the bright yellow color. then again, a clutch looks like a clutch looks like a clutch.

[erlrich]

Interesting discussion. Just to add one more data point to the mix; I've been running an ACT HD plate with a 4-puck disc in the 240SX since I put the new engine in back in '07. Granted, I only run a few events per year, so I probably have only 15-18 weekends on the engine since then, but so far I have had zero issues with the clutch or tranny (having said this, I've probably guaranteed that both explode the next time I go on track...). The engagement doesn't feel any more harsh than the oem clutch did, in fact about the only time I notice any difference is when driving around the paddock in 1st gear. I can slip the clutch just like the stock one when putting it on/taking it off the trailer, and on track I can't tell any difference (other than it doesn't start slipping after 15 mins...). I won't hesitate to use the same disc again when it's time to freshen up.