Swapping in 455 in place of a 350 in 70 Cutlass. Familiar with the motor mount info--using the 350 motor mounts with 350 frame mounts.

Question: Are there accessory bracket issues? Non A/C car. I have all the 350 non A/C brackets--Power Steering, Alternator, Pulleys. Will these all work or do I need to get 455 brackets?

Question: What about the radiator? Currently 3 core with automatic transmission. I will be swapping in a Muncie M20. Can I just leave the automatic cooling line ports open? Will the 3 core be enough for a 500 HP/500 TQ motor that is never going to the strip. 3.42 gears. Stop light to stop light freeway cruiser car.

Thank you.
David DeCan

 

I can answer the accessory bracket question. Your 350 brackets will work just fine on the 455

John

 

Brackets are the same...multiple holes for the Alt bracket mounting locations. The P/S bracket is the same as the lower part of the block are the same. Don't forget the spacer behind the lower bracket on the side of the block just above the pan rail, or the P/S pulley will be cocked a bit and it will drive you nuts trying to figure out why.
The cooling ports are fine to not use, but I would still plug them to keep crap out of there.
As far as holding 500 HP....maybe. It would be better to upgrade it IMHO just to be on the safe side.