for years i have worked on small blocks.. when you needed a starter you just said i need a starter, thats it.. i have a 82 pace car with the carb 305..its locked, to save time i bought a 84 305 out of a truck.. when i went to mount the starter it wouldn't bolt up.. i have both engines on stands, the camaro motor has a smaller flywheel/ flex plate.. its like 12 inches ( off the top of my head) and the truck motor has like a 14 inch wheel... anyone know what the deal was? i never knew there were different size flywheels? since the 305 is internally balanced does it even make a difference? is there a benefit to one or the other?
thanks for replies
Roy

 

cars usually use a 153 tooth flexplate while trucks often
have a 168 tooth flexplate.with equal starter motors,
the 168tooth will give a little more cranking torque
because of the deeper ratio.

 

Regardless of engine type , crank balance style , etc
you purchase GM starter by it's mounting bolt configuration

Straight bolt pattern = 153 tooth
Staggered bolt pattern = 168 tooth.
Most aftermarket "mini" starters have 4 bolt holes to suit both size flexplates