Clutch adjustment problems, thin flywheel
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,720
Likes: 19
From: Manhattan Beach Ca
Clutch adjustment problems, thin flywheel
Ever since I put a thinner flywheel on my engine I cant get a correct adjustment set up. I can never get enough pedal travel to completely disengage the clutch. I had to go so far as to drill a new hole in the Zbar upper arm about an inch below the existing hole where the threaded ajustment rod is.
I've got the long 1.5 GM pivot ball and also the thick 1.5 inch TOB. I tried the adjustable pivot stud before but still ran into the same problems although I had the thinner TOB 1.25.
Just want to know if anyone else has run into this problem with a thinner flywheel?
I've got the long 1.5 GM pivot ball and also the thick 1.5 inch TOB. I tried the adjustable pivot stud before but still ran into the same problems although I had the thinner TOB 1.25.
Just want to know if anyone else has run into this problem with a thinner flywheel?
Safety Car
Joined: Aug 2000
Posts: 3,711
Likes: 43
From: San Antonio TX
Sure. You have upset the placement and clearance specifications of the parts. While this link deals with making things right when it comes to the factory hydraulic stuff, it is a primer on the problem: http://www.goodson.com/store/templat...0dac1d456720dd
It would seem with a proper depth TO bearing and the longer stud that it should bring it within reach, though. But how much thinner is the flywheel? There is a reason why some race and "tuner" parts are just not a good idea for the street.
It would seem with a proper depth TO bearing and the longer stud that it should bring it within reach, though. But how much thinner is the flywheel? There is a reason why some race and "tuner" parts are just not a good idea for the street.
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,720
Likes: 19
From: Manhattan Beach Ca
gerry that's interesting they are talking about only .025-.050.
From my measurements I'm over .200 thinner which I thought going from the 1.25 TOB to the 1.50 would compensate along with long GM stud. Obviously more is needed it looks like.
From my measurements I'm over .200 thinner which I thought going from the 1.25 TOB to the 1.50 would compensate along with long GM stud. Obviously more is needed it looks like.
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,720
Likes: 19
From: Manhattan Beach Ca
I went ahead a pulled tranny and took GM 1.5 pivot ball out and put back adjustable but first set to 1.7. That was too long and TOB was squished against fingers so backed it off to 1.6. Still no major change in pedal travel and I still have to use new second hole in Zbar.
Only conclusion now since I've exhausted all possibilities is heavy duty clutch pressure plate must require more finger depression distance than standard clutches. It works fine with new hole but a little stiffer on the pedal.
Only conclusion now since I've exhausted all possibilities is heavy duty clutch pressure plate must require more finger depression distance than standard clutches. It works fine with new hole but a little stiffer on the pedal.
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
I just saw your post I have been on vacation. I had a similar problem when changing to different flywheels and a Lakewood bellhousing. I went and got an adjustable ball stud and worked at that. A PIA because you have to keep removing the trans but I finally did get it correct height. I removed the stud and welded it so it would not move and it worked fine for years. I used the standard holes in the linkage but it did require using the entire pedal travel for good engagement/disengagement. I used the TOB for the Centerforce PP I was using. I tried both the long and short GM ball studs bit it just would not get the proper pedal travel. My clutch fork was very close to the firewall also. Never hit but was close.
Team Owner
Joined: Apr 1999
Posts: 21,953
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Gordon you previously posted a nice picture of your clutch rod assembly. Maybe include it in this post.
Sufer69. The long GM ball is 1 3/4 inches. I went through this with my Auto - M conversion with the Kiesler TKO 600. I use a 22 pound billet steel 168 tooth for 11 inch clutch. My flywheel is machined thinner to loose weight. I choose to use the Center force DFX clutch.
Well the kiesler kit had the short pivot ball the clutch would not dissengage! I just wanted to kick Kiesler because of their lack of forthought.
But I live near Summit racing and I went over and bought all these adjustable units and every one was expensive crap that you would have to dork with taking the tranny in and out trying different settings. The long 1.750 inch common GM part number long pivot works fine for me.
I do have the adjustable upper Z-bar to fire wall threaded clutch rod though. I also dilled a lower hole on the Fame side of the Z-bar to make it a shorter petal throw makes the clutch fork go farther. So my adjustment is above and not some pivot ball that the tranny covers.
You want to set the fork bearing to fingers very close. like .050. It is about impossible to see with my Lakewood bell housing.
Sufer69. The long GM ball is 1 3/4 inches. I went through this with my Auto - M conversion with the Kiesler TKO 600. I use a 22 pound billet steel 168 tooth for 11 inch clutch. My flywheel is machined thinner to loose weight. I choose to use the Center force DFX clutch.
Well the kiesler kit had the short pivot ball the clutch would not dissengage! I just wanted to kick Kiesler because of their lack of forthought.
But I live near Summit racing and I went over and bought all these adjustable units and every one was expensive crap that you would have to dork with taking the tranny in and out trying different settings. The long 1.750 inch common GM part number long pivot works fine for me.I do have the adjustable upper Z-bar to fire wall threaded clutch rod though. I also dilled a lower hole on the Fame side of the Z-bar to make it a shorter petal throw makes the clutch fork go farther. So my adjustment is above and not some pivot ball that the tranny covers.
You want to set the fork bearing to fingers very close. like .050. It is about impossible to see with my Lakewood bell housing.
Last edited by gkull; Jul 26, 2010 at 10:50 AM.
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
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