george@BWR

I have a 1972 Oldsmobile Cutlass Supreme with a Rocket 350 and a Muncie transmission with a 4 speed Hurst shifter. After driving the car long enough to get it fully warmed up I get a chatter in the clutch only when in reverse. Does anyone know what may cause this and how to fix it. I have had a new clutch kit installed but that did not help.

Oldsmaniac

from time to time the flywheel needs to be resurfaced.

Sugar Bear

Does the car have a limited slip differential? Backing up in a nearly straight line? Is this occurring while the clutch is fully engaged OR when it is being engaged?

droldsmorland

Not resurfacing a flywheel is like replacing brake pads and using the old worn rotor surface. Its a gamble and never recommended.
Check out this info:

https://www.google.com/search?client...5NoPiO2Q4Ac_28

http://farmmachinerydigest.com/groun...ng-a-flywheel/

george@BWR

The car does not have limited slip. It happens backing in a straight line when clutch is being engaged

Sugar Bear

Rules out limited slip clutch chatter. Was the flywheel resurfaced during the clutch replacement? Motor mounts good, particularly the right side?

Cosmic Charlie

I read somewhere that the M20 4 Speed with the 3.08 rear end was **** to reverse chatter while engaging ...
My does - so I work around it with decent results (just a little extra slip to get the car moving then back off and then fully engage +-) lol your results may vary

george@BWR

Thanks! Does this ever happen in first gear? Seems it only happens in reverse for me.

Cosmic Charlie

Just reverse for me

fleming442

I'll throw my 2 cent in. I'm going with a high gear ratio problem and as @Cosmic Charlie mentions, it needs more rpm and slip. I heard somewhere that reverse is similar in ratio to 2nd, but I have never looked it up nor counted teeth.
I had that problem with a Spec stage 3 sintered bronze disc and a Centerforce dual friction. I have not experienced it since switching to a McLeod twin disc RST all organic..... just some things to chew on.

VC455

Here's what I have on Muncie reverse ratios. Reverse is a bit steeper than first gear.

1963-65:
M-20 Reverse ratio 2.64
M-21, 22 Rev ratio 2.27

1966 on:
M-20 Reverse ratio 2.59
M-21,22 no change from 63-65