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Motor Swap Questions?

cmpickett

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I currently have an 81, which came out with a V6, that has since been swapped to a Pontiac 400.

I also have a Chevy 496 out of a 1978 or so C10, I believe.

I want to put the 496 in my Firebird. I have a th350 automatic 3.42 gears in it.

What will I need to do this swap?

Such as wiring, motor mounts, what headers will work, etc.
 
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Munkyslut

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Hi there, you are a new member, so welcome aboard; this is a great forum!

BBC into a 70-81 Firebird is no different from what Chevrolet did from the factory from 70-72.

You can use any early 70’s big block Camaro upper & lower motor mounts as the cross member is the same pressing.

You’ll need to swap the transmission tho as the current Turbo 350 won’t have the correct bolt pattern, not a bad thing really as you could then find a nice donor Turbo 400 which is far better suited to handling a stroked BBC.

Exhaust would be as early as Camaro, so header choice is huge.

There is no problem with using the existing trans cross member either.

The wiring couldn’t be simpler. It’s the same distributor wiring and location for HEI, and even the starter is on the same side.

Sounds like a good swap, that car will be huge fun on the street! 💪🏽😍
 
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