[C2] Which clutch.
Thread Starter
Burning Brakes
Joined: Dec 2017
Posts: 947
Likes: 250
From: Deshler Nebraska
TCracingCA :
OK. You got me curious. Tell the beginner more. All new to picking a clutch. Can you tell me which Dual Friction Clutch, from Centerforce I assume, you used. I am guessing the clutch you tried worked OK. Was this in a C2? What engine, hp and torq ? How was the foot pedal pressure to operate the clutch ? More, less or can not tell much difference in the force needed to operate the Dual Friction clutch ? Did you run a 10.5 or the 11 ? Ugh!
OK. You got me curious. Tell the beginner more. All new to picking a clutch. Can you tell me which Dual Friction Clutch, from Centerforce I assume, you used. I am guessing the clutch you tried worked OK. Was this in a C2? What engine, hp and torq ? How was the foot pedal pressure to operate the clutch ? More, less or can not tell much difference in the force needed to operate the Dual Friction clutch ? Did you run a 10.5 or the 11 ? Ugh!
Last edited by Nelag; Dec 26, 2024 at 09:42 PM. Reason: Adding info.
Le Mans Master
Joined: Apr 2001
Posts: 5,438
Likes: 1,255
From: Sarver Pa
2021 C1 of the Year Finalist - Modified
When I started racing back in the 70's I was talking to my engine builder about a 11" clutch and he asked me why I wanted a 11" clutch. He said , what are doing pulling stumps ? I never bought an 11" clutch again and haven't regreted it. You just don't need it.
Race Director
Joined: Mar 2001
Posts: 14,640
Likes: 4,687
From: Mustang OK
2026 Corvette of the Year Finalist - Modified
2025 c1 of the Year - Modified Winner
2024 C1 of the Year Finalist - Modified
2023 C1 of the Year Finalist - Modified
2015 C1 of the Year Finalist
For sure, I feel the Cutlass needs an 11in clutch.
Race Director
Joined: Jan 2003
Posts: 17,721
Likes: 3,707
From: Central Arkansas
If an 11” clutch is considered an antiquated, truck oriented, stump puller, anachronism - then I can only imagine what they think of the 12” McLeod clutch behind the stroked FE in my ERA Cobra roadster. McLeod clutches, if you look at the specifications, have equal total clamping force in 10.4 and 11 sizes. The only way I figure they can accomplish that with reduced surface area, is stronger springs in the pressure plate. That has to equate to higher force - and pedal pressure - to disengage the clutch. Maybe it’s not that simple - maybe they use a different lever ratio on the fingers to keep the pedal pressure down but I suspect that means more pedal travel distance to fully disengage the disc, which is pretty restrictive in a Corvette foot box. I don’t know if that’s true for all makers but I generally use McLeod so I’m just fine with the big clutches.
Le Mans Master
Joined: Nov 2015
Posts: 7,479
Likes: 2,650
From: Really Central IL Illinois
The 11 inch clutch will have more wear surface and will pull more load before slipping given the same clamping force from the pressure plate.
Back in the day, I ran 11 inch clutches in a 71 Vega with a 302 (400+ HP) and Nash 5 speed on the drag strip. I say clutches as I changed them every year and even then a couple of times on the back of the trailer at the track when they lost the metallic friction face.
The OP is not going for the 11 second passes on the drag strip nor pulling 12,000 lbs. in a grain truck.
I believe the pedal pressure is greater on an 11 inch pressure plate than the 10.4 inch making driving a little more uncomfortable for the older driver and most women. The 10.4 inch clutch assembly will provide adequate service for the lightweight C1 or C2 for thousands of normal spirited cruising miles. The 11 inch assembly will most likely provide more miles in a cruiser. The metallic or ceramic friction facings will be more durable than the organic friction facing.
He must decide how he is driving the car and what durability he needs. I am thinking the LUK 10.4 inch clutch and pressure plate would last him many years. A metallic or ceramic face disc would last longer, but wear the flywheel surface more.
Back in the day, I ran 11 inch clutches in a 71 Vega with a 302 (400+ HP) and Nash 5 speed on the drag strip. I say clutches as I changed them every year and even then a couple of times on the back of the trailer at the track when they lost the metallic friction face.
The OP is not going for the 11 second passes on the drag strip nor pulling 12,000 lbs. in a grain truck.
I believe the pedal pressure is greater on an 11 inch pressure plate than the 10.4 inch making driving a little more uncomfortable for the older driver and most women. The 10.4 inch clutch assembly will provide adequate service for the lightweight C1 or C2 for thousands of normal spirited cruising miles. The 11 inch assembly will most likely provide more miles in a cruiser. The metallic or ceramic friction facings will be more durable than the organic friction facing.
He must decide how he is driving the car and what durability he needs. I am thinking the LUK 10.4 inch clutch and pressure plate would last him many years. A metallic or ceramic face disc would last longer, but wear the flywheel surface more.
Melting Slicks
Joined: Feb 2015
Posts: 2,570
Likes: 1,126
From: Huntsville AL & Hills of Southern TN
When I installed my TKO, we installed the new clutch that came with the kit to replace a Centerforce Dual Friction. Drove it a few times and hated the engagement/feel. Pulled the TKO (big pain) and replaced with all Centerforce Dual Friction parts (not sure who's TO bearing). It is so smooth. I'm sure McLeod has a comparable product, but I went back with what I knew. My non-stock L72 dyno'd at 560 hp. Been a while... I think we installed the 10.4" DF kit. I'm sure this clutch will out last me. I don't drop the clutch but always run it hard several times when driven. Happy New Year. Larry
