opos

I've touched on this subject before but am still trying to understand a few things..please excuse an old man (80 yesteday) for not being too quick on the uptake.

I have my nice '73 Cutlass Supreme...super clean and solid car...daily driver. It has a 350 with a turbo 350 and about 72K original miles. I've thought of having a frined (good solid mechanic)do a swap with an Olds 455. I ran across a complete and running (never rebuilt before) 73 455 for $450...Figured it might be a nice core/base engine for a swap out being it's the same year..

My buddy and another guy that is fairly sharp both indicated the 73 455 is not the engine to use for a swap even with it being the same year...they indicated an older year model 455 with moderate machine work would be a very strong motor while the 73 big block would gain me some torque but very little h/p and it was not an engine that lent itself to being "built",
Looking for a moderate build...not a touchy engine that would give me both increased h/p and torque...would plan to swap the turbo 350 out and change the rear end gears....

The one guy said why not just build a moderate 383 and drop that in? Said I'd get near 450hp with a small engine and the 450hp build is moderate and would give me a nice increase over the 350 18o hp I now have..

Looking for some chatter on the ideas...being older I got some money stashed and guys that will work with me to do the things I can't....still not ready to sit down with reruns of MASH>

Thanks
opos

olds 307 and 403

The main problems with the 73 455 are the huge dish pistons, which would get replaced with a rebuild anyways and the J heads. The J heads need a lot of porting on the exhaust side to flow. A set Procomp heads, higher compression pistons and a bigger cam goes along way. Your 350 is a gooď motor also uses big chamber heads that just need a bowl hog under the exhaust valve to flow as well early 350 heads. Combine the 8 to 1 compression and tiny cam makes your 350 handicapped. Speaking of strokers, with a steel crank 3.875" stroker package for your stock Olds 350 would give you 414 cubic inches from Cutlassefi (Mark Remmel). Mark could pick you a cam and pistons to work towards your goals and octane usage. Add bigger intake valves and a bowl hog under both valves on your 350's #8 heads or Procomp heads with a Performer RPM intake. Add Thornton 350 manifolds and 2.5" dual exhaust for easy maintenance.

joe_padavano

The first thing I learned is to ignore idiots whose only response to any question it to hit it with a Chevy hammer.

If you are going to rebuild the motor, a 73 455 is just as good a starting point as any other. You presumably are going to replace the pistons anyway. Buy the ones with the CR you want. Same thing with the cam. The J heads are not the best, but again, what do you plan to do with the car? If this is a street cruiser that will rarely exceed 4000 RPM, you'll never be able to tell the difference in the head castings. Alternately, modern aluminum heads are better than any OEM cast iron head, and by the time you have iron heads done, you'll have about the same amount of money in them as you would just buying aluminum ones.

svnt442

I rebuilt a 73 455 about 25 years ago and had a ton of fun with it in a 70 Cutlass. I went .030 over with L2323F30 pistons, an Erson JB100 cam, Performer intake and an Edelbrock 1407 carb. Nothing special, but it was a tire fryer.
I used a B&M holeshot 2500 stall torque converter with a TH400 trans and even with the 2.56 gears it wasn't slow.
The heads just had a clean up rebuild on them, no porting or anything and they worked well enough for me.

64Rocket

As svnt442 said it is an super easy way to go.
You can use better cast pistons from today's crop of pistons.
The "J" heads will work fine for what you want to do. An aftermarket intake will be a better choice than the cast iron one you have.
A nice street cam will make good low end torque to get that car moving.

Gene

wr1970

This^^^^^^^ enough said.

olds 307 and 403

There you go but maybe use the Qjet off the 455 if you have it. Many have issues with Edelbrock carb. Even a bowl hog under the valves and a good valve job with springs to match the cam you choose will make a difference. That and the high compression cast replacement pistons are available for your 455 to bump from 8 to 1 to over 9 to 1 compression as said.