Originally Posted by Hellcat41
Now do I have to get a aftermarket block or using an old 350 work? I might be able to get my hands on a cheap 454 but then that's more fabrication to mount it.
At the less than 550 HP level a stock 4-bolt main 350 block will be plenty strong enough, even a stock 2-bolt 350 block will be fine at 400 HP...no need for an aftermarket block.
454 is nice, big cubes make big power easier, but might open up a cooling nightmare in the narrow '41 nose, require an expensive radiator and expensive custom headers. Big block performance parts are also more expensive than small block.