Input on Clutch Choices
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,457
Likes: 9
From: Minneapolis MN
Input on Clutch Choices
I'm gonna be putting in a new clutch. I've pretty much narrowed my choices down to the Spec Stage 2 or a Centerforce Dual Friction. The car is an 89 with built motor. I'm pushing about 310 hp and 389 ft-lbs at the rear wheels. I have the single mass flywheel already. I think it has the Spec Stage 2 in there now, though I am not sure as the previous owner did it before. My old 88 had the Centerforce dual friction and I liked it better than what's in my 89 now, but I don't know how it will handle the power my 89 makes (my 88 was more mildly built).
I don't race at all but I do drive it hard sometimes when I get out on deserted back roads. Any thoughts on my choices? Any other recommended options?
I don't race at all but I do drive it hard sometimes when I get out on deserted back roads. Any thoughts on my choices? Any other recommended options?
Melting Slicks
Joined: Apr 2007
Posts: 2,616
Likes: 111
Torque can help kill a clutch too........hp is a just a function of torque over the RPM range....alot of clutch damage results upon launching of a car.....that's what moves the car from the launch.....torque
The spec 2 is a good choice even for mild builds but the torque rating you have may be good for the spec stage 2. I run the Spec Stage 2 and so far it has provided the best results of anything I used before with driveability/durability.
The spec 2 is a good choice even for mild builds but the torque rating you have may be good for the spec stage 2. I run the Spec Stage 2 and so far it has provided the best results of anything I used before with driveability/durability.
Team Owner
Joined: Aug 2004
Posts: 21,543
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From: Park City Utah
What is included in the "anything you've used before"?
"At the rear wheels"....which is ~370hp/450tq at the crank. Although a stock clutch MAY hold that fine for the intended use, I'd probably look to upgrade too.
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,457
Likes: 9
From: Minneapolis MN
Yep...the previous owner upgraded because the stock clutch wouldn't handle the current set up. I don't know exactly what's in there now because the invoice only says "perf clutch". But the PO said it's kevlar.
Suckin' gas, haulin' ass.
Joined: Apr 2010
Posts: 1,100
Likes: 8
From: Newport News Virginia
I'm running a Stage 1 SPEC in my 89 pushing 322 rwhp and 345 rwtq. It's a road race car, so I don't use it on the street at all, but it holds the power just fine.
FYI, I'm also running the SPEC aluminum flywheel.
FYI, I'm also running the SPEC aluminum flywheel.
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,457
Likes: 9
From: Minneapolis MN
Suckin' gas, haulin' ass.
Joined: Apr 2010
Posts: 1,100
Likes: 8
From: Newport News Virginia
I would estimate out 100 miles so far. I've never had any slipping or chatter issues at all. I didn't have anywhere to drive it for 500 miles for break-in so I'm just careful about how much I slip it, though with the aluminum FW, you do have to slip it a bit more in order to not stall the car.
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Melting Slicks
Joined: Apr 2007
Posts: 2,616
Likes: 111
then to RAM puck style; that shook the car so violently in reverse gear when slipping the clutch out (espcially on an inclined surface) it would be a matter of time before the whole car was in pieces.....
this SPEC II set up has been a great compromise between a grabby clutch and durability/driveability.
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,457
Likes: 9
From: Minneapolis MN
So I ordered a Zoom clutch that was specced identical to the Spec Stage 2, but I could get it faster so I went for the Zoom. It showed up with the throw out bearing destroyed due to poor packaging. Returned it and now have ordered the Spec Stage 2 I wanted in the first place. My effort to save time and get the car back on the road has resulted in a lost week. The driving season in MN is too short for that to happen. 
856Speed - you're running the Spec Stage 2. How long is the break in period and what are they recommending as far as how you drive during that period? I'm running the steel FW so hopefully chatter won't be an issue.
856Speed - you're running the Spec Stage 2. How long is the break in period and what are they recommending as far as how you drive during that period? I'm running the steel FW so hopefully chatter won't be an issue.
