What would you prefer

[Evan11]

455!

 

[mjscutlass]

Back 20 years ago I would have said 455 all day. Then the reliability comes into play when im on the high way. I'm just really torn. My first motor change ever was 403 in place of 307... I think ls is best..

 

[1Bad4558]

It all depends on what it is gonna be used for. I would choose the 455 for a good street car and occasional cruise nights but if you wanna drive it daily I would go with the ls.

 

[Alerch]

Big block for sure! Im putting a warmed over 1967 400 in mine 😀

 

[olds307 and 403]

Depends on the condition of the core motors. What year is the 455? You can pull 20 mpg imperial out of a mild 403, I did.

 

[mjscutlass]

76 455 all stock. 403 a little warmed

 

[DoubleV]

Do you know all that's involved in an LS swap? Do you already have all the parts to do that swap including electric fuel pump if you want to keep EFI? Are you prepared for all the 'little things' you gotta do to get everything in and working correctly? If you have all the parts ( or are prepared to go out and buy them all ) and know exactly what you're doing, an LS could be a good choice. If you want dead simple, your warmed 403 is the cheapest and easiest option. The 455 a close second.

 

[mjscutlass]

So I thought I found an all aluminum ls and trans out of a Camaro. I drove 90 miles to look at this motor and its was a 3800 v6.He was asking 1500$ for it... I was so pissed.. I think I'll go with the 403.

 

[1evilregal]

So I thought I found an all aluminum ls and trans out of a Camaro. I drove 90 miles to look at this motor and its was a 3800 v6.He was asking 1500$ for it... I was so pissed.. I think I'll go with the 403.

that would've been my vote... easy to make look stock, easy changeover with little down time, and any tricks to help in additional power have been covered and are tried and true...

 

[mjscutlass]

I scored today!!! Was at the local pullapart and there was a 65 cutlass with a 425 for 180$ owe yea baby