VCCA Home Forums TECHNICAL - 1945 AND NEWER 1949-1954 Upgrading to a 10 3/4" Clutch

40 some years ago someone sold me a 10 3/4" clutch and clutch housing along with a suitable flywheel to mount them. He believed that the bigger clutch was an obvious improvement. I didn't know whether to belive him, or not.
My question to you is, is there really any good reason to replace my 9 inch clutch with the bigger one on either my 1950 convertible or 4 door Sytleline Deluxe? Neither is used in any "heavy duty" application.

If you desire a clutch that requires more foot pressure to operate then go for it. If you also want the clutch to be more "grabby" then install the larger plate. If you add significant horsepower over and above stock then a clutch plate with more friction area might be a benefit.

Unless you are pulling a heavy trailer or some odd thing stay with the original clutch.

Chip and Chev Nut,
Thank you for your input. I will stay with the 9 inch clutch.

I have tried to figure out the advantages of going with the heavy duty clutch vs the standard one. All I can come up with are the following:

Advantages (Hvy Dty):

a. Longer life. But not by much.

b. Stronger pulling power before slippage of the disc.

Disadvantages:

a. More pressure needed to disengage the pressure plate owing to stronger diaphragm. This may be annoying while having to negotiate all those stop signs and stop lights.

b. During good wheel traction or binding of the rear wheels, unnecessary higher load on the other drive-line parts (u-joint, differential gears, axles, etc before "protective" slippage of the disc can occur. More apt to snap an axle, bust a tooth somewhere or bust the u-joint.

c. Slightly heavier load on rear of crankshaft and transmission input shaft. This is only when engine is not running, I suppose.

Have I got this about right, Gene?

Thanks,
Charlie

When using a 10.5 clutch and flywheel you will have to use the starter from that assembly (12 volt ). I put a 62 235 from a pickup into a 51 to replace the 216 that was shot. Had to use 9 in from original 216 for the 6 volt starter to fit.

If a car with a 9" clutch is driven properly, city or country, the disc should last at least 75,000 miles.
I have never worn out a clutch in any of my Chevrolets. We used to have bad drivers come in for a clutch job by 20,000 or less.

I don't think so, if you are using ...say a 1941 Heavy Duty clutch assembly instead of the regular 9 inch. I don't remember seeing anything about having to change the starter. When you change out the flywheel, I think the starter gear is the same.

Accordingly, while your statement may be correct as far as it goes, it may not cover all applications as inferred.

But I could be wrong. If so, I wonder if someone else will enlighten me.

Best,
Charlie

At one time, I put a heavier duty re-turn spring on the clutch arm and couldn't tell the difference...

A 51 216 fly wheel (9 in clutch) is smaller than a 62 235 (10 in clutch) only a few teeth. I was trying to use the 216 beelhousing and 10 in setup on the 235 and use org 6 volt starter! Believe me it won't work ! Had to go to the 9 in clutch and plate to stay 6 volt original equip.

Thats the same info I have come up with while researching installing a 54 235 in my 51. The 12 volt starter could be converted to 6 volt according to my rebuilder, but I see no reason to install a heavier clutch. The flwheel, f/w housing, and starter must be of the same application.