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4 speed removal for new clutch-any good tips


Senior Member
Oct 24, 2000
81 4 speed
I have just ordered a new clutch after eventually finding a good UK supplier with the parts I wanted in stock and I should receive it early next week.

Any good tips on the removal and refitting of the gearbox ?

I have access to a lift to do the job.

The clutch is a QuarterMaster twin plate button type and requires the original flywheel to be replaced with an auto trans flexplate. The guy asked me if the engine was internally or externally balanced. I assumed all small block chevy engines were externally balanced with the damper on the crank snout.

Can anyone enlighten me on this subject ??

I am also interested if anyone knows of a supplier that sells uprated rose joint clutch linkages as I would like to improve on the original for a smoother action.

As always I look forword to your comments

Have you considered going to the Quartermaster Hydraulic release bearing assembly and converting it all over to a hydraulic system? That would do away with the linkage all together.

It is a beautiful piece. Racers have been using them for years. It bolts on the trans where the release bearing goes, but has a hydraulic slave built in. You end up with nothing but hydraulic lines coming out of the bell housing instead of linkage.

The problem is, I have not figured out what type of master cylinder to run yet and how to hook that up.

I guess I will post that question soon.

I could have sworn I drove an 81 Corvette back in 1986 that had a fully hydraulic clutch. I have been checking the local parts houses and they say they do not make a hydraulic master cylinder for the C3.
external vs internal balance

400 and 383 (350 block w/ 400 crank) small blocks are EXTERNALLY balanced with both a different harmonic balancer/damper and different flexplate ... both hb & fp designed for sb 400 crank. As far as I know, all OTHER small blocks (i.e. 265, 283, 302, 327, 350) are INTERNALLY balanced. DO NOT OVERLOOK THIS ... it's NOT a mere detail. If you're running a 400 crank (3.75"stroke) or a stroker-crank "Based" on a 400 crank ... then you must use a 400 type hb and fp. 400 cranks' counterweights are DIFFERENT than other sb cranks ... thus they are EXTERNALLY balanced. Hope this helps.

I did price a hydraulic release bearing but firstly they were expensive and secondly I figured that fixing up a slave cylinder and pedle in the confined space available would be to much like hard work. I was impressed by the quality of the QuarterMaster kit when I saw it, expensive but looks good.


Strangely my engine is a combination of a 68 327 block and what I assume to be a 350 crank as it has 3.48 stroke and the piston do come right to the top of the bore. Would you recommend balancing the flexplate before installation ?
re-balance ... probably not

If you will be running motor with same rods, same pistons, same crank ... and all had been running smoothly ... I see no need for balancing a new or used 350 flexplate. If it's a used FP, I would inspect FP closely (maybe have it magged or zyloed at your machine shop) for cracks. A standard, new flexplate for a 350 can be had in USA for under $30 ... race-approved ones under $60. Before you buy/order a flexplate, count the teeth on your flywheel first ... some have 153 ... some have 168 ... yours probably has 168t. BTW, all Chevy V8's, sb & BB, come with a balancer/damper on crank snout. You might also check your balancer to see if the rubber in it has gone mushy from age, heat & solvents. The outer ring can slip; causing timing mark to be improperly indexed ... even worse, the ring could fly off and wreak havoc. New, standard balancers under $60 ... race-approved can reach $200. Again, if all things remain the same ... I don't recognize a need to balance a flexplate. Just get a FP for a 350 (internal balance) and with same number of starter ring gear teeth as is on your present flywheel. However, since you are bolting a clutch assembly to a flexplate, I would check with Quartermaster to see if they recommend balancing the flexplate ... I doubt if they will ... also ask if their clutch bolts to flexplate size (153t or 168t) you've selected ... I'd be interested to hear what you find out.

Nothing will be changed inside the engine, all that has already been done and the motor revs smooth and hard. I have ordered a full kit which includes a 168 tooth race flexplate, a release bearing and an ARP bolt set. The whole new assembly only weighs about 16lb.

It will be interesting to see how it works out at the strip. Last summer with the old engine the car consistantly ran the 60` below 2 seconds. The first time out this year with the new set-up the clutch got shredded in the first race but even with a 2.8 60` it ran 13.8@104 so I`m hoping with the clutch sorted to run in the low 13`s


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