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Rowing some gears


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1320 has all my passes on video, but he has a lot of other stuff to get done first lol.

 

It was doing consistent 1.61-1.65 , and yes, it would just blow the tires off above that. However, it might be a completely different story with a better prepped track. The track manager wasn't there, so they didnt prep it, BUT I didn't get the boot for no cage - which i would have- had he been there. So it all worked out i suppose.

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Describe your clutch release technique? Just got in from garage getting new clutch buttoned up. All that is left is bleeding the hydraulics tomorrow night. My old flywheel was warped like a funnel (that's an axaggeration but you get the picture), high on the outside and low near the bolts. New clutch disc is 8mm thick, the old one was 5mm thick (don't know where they start). Gonna be several weeks of break-in before posting new numbers trying to match your times. I got a long way to go toward getting off the lights like you.

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I stage, and then put the car in gear, and bring the clutch to right where it starts to engage, and when the tree turns, I release the clutch very quickly - not just a dump. I'd say aim for 1 sec until full engagement. Thats where I'm at right now, but it definitely has room for improvement.

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Clutch is back together, car is running. Engages smoothly, but I may still be having trouble getting adequate disengagement. I can get the rear wheels stay still when car is on jacks and in-gear, but there is very little safety margin and it takes very little lifting of my clutch pedal to get the tires rotating. I have the adjuster rod lengthened all the way absolutely as far as it can go. I bled like a mother using mity vac and speed bleeders. Pedal feels good and firm from top to bottom. I have an inspection hole in my bellhousing and I can see the throwout bearing move just as soon as my buddy touches the clutch pedal, but while I can see the clutch disc "relax" some, I cant see any airgap between either it and the flywheel or between the disc and the pressure plate. However, I'm only getting about an inch of stroke of the adjuster rod (I put a zip tie on it and watched to see how much it moves. I have a 7/8" master cyl. I have all the adjustment bumpers all adjusted for maximum pedal throw. How much have you got your adjuster rod adjusted out? I also noticed that the hole in the pedal that the clevis pin rides in is sloted and elongated. Should that hole be round-if so, I may move it down a 1/4 inch or so to get more stroke of the piston? If so, I need to pull my pedal and have that hole welded and re-drilled, if so then I may even move the hole down a quarter inch or so to get some additional stroke. Gonna order some more hydraulic fluid (ATE Super Blue) and keep bleeding hoping that there is still a little air somewhere.

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Clutch is back together, car is running. Engages smoothly, but I may still be having trouble getting adequate disengagement. I can get the rear wheels stay still when car is on jacks and in-gear, but there is very little safety margin and it takes very little lifting of my clutch pedal to get the tires rotating. I have the adjuster rod lengthened all the way absolutely as far as it can go. I bled like a mother using mity vac and speed bleeders. Pedal feels good and firm from top to bottom. I have an inspection hole in my bellhousing and I can see the throwout bearing move just as soon as my buddy touches the clutch pedal, but while I can see the clutch disc "relax" some, I cant see any airgap between either it and the flywheel or between the disc and the pressure plate. However, I'm only getting about an inch of stroke of the adjuster rod (I put a zip tie on it and watched to see how much it moves. I have a 7/8" master cyl. I have all the adjustment bumpers all adjusted for maximum pedal throw. How much have you got your adjuster rod adjusted out? I also noticed that the hole in the pedal that the clevis pin rides in is sloted and elongated. Should that hole be round-if so, I may move it down a 1/4 inch or so to get more stroke of the piston? If so, I need to pull my pedal and have that hole welded and re-drilled, if so then I may even move the hole down a quarter inch or so to get some additional stroke. Gonna order some more hydraulic fluid (ATE Super Blue) and keep bleeding hoping that there is still a little air somewhere.

 

Ooops. double post - sorry.

Edited by RebekahsZ
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The true test of disengagement should be this:

 

Put the car on the ground, then start it in first gear with the clutch pedal pressed. Rev the engine to 4-5K, and if the car doesn't move, you're in good shape. I found that my clutch was a litlle more friendly to drive the closer to not being able to disengage that it was (shorter on the pushrod). However, to gain the abilitly to shift at high rpm's, you have to lengthen the pushrod to facilitate more separation between the clutch/fw/pp assy. .

