Does my clutch adjustment look correct?
Thread Starter
Burning Brakes
Joined: Dec 2001
Posts: 921
Likes: 1
From: Albany WI
Does my clutch adjustment look correct?
I have a 25 lb flywheel, a Lakewood bellhousing with an engine plate, and a Centerforce DF clutch and throwout bearing. I calculated that the distance from my pivot ball to the back of the bellhousing with my combination should be about 4.41". This would require a pivot ball of approximately 1.8". My Lakewood adjustable one will not extend that much. So I purchased the longer 1.68" GM one to see how it would look.
I have also seen mentioned that the angle of the clutch fork should be almost parallel with the engine block (about 5-7 degrees closer to the engine block) when the throwout bearing is resting on the clutch. It is hard to determine what is parallel, with the curvature of the fork. So here is a picture with everything installed and the throwout bearing resting on the clutch. There is a little less then an inch of travel in both directions before the fork hits the bellhousing. Does this look like it is going to work, or should I try to find a pivot ball that is about an 1/8" longer? Thanks in advance for your help.
I have also seen mentioned that the angle of the clutch fork should be almost parallel with the engine block (about 5-7 degrees closer to the engine block) when the throwout bearing is resting on the clutch. It is hard to determine what is parallel, with the curvature of the fork. So here is a picture with everything installed and the throwout bearing resting on the clutch. There is a little less then an inch of travel in both directions before the fork hits the bellhousing. Does this look like it is going to work, or should I try to find a pivot ball that is about an 1/8" longer? Thanks in advance for your help.
Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 38
From: Fremont CA
NO! that pivot ball is for a flat spring pressure plate, if you install it, you will probably end up hitting the throw-out fork on the firewall. You need the shorter pivot ball.
Call Wilcox and find out which one is the shorter stud.
Link: http://willcoxcorvette.com/advanced_...cPath=1735http
Call Wilcox and find out which one is the shorter stud.
Link: http://willcoxcorvette.com/advanced_...cPath=1735http
Thread Starter
Burning Brakes
Joined: Dec 2001
Posts: 921
Likes: 1
From: Albany WI
NO! that pivot ball is for a flat spring pressure plate, if you install it, you will probably end up hitting the throw-out fork on the firewall. You need the shorter pivot ball.
Call Wilcox and find out which one is the shorter stud.
Link: http://willcoxcorvette.com/advanced_...cPath=1735http
Call Wilcox and find out which one is the shorter stud.
Link: http://willcoxcorvette.com/advanced_...cPath=1735http
Thanks for your input, but I am even more confused now. Doesn't the shorter pivot ball bring the fork closer to the firewall when the pedal is depressed? I am far from an expert. What am I missing here?
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
My 434 ci motown uses the GM 1.68 inch longer pivot ball.
I have the 1/8th inch thick block saver plate between the Lakewood bell housing and the block. Effectively spacing the throw out bearing farther back requiring the longer pivot ball. I also use the 22# machined thinner billet steel 168 tooth flywheel. This mounts the pressure plate fingers farther forward. The stock shorter pivot ball sent with the Kiesler kit could not even release the clutch. Hence the longer pivot ball. I also drilled two lower holes in my Z Bar. That gave me a greater range of adjustability of where my throw out bearing was located. The bearing should have .040 or so static clearance. I never could figure out how you could ever measure that with the tranny in a car and a little side opening on the Lakewood bell housing.
I have the 1/8th inch thick block saver plate between the Lakewood bell housing and the block. Effectively spacing the throw out bearing farther back requiring the longer pivot ball. I also use the 22# machined thinner billet steel 168 tooth flywheel. This mounts the pressure plate fingers farther forward. The stock shorter pivot ball sent with the Kiesler kit could not even release the clutch. Hence the longer pivot ball. I also drilled two lower holes in my Z Bar. That gave me a greater range of adjustability of where my throw out bearing was located. The bearing should have .040 or so static clearance. I never could figure out how you could ever measure that with the tranny in a car and a little side opening on the Lakewood bell housing.
Last edited by gkull; Apr 28, 2010 at 09:54 AM.
Thread Starter
Burning Brakes
Joined: Dec 2001
Posts: 921
Likes: 1
From: Albany WI
My 434 ci motown uses the GM 1.68 inch longer pivot ball.
I have the 1/8th inch thick block saver plate between the Lakewood bell housing and the block. Effectively spacing the throw out bearing father back requiring the longer pivot ball. I also use the 22# machined thinner billet steel 168 tooth flywheel. This mounts the pressure plate fingers farther forward. The stock shorter pivot ball sent with the Kiesler kit could not even release the clutch. Hence the longer pivot ball. I also drilled two lower holes in my Z Bar. That gave me a greater range of adjustability of where my throw out bearing was located. The bearing should have .040 or so static clearance. I never could figure out how you could ever measure that with the tranny in a car and a little side opening on the Lakewood bell housing.
I have the 1/8th inch thick block saver plate between the Lakewood bell housing and the block. Effectively spacing the throw out bearing father back requiring the longer pivot ball. I also use the 22# machined thinner billet steel 168 tooth flywheel. This mounts the pressure plate fingers farther forward. The stock shorter pivot ball sent with the Kiesler kit could not even release the clutch. Hence the longer pivot ball. I also drilled two lower holes in my Z Bar. That gave me a greater range of adjustability of where my throw out bearing was located. The bearing should have .040 or so static clearance. I never could figure out how you could ever measure that with the tranny in a car and a little side opening on the Lakewood bell housing.
gkull, I know we have similar setups. Are you using the standard height throw out bearing, or a taller one? Thanks again.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I did not order anything special. It came in the kit and looked like every other one I've seen at work. I repair and install TEX racing 4 speeds in some of our Vintage racing Vettes, Mustangs, and bizzarini's
Last edited by gkull; Apr 27, 2010 at 02:53 PM.
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Melting Slicks
Joined: May 2005
Posts: 2,486
Likes: 71
From: Elkhart Lake, Wisconsin
ttt
Al, did you figure this out? It sounds like Gkull would have a similar setup with his machined flywheel to your aluminum flywheel. How close are you to the fingers of the pressure plate with the fork in the full engaged, arm full forward?
Al, did you figure this out? It sounds like Gkull would have a similar setup with his machined flywheel to your aluminum flywheel. How close are you to the fingers of the pressure plate with the fork in the full engaged, arm full forward?
Thread Starter
Burning Brakes
Joined: Dec 2001
Posts: 921
Likes: 1
From: Albany WI
If I had to guess, I would say 1/2", which seems like too much. I have read though where the Centerforce DF clutches should have a little more clearance. I should be able to adjust the rod to bring it closer, but I don't know if I will have enough travel to disengage. I have it all pulled apart now and I'm getting it ready to haul down to the shop in the morning. I will take another look at it when I get it back together. I'm hoping for the best, but prepared for the worst. It's not a good situation, but I've run out of time.
Drifting
Joined: Apr 2002
Posts: 1,720
Likes: 19
From: Manhattan Beach Ca
I can tell you that I went from stock flywheel to .200 thinner and bought an adjustable pivot ball and still could not get the thing right.
There seems to be no room for error in the setup. I'm using the short TOB. I'm thinking of returning to stock flywheel at my next clutch replacement just to get it all right.
There seems to be no room for error in the setup. I'm using the short TOB. I'm thinking of returning to stock flywheel at my next clutch replacement just to get it all right.
