Olds 403 VS 455

[CamaroAdam73]

Alright so i've been planning my 403 build for awhile now but i got an offer today i might not pass up.

I started a new job and it just so happens one of the mechanics i work with is an olds head haha, he has a 455 for sale for 300$, it's from somewhere between 71 and 74.

So here's the bottom line question, which engine should i go with??

My 403 plan was to slap a set of 350 rocket heads(64cc chamber) and a nice cam, the works. Would this end up making as much power as a mildly built 455?


Also i almost forgot, has anybody ever heard of a Cadillac 500 in a gbody? He has two of them and is willing to work a deal, but i already know it would take some leg work to make that work.

 

[Blake442]

455 all the way!

 

[dream on mcss]

Alright so i've been planning my 403 build for awhile now but i got an offer today i might not pass up.

I started a new job and it just so happens one of the mechanics i work with is an olds head haha, he has a 455 for sale for 300$, it's from somewhere between 71 and 74.

So here's the bottom line question, which engine should i go with??

My 403 plan was to slap a set of 350 rocket heads(64cc chamber) and a nice cam, the works. Would this end up making as much power as a mildly built 455?


Also i almost forgot, has anybody ever heard of a Cadillac 500 in a gbody? He has two of them and is willing to work a deal, but i already know it would take some leg work to make that work.

About the 500 caddy, ask either Mike P or dogshit. Mike P has one in an elky and dogshit has one in a cutlass.

 

[CamaroAdam73]

Thanks for the replys.

I'm probably going to buy the 455, but that cadillac is so ****ing tempting. Honestly if he says 300 for the caddy i'm just gonna have to say **** it and buy both.

 

[dogsht]

You can check out my pics for a Caddy. Also mike has a full build thread with great pics.

 

[CamaroAdam73]

The browse member index is not working right now, can you link me to his thread? I'd really like to see what this caddy 8.2's can do, and if it's worth it VS the 455.

 

[Intragration]

I love Cadillac motors, but my impression is the 500 swap is a fairly intense operation, compared to the brainless 455 swap. I don't think either is a bad way to go, but the 455 will be easier and you'll have access to shelf parts like headers, where the Cadillac is a bit more challenging this way. How quickly do you want to drive it? I gave myself 30 days from V6 car to 455. Might take a bit longer with Cadillac. But if you like torque, there is no wrong answer. 😀

 

[littlerascle59]

I've always thought the caddy 500s were slightly smaller or lighter than the Olds 455. I think I remember readin that in an old issue of hot rod mag a few years back.

 

[trocutlass63]

I've always thought the caddy 500s were slightly smaller or lighter than the Olds 455. I think I remember readin that in an old issue of hot rod mag a few years back.

A 455 Olds weighs 620 lbs and a 500 Caddy weighs 600 lbs so theres not that much difference, and by comparison a 350 Chevy weighs 575 lbs so either way you're doing good weight wise.