 

And yes on the hole for the clevis pin. I took my pedal assy out, and welded the holes shut on both that and the brake pedal, then re-drilled them where they should have been. Takes some of the "no pedal at the top" feel out of them. I would also strongly suggest taking some material out of the "pedal box" ... if that's what its called... so you can adjust the MC easily. I can take a pic of this if you'd like.

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The true test of disengagement should be this:

 

Put the car on the ground, then start it in first gear with the clutch pedal pressed. Rev the engine to 4-5K, and if the car doesn't move, you're in good shape. I found that my clutch was a litlle more friendly to drive the closer to not being able to disengage that it was (shorter on the pushrod). However, to gain the abilitly to shift at high rpm's, you have to lengthen the pushrod to facilitate more separation between the clutch/fw/pp assy. .

 

And yes on the hole for the clevis pin. I took my pedal assy out, and welded the holes shut on both that and the brake pedal, then re-drilled them where they should have been. Takes some of the "no pedal at the top" feel out of them. I would also strongly suggest taking some material out of the "pedal box" ... if that's what its called... so you can adjust the MC easily. I can take a pic of this if you'd like.

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Subtle teasing me about the double post? Haha! Anyway, thanks. I cut down a 7mm open end wrench and adjusting is a breeze. I'm just surprised that I need ALL of the pushrod. I guess as the disc wears, I'll wont need as much pedal? I'll try the rev up to 4500 and see if it moves. I wonder if failure to disengage could have played a role in the quick failure of my stock clutch. I've tried master cylinders from 3/4, 7/8, and 1". The 3/4 and the 7/8 are about the same in terms of available pedal stroke. The 1" needed lots less, but it never really felt right (no modulation of pedal-kind of off or on). It was with the 1" that my clutch failed to disengage at high rpm, so I'm not sure that a bigger bore is the way to go. More rain tomorrow, so maybe Wednesday I'll start laying down some miles on this clutch.

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I've never personally done it, but they say you can over extend the slave if you adjust your master cylinder out too far(I.e. too much movement). RebekahsZ I wouldn't worry a whole lot about engagement until you get it broken in, the feel and engagement points will change a lot during the first 500 miles. I also found that if I shortened the stroke(I.e. less master cylinder movement) it became easy to shift gears at low rpms, but like Sunny said, you have to have the extra stoke for the high RPM shifts. If you get used to it you can smooth up your shifts when you are driving normally by not pushing the pedal all the way down, just push it 3/4 or so. Or at least thats how it seemed for me. On my car when I would do the pedal to the floor rev to redline test, it wouldn't roll forwards when the revs were climbing, but as soon as I let off, it would inch forwards some. Never was able to get rid of that. I will agree that 2nd gear launches have to murder a clutch.

 

What springs/struts are you running Sunny? I know some guys are pulling 1.4x sixties on some skinny slicks, granted they probably have a lot more power, but you are blowing the tires off. I assume your setup is relatively stiff, which I would think hurts your 60ft times. I know ive read people cut 1.4x on stock springs and parts store struts.

 

-Will

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Yeah, I tried a couple different settings on the shocks, but it didnt really matter as the track just plain wouldn't hold it. even the big tire cars were having issues. I can't wait to go somewhere that will have "pull your shoes off" prep.

Edited by SUNNY Z
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The true test of disengagement should be this:

 

Put the car on the ground, then start it in first gear with the clutch pedal pressed. Rev the engine to 4-5K, and if the car doesn't move, you're in good shape. I found that my clutch was a litlle more friendly to drive the closer to not being able to disengage that it was (shorter on the pushrod). However, to gain the abilitly to shift at high rpm's, you have to lengthen the pushrod to facilitate more separation between the clutch/fw/pp assy. .

 

And yes on the hole for the clevis pin. I took my pedal assy out, and welded the holes shut on both that and the brake pedal, then re-drilled them where they should have been. Takes some of the "no pedal at the top" feel out of them. I would also strongly suggest taking some material out of the "pedal box" ... if that's what its called... so you can adjust the MC easily. I can take a pic of this if you'd like.

 

Id like to see some pics. All the better to help me down the road with my build. Been watching Keiths thread hoping for a fix. BTW impressive vid pulling on that zo6 :).

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Id like to see some pics. All the better to help me down the road with my build. Been watching Keiths thread hoping for a fix. BTW impressive vid pulling on that zo6 :).

 

Ok, I'll get some up. Hopefully I can get some of the dragstrip passes up soon as well. That might take some prodding for my buddy haha.

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