389 tri-power Q.
 

Are any of the parts interchangable from the 389 to a standard gm engine? This may be a really stupid question, but I have no idea about this engine.

As far as I know only to other pontiac motors, 400ci, 421,455. They are their
owne breed ya know.

I think a 400 is just a bored out 389 and has 3.00" mains.

The 421 and 455 have 3.25" mains.

Some what they call, "Super-Duty" engines have forged cranks whereas most others have cast.

I forget if Pontiac ever ran cast ARMA-STEEL rods or not??

Not much help..

pdq67