Had clutch and flywheel lined up but that fell threw. Wondering what size the stock flywheel takes. Thx joe

Joe,

Stock 400s and "smaller" got the 10.4" (10 1/2) disc. 428s and 455s got the 11". I don't believe there were any 1st gen 'birds with the 11".

Jim

2nd Mr. P-Body.

thx guys, I am getting my parts together to install my 428. I want a 11" clutch. I was going to a swap meet this weekend. Thinking of getting a used flywheel and having it turned. What is the best way to tell the difference on a 10.4 and 11" flywheel? Joe

I just measured a flywheel with the "imprint" of an 11" disc on it. The bolt circle is 12.5" (diameter). I also measured one with the 10.4" disc. Same. 12.5". I THOUGHT they were different, but apparently not.

I would recomend a Hayes or McCleod SFI-approved flywheel. About $325. Good steel and not at least 35 years old.

I "like" Ram clutches for a streeter. The McCleod "adjustable" pressure plate is awesome in a "drag" car.

FWIW

Jim

Ok, now gon'a have to measure mine next time i'm home.
By eye, the 12 has more surface area.

You can fit an 11" disk under a 10.4 pressure plate. The 11" pressure plate causes A LOT of interference with the bellhousing and floor pan getting it on. Been there, done that. Had to grind the inside of the bellhousing and a little off the top ears to clear the floor pan. Even lifted the front of engine to gain some clearance.

HTH

I tried to put an 11 inch on my 10.4 flywheel and it would not fit. The bolt circle for the 10.4 was smaller than the 11. Some flywheels have both patterns drilled and tapped into them.
Al.