It seems that puck discs are the norm for FI guys. They tend to grab harder than a street disc that has more surface area for slippage which is why I suggested the models I did. Didn't realize they slipped enough to cause crank walk...that sucks. Anybody know if ACT has fixed these issues?

 

There has been a thread about redesigned ACT HD disc. They reduced the clamping force in order to address concerns, but there has been some debate as to whether it was just ACT having the problem. Any clutch that puts to much force on the bearings can cause wear.

 

Your clutch slipping doesn't cause crank walk

 

...neither does clamping force. It's release force that potentially causes crank walk. Your "peddle effort" is a measurement of release force. Lots of peddle effort = lots of realease force.

Until ACT made changes in their clutch design they had the most release force of any aftermarket clutch manufacturer for the S2000. They now have 25% less release force which should put them at or slightly above the other clutch makers and most likely in a safe zone for end users.

Only ACT and Clutchmasters use the OEM style FOUR spring hubs which are generally less noisy or not noisy at all compared to Spec, Competition etc who use a SIX spring proprietary hub which tends to be noisy on the S2000 due to a difference in operational harmonics.

Aftermarket clutch makers rate their clutches according to flywheel torque not rear wheel torque. Rear wheel torque = .85 X flywheel torque. If you're looking to hold 225 rwtq you'll need a clutch rated at at least 265 fwtq plus a 20% service factor = 331 fwtq which is not hard to come by.

In all cases disableing the clutch safety switch is a MUST DO to maximum thrust washer life. This allows you to start the car without putting any force on the thrust washers when they are not yet lubricated.

 

OJR said that the 310whp low boost AP2 kit didn't require a clutch upgrade, but the 360whp high boost kit does as the clutch starts to slip.

Using that, we can get a conservative envelope:
HP = (TQ * RPM) / 5250 //// TQ = 5250 * HP / RPM

MIN = 310whp @ 8600RPM = 190 ft-lbs = Factory clutch OK
MAX = 360whp @ 8000RPM = 235 ft-lbs = Factory clutch slips

So around 210 ft-lbs of torque is where the factory clutch starts to lose grip.
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Also, has anyone on the board used Centerforce products on their S2000? I had one of their clutches on my old Dodge Stealth.

 

I believe the competition stage II clutch has been recently redesigned to reduce most, if not all clutch buzz and noise...you might want to contact them about it. Also, it is full face which means it should last longer than puck.

 

if you could link that thread thatd be great, setups like that i have seen a lot of people using the HTG package with the oem disc.