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Best Clutch???

2K views 24 replies 20 participants last post by  Don N 
#1 ·
Hey guys I have a 351 punched out to 427---500+ hp, what clutch would you put behind that?? I tried a Zoom hi perf clutch (not bad) and am in the process of replacing my Centerforce II clutch(slipping bad). I drag a little and get on the track once in a while any suggestions?? Thanks---Don
 
#4 ·
I'm pretty sure the King Cobra is more of a entry level performance clutch.

I would also consider my SPEC stage 1 an entry level performance clutch similar to the King Cobra.

Although I've never used one, I've heard good things about SPEC's KEVLAR STAGE 2 and STAGE 3 clutches. Since the car is so light a STAGE 2 Kevlar may do the trick. I've heard these clutches tend to be a little "grabby".--Dan

http://www.specclutch.com/specMain.html
 
#5 ·
I have had a SPEC Stage 2 clutch (Kevlar) in mine for 2 years now and it has been trouble free. Nice street manners and has seen many 1/4 mile passes with no complaints. My motor has about 500 ftlbs at the flywheel.

I had put a RAM HD clutch in mine when I rebuilt the motor to go in the FFR but it couldn't handle the torque of the motor. After I had it dyno tuned it would slip really bad in 3rd gear and higher. In the end the clutch lining came apart from the heat.

One thing with the Kevlar and Carbon clutches is that it takes a while for them to bed in. You have to run them in with around town driving before really leaning on them hard. I had to put about 300 miles on mine before it would lock up solid.
 
#6 ·
What about a Centerforce Dual friction? I haven't used one personnally but my friend has one in his firebird and raves about it.

-SGC
 
#7 ·
I stopped using the Centerforce II after my 99 Saleen grenaded one after the 5th pass.... sheared half of one side of the disc. The car makes 315hp/415tq to the wheels so it's a bit under what you are looking at. I replaced the CF-II with a Spec III. 2 years later and it's holding up very well (knocks on head...) It's *very* grabby, almost an on/off switch and takes a bit of getting used to.

I would put another one in the Saleen in a heartbeat, but I'm not so sure about car as light as a Cobra.
 
#8 ·
Check out the QuarterMaster flywheel , clutch and pressure plate. This is an aluminum flywheel and pressure plate.....a bit pricey but well worth it. I have their parts in my Panoz GTS and that pulls about 445 HP at the crank. It will handle the 500 HP you mention. The FFR car is light enough that the aluminum system works very well.
 
#9 ·
When I ordered my TKO600 from Mike Forte, he recommended (and of course sold me) a Weber clutch. My 408W will be putting out around 500 lb/ft of torque. Give him a call and ask him for a comparison of the various clutches.
 
#10 ·
I went with Weber dual friction from Forte's for the same reason as Steve. The pedal pressure is not all that bad and seems less than my old kingcobra. When I took my donor apart many yrs ago it had a chewed up bellhousing and a centerforce clutch minus 3 weights.
 
#11 ·
My 351W is making 510-520HP and I have had 7000 trouble free miles from my Spec II clutch which I have smacked around quite regularly on the street as well 8-10 launching track passes. The Spec II is not a Grabby clutch but once you engage has a very solid feel with no slippage.
 
#18 ·
I have a SPec stage 2 in my mustang (331 stroker) - great clutch - very streetable - slips and grabs when you want it to. The stage III I have heard is much more of an on/off type clutch - less streetable I would think especially in any stop and go traffic. I just did a little burn out tonight, so I can give the stage II 2 thumbs up.
 
#19 ·
Here's my take. Get a Spec stage 2. I'm using a stage 3 but I dragrace more than most and in reality a stage 2 probably would have been fine. I don't think you'll find it too graby as these cars are so light. Pedal pressure is firm but still easy.
 
#20 ·
Are the Spec stage II clutch assy's compatable with the stock type clutch cable from Ford?
 
#21 ·
Don,
Unfair, unfair!
Please don't change clutches!

I have a secret plan to get better traction and if your cluch starts to work, it would be for naught as you would zoom ahead of Old 3850 again like you did this year!

Don "Clutch Slipper" Newman beats Larry "Tire Slipper" Johnson

12.745 vs 13.089
 
#23 ·
I deal in and did a lot of developement of the Quartermaster systems. There are 3 that we use depending on hp and torque.
Base 18lb clutch and flywheel assy with organic disc. Hold 500lbft of torque- $895
Base 18lb clutch and flywheel assy with composite disc. Holds over 600lbft of torque- $895
Competition 18lb clutch and flywheel assy with dual composite discs. Holds over 800lbft of torque.- $1095

This is a complete flywheel and clutch assy w/t-out bearing. It will rev really well because of the rotating mass you are taking out of the rotating assy. All the friction components in the assy are rebuildable so you never need to buy a new assy. We have this system in several road race cars with major hp with no problems.
When you add up the costs of an aluminum flywheel and good clutch assy, the costs are comparable.
 
#24 ·
I have the Spec Stage III in mine. Pedal effort is firm, but not bad by any means. It is a bit grabby. Ive only driven short distances around the block since im not registered yet, i would bet with more seat time i'll learn the "sweet spot" where it engages and much of the grabiness will go away.

I have barked the 315 Nitto drag radials more than a few times on accident....maybe a few times on purpose too....
 
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