Pontiac 350

[Makoexpress]

I currently have a 350 and was wondering if I sent it out to a machine shop if it could be turned into a 400 or 455 seeing how I believe all Pontiac blocks started out the same. Obviously I would have to swap the crank, pistons, and upper end etc. but is it possible?

[2002Z4CSS]

I think it is possible but you may just want to get a 400 or 455 short block. Many are for sale.

[Nocooler]

No you can't just bore it to a 400 or 455.

The liners aren't that thick.

[Makoexpress]

Forgot to mention the block is a 73.

[TrickyTransAm]

You can find Pontiac 400's ready to go and running if you do some searching. I found a few for around $300 complete, but they are high mileage pulls generally.
Even better, there are 421's out there too...but theyre pricy. Same with 455's.
A 389 tri-power in that 68 would be a blast.

If you do find a 400, you should look for a set of 326 iron heads. If my memory serves me right, they bolt onto the 400 and raise the compression into a healthy 10:1. (Any devout Pontiac guys confirm this for me?)
That would be the dirt cheap route to go.

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