Can you put a Gen1 flywheel on a Gen3 engine? The answer is no. But can you if you really want to? :-)
Here is why I really want to. The gen3 flywheel is 14" diameter (168 tooth), the gen 1 is 12 3/4" (153 tooth) My bell housing wont fit the 14", and changing my bell housing is not an option (will explain further down).
Also, have read that the crank flange on LSx is 0.4" closer to the block than gen 1, that means that I've got to get my flywheel off the flange that amount to engage my input shaft correctly.
So here is my plan, please let me know if I'm missing something:
-LSx motor crank flange
-(3) of these shims (gets me 0.36" of the 0.4" I need)
Competition Engineering 4047 Competition Engineering Flexplate/Flywheel Shims
-My 153 tooth gen1 flywheel re-drilled for metric / LSx bolt pattern
Seems to easy. Am I missing something?
I'm building a mid engine corvair and am using a special bellhousing / adapter from from block (LM7 - actually LM4 /alloy) to corvair diff to saginaw in that order where the back seats were.
Here is where I got my input on the hurdles. Thanks!
Engine and Transmission Swap Gen III - Car Craft Magazine