I have a 1981 cutlass with a V8 260 engine. I was wondering should I replace with a olds 350 or 455? I know I am going to have to replace the transmission. Without having to make a lot of modifications, will a olds 455 drop in engine bay without modifications and can I run ac? Thanks
Olds 260 replacement
- Thread starter DP in OC
- Start date
To choose between them, you'll be miles and smiles ahead if you put something in that FITS with virtually no modifications, such as the 350. Looks the same dimensionally as the 260, yet is way better on performance.
As far as build, you can do anything your heart and wallet desires. Issue with BBO in the 78-88 Cutlass is that there's limited room under the hood to do anything crazy like tall intakes, spacers, etc. with a 455. Unless you start cutting hood holes or buying scooped hoods, just adding to the expense.
Can you do it? Sure. But you'll need to modify some A/C brackets if you want to keep your original pulley setup, etc., with a 455, or just swap them over to a 350, for example. Put a TH350 behind it, and you're set for a great fully streetable situation.
As far as build, you can do anything your heart and wallet desires. Issue with BBO in the 78-88 Cutlass is that there's limited room under the hood to do anything crazy like tall intakes, spacers, etc. with a 455. Unless you start cutting hood holes or buying scooped hoods, just adding to the expense.
Can you do it? Sure. But you'll need to modify some A/C brackets if you want to keep your original pulley setup, etc., with a 455, or just swap them over to a 350, for example. Put a TH350 behind it, and you're set for a great fully streetable situation.
I did back in early eighties. Last one i did was 78 or 79 cutlass. Pulled the 260 and trans, and replaced with 350 and th350 out of a 73 Custom Cruiser. Everything was basically plug and play.
Visually looks the same. Nothing needed changed. Car was console shift so cable hooked and up fine, drive shaft yokes were the same, crossmember the same.
Visually looks the same. Nothing needed changed. Car was console shift so cable hooked and up fine, drive shaft yokes were the same, crossmember the same.
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The A/C brackets will not fit on the BB 400 through 455. Also a factory air cleaner will have issues. Either an Olds 350 or 403 with a short tail TH350 will bolt right in. A 2004R requires frame extensions on a 81, I believe.
In the early eighties that was the very first engine swap I did. 79 Cutlass with the 260 to a Rocket 350/ th350. Everything just fell right into place like it was ment to be there.
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