Melting Slicks
Joined: Apr 2007
Posts: 2,616
Likes: 111
So I ordered a Zoom clutch that was specced identical to the Spec Stage 2, but I could get it faster so I went for the Zoom. It showed up with the throw out bearing destroyed due to poor packaging. Returned it and now have ordered the Spec Stage 2 I wanted in the first place. My effort to save time and get the car back on the road has resulted in a lost week. The driving season in MN is too short for that to happen.
856Speed - you're running the Spec Stage 2. How long is the break in period and what are they recommending as far as how you drive during that period? I'm running the steel FW so hopefully chatter won't be an issue.
856Speed - you're running the Spec Stage 2. How long is the break in period and what are they recommending as far as how you drive during that period? I'm running the steel FW so hopefully chatter won't be an issue.
Tom at Carolina Clutch told me to give it a 500 mile break in period wereby he called for "easy driving." No hard launches, hard exceleration pulls, etc..etc....also try to make stop and go trips here and there and combine it with highway driving....basically didn't want me to hammer the thing for 500 miles.........not sure I followed all of that but for the most part I did; I take care of my car since I have a few bucks in it.....understatement.....
You will have better driveability with the steel FW....the steel FW makes it a little easier to move off the line without higher revs.....I actually have a steel FW in storage....may go to that one day, but the aluminum FW has it's advantages too.......
You will like the SPEC clutch! I hope!
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,457
Likes: 9
From: Minneapolis MN
Well,
Tom at Carolina Clutch told me to give it a 500 mile break in period wereby he called for "easy driving." No hard launches, hard exceleration pulls, etc..etc....also try to make stop and go trips here and there and combine it with highway driving....basically didn't want me to hammer the thing for 500 miles.........not sure I followed all of that but for the most part I did; I take care of my car since I have a few bucks in it.....understatement.....
You will have better driveability with the steel FW....the steel FW makes it a little easier to move off the line without higher revs.....I actually have a steel FW in storage....may go to that one day, but the aluminum FW has it's advantages too.......
You will like the SPEC clutch! I hope!
Tom at Carolina Clutch told me to give it a 500 mile break in period wereby he called for "easy driving." No hard launches, hard exceleration pulls, etc..etc....also try to make stop and go trips here and there and combine it with highway driving....basically didn't want me to hammer the thing for 500 miles.........not sure I followed all of that but for the most part I did; I take care of my car since I have a few bucks in it.....understatement.....
You will have better driveability with the steel FW....the steel FW makes it a little easier to move off the line without higher revs.....I actually have a steel FW in storage....may go to that one day, but the aluminum FW has it's advantages too.......
You will like the SPEC clutch! I hope!
The clutch that was in there was a kevlar disc. Not 100% sure of the brand, but it may have been the stage 2. I got pretty used to it with no real driveability issues...until it went bye, bye on me, of course. So I'm not expecting to have any real issues.
Melting Slicks
Joined: Apr 2007
Posts: 2,616
Likes: 111
I've had good luck with it, but I don't get to the drags very often or things like that....I run it with a Fidanza alum. FW with no issues at all (so far) and I have had this clutch for a while......
I think you will like it......may be a little chatter when slipping it out but not anything crazy or something you can't live with.....
I think you made a good choice......
I think you will like it......may be a little chatter when slipping it out but not anything crazy or something you can't live with.....
I think you made a good choice......
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,457
Likes: 9
From: Minneapolis MN
I'll continue this thread with a shout out to Enjuku Racing out of Florida. They somehow managed to get my Spec Stage 2 parts to me a day earlier than promised! With a little luck I'll be able to end this thread tonight with a report on how well the parts work! It'll sure be nice to be behind the wheel of my Vette again.
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,457
Likes: 9
From: Minneapolis MN
Well, I managed to get 75 miles on my new Spec Stage 2 clutch already. My driving consisted of a 50/50 mix of surface streets and freeways. Lots of start/stops and shifting with all the rush hour traffic I navigated. It works flawlessly! No chatter, take up is perfectly smooth. Overall, I'm satisfied and sure glad to have my Vette back on the road. Now to rebuild those headlight motors....