Do late 60's- early 70's Buick-Olds-Pontiac manual transmission flywheels interchange or did each make have their own bolt pattern and quirks? Basically interested in the "big blocks", like will a flywheel from a 400 Pontiac fit a 430 Buick? Thanks!
I do not think the flywheels interchange for more than just bolt pattern differences, balance as well.
Pontiac was pretty much interchangable from '65-'75 or '76, then they changed the size of the center hole. Buick had a few different flywheels; I think that some of their engines had some external balance on the 'wheel. Buick 400/430/455 may be the same, but the smaller engines (300/340/350) are not. Olds had at least two flywheels in the '60s/'70s as well, maybe more, and the Buick/Olds 215 V8 was all by itself.
Not the same. In fact, I believe around 1965 Pontiac and Olds made a change that kept them from interchanging from Pont to Pont or Olds to Olds. (65 and up differ from 64 back, or something like that). But, no B to O to P
The only common part I know of is the strarter motor- Pontiac and Olds can use the same piece- and that's a '65 and up block mounted model. On the '64 and below bellhousing mounted starters, I can't say if the Olds uses the same starter motor.
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