rguertin87

I have a 1971 Cutlass S with a 350 4 barrel. It has the 3 speed automatic transmission. Im looking to install a 455, the one that I am looking at has been dyno tested at 465 HP. What else would I need to change to make this work?

svnt442

Well it's a bolt in. Use the 350 mounts, get a set of headers for the 455 and drop it in. Use all of the accessory brackets, pulleys and water pump form/for the 350.
You may need to address the transmission as a TH 350 will need some beefing up to handle that much of a 455. It will last for a little while, but don't expect miracles from it.

rguertin87

thanks for the advice, already has headers so im set there. Im planning on throwing in a 200R4 eventually, but I'm curious if I can keep my rpms down... maybe... just maybe my TH 350 wont rip in half.

redoldsman

If the headers you have are on the 350, they will not work on the 455.

svnt442

get a set of headers for the 455

350 and 455 headers are not interchangeable even thought the head flanges are the same. The taller deck height of the 455 make the 350 headers hit the side of the block, the steering shaft, dump into the floorboards......many issues that won't allow them to work.

Olds64

It might last a week or so but eventually that TH350 would be toast behing a built 455.

Jamesbo

With all due respect to the Land Yacht Comadore I respectfully disagree.

Olds64

That is fine.

Do you really think someone can stay out of the throttle with a built BBO in their car? I know I couldn't. I just started my engine a few weeks ago and have less than 100 miles on it and I have already been hot rodding around in it.