C1 side engine mount
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C1 side engine mount
I have a 62 vette with approx. 400 HP, 406 CI SB. Clutch chatter has been a constant issue. The clutch was new with the engine install and frame off restoration. I have tightened down the stock front rubber engine mounts as far as they can go and maintain fan shroud clearance. I purchased an engine side mount kit, however, during the trial fit I quickly noted the stock steering arm would strike the mount bracket, on the drivers side, on a left turn. Although I would much prefer side mounts, there just does not seem to be space available, for a side mount, with the stock steering. I believe I have read, on an earlier post, where someone had made the stock 62 front mount solid, no rubber spacers, however, I no longer see that thread. Any suggestions would be appreciated. The resolution needs to have dependability as this vette is driven quite a lot.
The chatter is at partial engagement. Cam is pretty loppy. It is hard to tell with 360 degree bellhousing, have My6 transmission, however, there does not appear to be oil inside the bellhousing. The flywheel was resurfaced during engine replacement, also new clutch.
The chatter is at partial engagement. Cam is pretty loppy. It is hard to tell with 360 degree bellhousing, have My6 transmission, however, there does not appear to be oil inside the bellhousing. The flywheel was resurfaced during engine replacement, also new clutch.
Last edited by corvette62; Sep 19, 2011 at 09:19 AM. Reason: Additional information
Race Director
Joined: Nov 2000
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From: Beverly Hills (Pine Ridge) Florida
I guess my first question is why do you think tightening down the stock front mounts (or changing to side mounts) is an answer for your clutch chatter. I run a 350 (dual quad, headers, etc.) with the front mounts, and have drag raced it (I typically came off the line at 2000 rpm when I was running 4.11 rear end), with no chatter ever (11" clutch disc) with the stock front mounts.
First area I would look for to fix a chattering clutch is the disc and potential oil contamination.
Good luck,
Plasticman
First area I would look for to fix a chattering clutch is the disc and potential oil contamination.
Good luck,
Plasticman
Last edited by Plasticman; Sep 16, 2011 at 11:10 PM.
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Don't think your supposed to crank down the front mounts. They're designed for about 25 ft lbs I think? mashing them down will only squish the rubber and put the whole drive train out of alignment. You should get some polypropylene (?) new mount spacers that flex less and are stronger. If you're having too much engine twist, you might try a turn buckle cable/chain on the drivers side. 
Drifting
Joined: Feb 2006
Posts: 1,840
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From: Towaco NJ
I have a 62 vette with approx. 400 HP, 406 CI SB. Clutch chatter has been a constant issue. The clutch was new with the engine install and frame off restoration. I have tightened down the stock front rubber engine mounts as far as they can go and maintain fan shroud clearance. I purchased an engine side mount kit, however, during the trial fit I quickly noted the stock steering arm would strike the mount bracket, on the drivers side, on a left turn. Although I would much prefer side mounts, there just does not seem to be space available, for a side mount, with the stock steering. I believe I have read, on an earlier post, where someone had made the stock 62 front mount solid, no rubber spacers, however, I no longer see that thread. Any suggestions would be appreciated. The resolution needs to have dependability as this vette is driven quite a lot.
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I use 1/2 solid aluminum mounts, just on the underneath side, the top halves are stock rubber. It keeps normal running vibrations down, yet keeps torque compression of the mounts from happening.
But, as others noted, that isn't your clutch chatter problem. I am running a 427 CI SB that has 400 RW ft-lb Tq at 1500 RPM, and I don't have chatter.
Doug
But, as others noted, that isn't your clutch chatter problem. I am running a 427 CI SB that has 400 RW ft-lb Tq at 1500 RPM, and I don't have chatter.
Doug
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I have run solid aluminum mounts in my car for years. No down side for doing it. And I race it regularly and drive it on the street. If you want reliability and the ability to beat on it with a bunch of HP, just ask. Basically cut/machine the solid material to basic shape of the upper rubber, fab up a lower piece to lock in the upper. You should be able to make it up to 7/16" less in height for more carb/manifold clearance if you want. If you do not want to have water pump leaking problems to the mount/block, I have cure for that also. We race hundreds of runs, launching at 6000 rpms, with zero problems.
Drifting
Joined: Feb 2006
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From: Towaco NJ
Front mount modification. Weld legs to good stock mount. Legs get attached to what we used to call, the 55 Chevy mount holes. Make sure the fit has no slop in it. Chrome is optional.
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Thanks for the info and photos. I am impressed with your approach and plan to follow through. Do you have drawings or would you be interested in supplying unfinished parts? If so please list a contact. If necessary I can develop my own from the original 327 on an engine stand in my shop.
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Melting Slicks
Joined: May 2000
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From: Chuckanut WA
Don't think your supposed to crank down the front mounts. They're designed for about 25 ft lbs I think? mashing them down will only squish the rubber and put the whole drive train out of alignment. You should get some polypropylene (?) new mount spacers that flex less and are stronger. If you're having too much engine twist, you might try a turn buckle cable/chain on the drivers side.
My rubber mounts have a steel spacer sleeve which limits the compression to a predetermined spec. If yours doesn't have these perhaps they are missing. I tighten them down till they come up against the spacer and that gives them the proper amount of preload.
