273 to 340 swap in 64 cuda auto advise needed

guido said

In dead from shoveling snow for 7 hours, so if I'm scatter-brained im sorry. I keep hearing there.are early model 340 driverside manifolds that will fit on my 64 cuda with power steering. I have a picture of one installed but no definite year or p/n.yet I hate to be buying 340 manifolds willy nilly. I'm afraid I'd end up with a collection. I am convinced someone here knows
It may just take a while. I can't be the 1st one to do this
I didn't know the 273 intake will bolt up. It's good to know. It will simplify linkages if I go that way.
I do have to say though there are a lot of great people here on this site

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If your 273 is a '64-'65 model, the intake will NOT bolt up to the 340. Besides the port mismatch, the intake bolt angle is different on the early 273 than on '66 and later smallblocks.
Since your 340 is a '71, that simplifies things quite a bit from my earlier post. The 273 torque convertor should bolt up with just the crank adapter bushing.
Did your 340 come with an intake or exhaust manifolds? The fit of the 340 exhaust manifolds is the same, early or late- as long as they are A BODY manifolds. Anything else is at your own risk. Just like the pic in my previous post, 340duster340 has early 340 manifolds fitted with the Borgeson box. Drop him a PM if you need particulars. MUCH better breathing than the 273 exhausts.