403 olds in a 1981 cutlass
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The 403 would be allot less work than the 455. The 403 is the same physical size as a 307 so you can use the same motor mounts, all brackets and accessories will bolt up with no modification. You can use the same exhaust that came off the 307 or sbo headers are available for that body style just depends on how much you want to spend. Good Luck!
Should be less work. The 403 is externally identical to the 307 so it's just a matter of swapping some parts over and dropping it in. This is all assuming you have a 307.
This is for a 3.8 to Olds swap, but most of the info is the same. http://www.robertpowersmotorsports.com/G-bodyV6-V8.html
Do you know what engine was originally in the car? You will need a different trans but it does not have to be a 400. It just needs to have the BOP bolt pattern. That could be a 350, 400, 200-4R, or 200.
Do you know what engine was originally in the car? You will need a different trans but it does not have to be a 400. It just needs to have the BOP bolt pattern. That could be a 350, 400, 200-4R, or 200.
rccktmn2 said:
Why do you say that? :?
A 455 requires no more work to install than a 403 would.
They're pretty much the same thing, with the exception of the 455 being a tad wider/taller due to the added deck height.
Blake442 said:
IMO it would be easier not neccessarily less work. Considering the 403 is the same dimensions as the 307 everything will bolt up without any modifications, the 455 would require 455 brackets and then you would have to move some accessories around, that is if your keeping the accessories. Then the exhaust from the 307 would bolt up to the 403 with no problems, the 455 would require either the exhaust manifolds from a 455 or headers which are more expensive in a g body than regular sbo headers for a g body, then you have single or dual exhaust, 307 will bolt right up, 455 would require either custom exhaust work or a dual hump crossmember and dual exhaust. Then you run into the right intake to put on, if you do a tall aftermarket alluminum you have to get a different hood, if you do a short aluminum intake you can do a stock hood, or you could go factory. I guess I should have said more things to consider not neccessarily more work, installing an engine is installing an engine, there all about the same amount of work.
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