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Thoughts on if I should shim or not?

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eclipse012

15+ Year Contributor
183
10
Apr 17, 2008
canada, AB_Canada
I just pulled my transmission out for the second time and replaced the clutch due to clutch drag being an issue. I already adjusted my pedal and master cylinder and tried everything I could to resolve my drag issue, but was unsuccessful. So tranny has came off and I am now tuning a act 2100 6 puck sprung with act streetlight flywheel. My question is since I just got the tranny back on the car I checked the fork position and it sits dead center in the fork hole. The pivot ball and fork and throw out bearing are all oem and brand new. In the pics I marked the exact center if the fork hole with a marker (big black line on top of hole). Let me know what you guys think to add a 1mm shim to the pivot ball or not.
 

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Fork should be more right of center (towards slave) to give it more throw, so yes you need to add a shim. See pic here: http://www.teamrip.com/when_why_and_how_to_shim_pivot_ball_info.html. Adding 1mm (.040") shim minimum should be about right (I ended up using .070"). You'll never know shim amount until you reinstall tranny (just install bell housing bolts and check before installing anything else). The only way to get maximum fork throw is to shim. Many people think lengthening clutch rod or adjusting pedal linkage works but this only changes the pedal position of where clutch disingages. It does nothing to maximize fork throw without which typically results in clutch drag.
 
Fork should be more right of center (towards slave) to give it more throw, so yes you need to add a shim. See pic here: http://www.teamrip.com/when_why_and_how_to_shim_pivot_ball_info.html. Adding 1mm (.040") shim minimum should be about right (I ended up using .070"). You'll never know shim amount until you reinstall tranny (just install bell housing bolts and check before installing anything else). The only way to get maximum fork throw is to shim. Many people think lengthening clutch rod or adjusting pedal linkage works but this only changes the pedal position of where clutch disingages. It does nothing to maximize fork throw without which typically results in clutch drag.

Thank you for the quick reply. Yeah I figured as much as it does need a slight shim, even though I used all oem brand new parts. How far over towards the driver side should it be sitting? Just slightly off center? Or about a 1/4" from center on the drivers side? The thing I'm looking for is a pic of where the fork actually sits when it is in the correct position for maximum slave travel. As to the link you sent me, should the left side of the fork be lined up with the ok center line in the pic?
 
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A non factory PP or flywheel or resurfaced flywheel or flywheel step height will all change the fork position (because PP fingers will move closer or further away from engine which makes fork move) - not just because a non-oem pivot ball, TOB, or fork was used.
[BTW a not your case tidbit: the fork (where it rides on the pivot ball) is what wears, not the pivot ball. So those who replace the pivot ball but not the fork usually result in no change (and then always need to shim).]

I haven't found the fork position limit spelled out anywhere but a safe rule of thumb I determined is: The center line of the fork MUST be to the right of the window halfway point, but not so far as causing the fork left edge to be to the right of the window halfway point. Too far to the right and the throw will be too much causing the PP fingers to hit the clutch disc innerds (eg. springs - this happened to me). Unfortunately you never know where this "too far to the right" position is until it's all assembled and you start the engine and press the clutch to the floor (and then it's too late). So to be safe (and it always works), I never let the fork left edge be to the right of the window halfway point. Of course others may disagree and say you can go farther over but I'd argue that every setup is different and what works for one may not another. Still, if someone knows for a fact you can safely go X" right of center in every setup, please chime in with the details for us. However if you still have clutch drag and are convinced the throw is insufficient, you may consider tweeking it over a little more but you're on your own then. :pray:
Here's mine: http://www.dsmtuners.com/attachment...-fork-shimmed-pivot-ball-at-0-071-jpg.148436/.
Here's another's: http://www.dsmtuners.com/threads/shim-or-not-to-shim.464859/#post-153278064.
 
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Thank you luv2rallye. I'm going to try a 1mm shim today. I will take a pic after and we can see how much a 1mm shim moves the fork. The fork, pivot ball ,throw out bearing all are brand new oem and I still need to shim. I just had my new act streetlight flywheel (which has maybe 200-500 miles on it from trying a different clutch setup) step checked and its at .608[DOUBLEPOST=1411180961][/DOUBLEPOST]So I added a 1mm washer under the pivot ball to shim. Looks like it worked out good. I believe I am in a good spot now. I measure before and after and it looks like a 1mm shim made the fork move approximately a 1/4" check the picks and let me know if you think it looks good or maybe it's possibly too much?
 

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Reviving my own thread LOL. So please read from the beginning. I finally had some time after being occupied with school the last few years to get my clutch adjusted properly. So i'm not happy with where my clutch engages and disengages. I get engagement at about the halfway of pedal travel from the floor while releasing the clutch. Though i feel like the clutch is fully disengaged too close to the top of the pedal travel. It literally feels like its out as my clutch pedal has no more room to move. So i feel that i could be not fully disengaged on the clutch with the pedal all the way out. I have no clutch drag. I tried adjusting my master cylinder adjustment rod in to the point my clutch had hardly any throw and that didn't help. the upper adjustment where the cruise switch is is screwed out completely. Could it be possible that the shim i added was a bit too thick? I'm really not wanting to remove my tranny again.
 
Make a pedal stop. Adjust your clutch to the stop.
 
Is that correct for that clutch? Sounds shallow to me. If a step is shallow. Fingers go in more. Fork sits further to passenger side
Is .608 not within spec? I've read that .608 to .610 is ideal for performance.I thought having a shallow step helps the fork sit closer to driver side and not the passenger?
 
.608 means nothing. You must follow the spec of whatever clutch manufacturer you are using. Everybody is different. And no. Shallower moves the fork towards the passenger.
 
.608 means nothing. You must follow the spec of whatever clutch manufacturer you are using. Everybody is different. And no. Shallower moves the fork towards the passenger.

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at the 2:30 mark jack says that when you take away flywheel material meaning you have a deeper step your fork moves further towards passenger side. Unless i'm understanding wrong.

I don't have any clutch drag. All i want is for the clutch to engage closer to the floor with disengaging around the 3/4 pedal travel (1/4 travel of free play from the top of the pedal stroke). I'm looking at the first set of pics in my original post (post#1) and noticing that the fork is practically centered in the fork hole with being slightly towards the driver (slave side). All i'm asking is by looking at the second set of pictures (post#6) the clutch fork is sitting over towards the slave after shimming with a 1mm washer. Would the removal of the shim to bring my clutch fork back to more centered in the fork hole, bring my clutch engagement down towards the floor? As where the fork sits right now, I'm maxed out on pedal travel and don't have enough free top play in the pedal. I have tried adjusting the top stopper all the way out to raise pedal height and tried turning the master cylinder adjustment to bring the engagement down the pedal travel but i have to adjust it to the point where not enough fluid is being pushed through the clutch and the pedal travel definitely feels wrong.

If i were to get the step height machined to .610 would it not possibly just account for the fork sitting roughly where it would have been without the shim? As in i could just remove the shim?

I'm not a clutch expert so any descriptive direction would help a ton.
 
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