Well, perhaps I posted too soon. Now that I have put some miles on the new clutch setup, I am finding that things often feel exactly as they did before. The intensity comes and goes, but it’s always the same sort of vibration or roughness and always in the same 1600-2000 rpm range.

Seems like I have ruled out a clutch or flywheel problem at this point. All the transmission bearings felt great. Motor mounts are new but not the “steady rest.” Also, the exhaust pipe is very close to the frame where it passes through on the passenger side. I’m hoping it’s just some kind of engine-to-frame contact.

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive

Definitely. I can’t perceive the engine revving any more slowly either. It just feels like everything works more cohesively.

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive

That is great to hear. I’m guessing driving with a steel or cast iron flywheel Is more of a pleasure than the aluminum one. I’ve always liked a heavier flywheel on the street..

56 Vic, B'Ville 200 MPH Club Member, So Cal.

I ended up sourcing clutch parts from Van Pelt and using a steel flywheel I had from a 223. I had them balanced and am pleased to report clutch engagement and drivetrain are both silky smooth!

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive

Correction: my input shaft is 1" diameter.  I put a caliper on it to be sure.  Looks like Vanpelt Sales might be my source.

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive

Not sure on the Ford collars diameter but for the, Muncie, BW T-10, Richmond, and Tex Racing transmissions I’ve used I have collected TO bearings with 3 depths. It has depended on which style pressure plate is used to determine the correct geometry. I have also added washers behind the screw-in pivot ball to adjust them. 

56 Vic, B'Ville 200 MPH Club Member, So Cal.

If a 10" clutch worked before then it will probably work again.  Diameter is only one variable and a lot more goes into a clutch.  11" probably is "safer" in terms of working correctly for the application.

For a 1 1/16" x 10 spline and 11" diameter, 275 clutch kits:
https://www.summitracing.com/search/part-type/clutch-kits/disc-diameter-in/11-000-in/input-spline-quantity/10/input-shaft-diameter/1-063-in?SortBy=Default&SortOrder=Ascending
You will need to ensure that it will mount to the flywheel, or have the holes drilled and tapped.

I had troubles with a diaphragm clutch in my truck.  I think the problem was due to the pressure plate being thinner, throwing the geometry of the clutch fork to throwout bearing interaction out of whack, which resulted in bearing collars wearing prematurely.  With no easy way to try to correct that geometry, I simply converted to a hydraulic throwout bearing setup.
I don't know that it was the problem and it may not mean anything for yours, being a car, which uses a different fork and TO bearing arrangement.


Lawrenceville, GA

I have a steel flywheel from a 223. It also has a 10” clutch and pressure plate, but came off a truck. This will work with a y-block too, right?

Any concerns using a 10” clutch with a 312? I’m not sure I can use the 11” because my transmission input shaft is 1-1/16” diameter.

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive

Years ago I purchased a flywheel from Mummert. It came drilled for the standard (long style) clutch and the diaphragm (Mustang) clutch. Not sure what's available now but a throwout bearing and hub was available too.  Good luck...............

64F100 57FAIRLANE500

Phil, mine is the same as yours with the spiral groove in the bearing retainer. The gasket is very thin and I suspect the surfaces weren’t perfectly clean when it was assembled last.

Good news! With the clutch off I believe the vibration is gone. That is to say, there is no noteworthy change in vibration as I move from 1000rpm up to 2000rpm. The clutch disc is pretty worn anyway so I’ll do the full job, get the assembly balanced, and get back to driving.

I am thinking I need a new flywheel though. Here are some pics of the Schiefer unit on the car. There are 3 hot-spotted areas evenly spaced. The friction surface is not perfectly flat either, with a lip at the perimeter. Can’t tell what it’s made of, but it looks almost like brass.

This is a 10” clutch with 10 splines. Any leads on a good source for the flywheel and clutch kit? Opinions on going to diaphragm-style if available?

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive