what flexplate for 290 and M11?

I'm pretty sure the M-35 flexplate is smaller in diameter than the V-8 flexplate -- 149 teeth if from a 196, 153 if from a 232.  If it were the right diameter (how many teeth on a V-8 ring gear?) it could be match balanced to a 290 flywheel/flexplate. Remember, the sixes are all internally balanced and use a "neutral balance" flywheel/flexplate.

The bell bolts up differently to the trans, six bolts in a circle on the M-35, the M-11 uses just four bolts in a rectangular pattern. 

Okay, you mean the M-40 flexplate for the 290. That's what had me confused! The M-3x series was used behind sixes, the stronger M-4x was used behind the small V-8 (w/2V) and starting in 70 the sixes as well.  Externally they look the same, and both series are aluminum. I don't think any of the M-4x series were air cooled, just the M-3x (but not all), but I might be wrong.

If the torque converter bolts up it should work. The converter might work -- you'll have to slip it over the shaft and into the pump of an M-11 and find out. That or compare the shafts and converter necks (but you don't have a M-11 converter, do you?).

I think the 290 would have originally had the M44, which uses six converter bolts. The M11 has four converter studs. They won't interchange without modifications.

farna wrote: Probably because the M-12 flexplate wasn't for a 290. Remember, flexplates for V-8s have to be balanced for the engine size.

Edited by Rebel Machine - Aug/21/2012 at 10:29pm

Either the M-11 or M-12 was used with the 290/4V in the Americans also, but only with the 4V.  I think your point is that the M-11/12 flexplate could be for a 290 -- and you are correct! I didn't think to point that out in the previous post, it needed to be done, thanks! Jim can order a 290 M-11/12 flexplate from one of the AMC vendors, most likely.