View Full Version : Race Clutch Comparison


69Nova
May 30th, 06, 07:21 PM
Race/Street Clutch/Clutch Disc Comparison



We are currently rebuilding our car to be driven at an 80% Race / 20% Street ratio. Weight is approximately 3200lbs. Rest of the car is as follows:



355 in. iron block

Sportsman II 64cc heads

Solid flat tappet cam with 0.533” / 0.544” lift

10.63:1 Static Compression

Weiand tunnel ram with (2) 450cfm Holley’s

Jerico 4spd. Clutch-assisted trans.

Ratios: 2.93/1.88/1.33/1.00

4.88 Rear gear in 12 bolt posi rear.

30x9 Goodyear slick



Currently we have an Hays 10.5in. Competition Borg & Beck pressure plate with 2500lb. static force, mated to a stock Chevrolet flywheel. The input shaft for the Jerico is the 1-3/16” x 18 spline Chrysler input shaft. We also have a spare 26 spline Chevrolet input shaft. We would like to use the Chrysler input shaft, as it seems to be what most Stockers with sticks are running. We would like to use our current pressure plate with a new 10.5in. clutch disk with 18 splines. We need recommendations on a disk and entire clutch setup for future reference. I’d like to try to stay away from sintered iron, as it chews at the stock flywheel (which will be replaced eventually anyway, but I’d prefer to remove it from the car in useable condition). Currently, I’m considering the following clutch disks:

Hays Super Connector Sprung Hub Organic
RAM 1000 or 6000 Series sintered bronze
RAM 300M Organic

Does anyone have experience with these clutches or discs?
Could anyone recommend a different disc suited to the car's intended usage?

For the next complete clutch setup, I’m considering the McLeod Soft-Lok, McLeod Street Twin, or something from Rob Youngblood at Advanced Clutches. Certainly, Rob’s would be the best, but I’m afraid of losing all streetability, not to mention probably being higher priced than the first two. I’m choosing to stay away from SPEC clutches. I’m leaning towards the Street Twin due to driveability and a perceived similar holding power to the Soft-Lok. The Soft-Lok may be easier on parts, but I believe is also more expensive. The Street Twin seems to get good reviews from those who have used it, as does the Soft-Lok, although it seems that nearly all Soft-Lok users are strictly racers. I’d have to get the Street Twin with a Chevrolet flywheel and Chrysler-splined discs, which may cost a little more. What are the advantages and disadvantages of each setup? Which has more holding power? Which provides more streetability? Which is easier on parts? Has anyone ever used a Street Twin with a Jerico? What OTHER clutch setups would you recommend for the intended usage of the car? For anyone who has used either of these clutches, what is the average life expectancy you have experienced before a rebuild is needed? What kind of times have you turned with either setup? Any other opinions?

smits67
May 30th, 06, 08:02 PM
I have experience with the Ram 300 organic. I liked it, and it worked well....but so far the Centerforce dual friction gold clutch has proven to last longer and hold just as well (so far, the Centerforce DF clutch has 8 years of street/race duty. Best pass using a small block and a DNE 5-speed has been 11.05 in the quarter in a 2900lb 55 Chevy. It is showing no signs of failing at this time).
I have also used the 6 puck sintered iron disk, but found it to be horrible for any sort of street driving.
Overall, the Centerforce has been my best all around dual purpose(street/race) clutch.
Chris

dragon0123
Jun 2nd, 06, 10:24 AM
Ive been running a centerforce dual fricting in my mostly street car.. way overkill im sure, but it has been fine by me.. has no problems holding my 350 motor..

496z/28
Jun 3rd, 06, 07:56 PM
contact Clutch Masters........www.clutchmasters.com.......

They always give me awsome tech advice, have bought many set-ups from them. What they have recommended has always worked!!

sc68z28
Jun 3rd, 06, 09:37 PM
I'm using the McLeod Street Twin, in my Camaro, 50/50 street/strip.
Have about 1000 miles on it so far, its working great. Smooth starts and seems to bite well at the track (4500 to 5000 rpm at launch).
I was having traction problems when it ran a 10.33 et, 1.65 60'.

With a larger rear tire, I snaped the pinion gear shaft on my 9". I think the traction problem is fixed.