[hgiv]

My thoughts around additional machining expense were related to the extra cost of reworking the heads, possibly needing extensive valve work. Also wasn't sure about piston options that might require extra consideration.

I'm glad to hear that that wouldn't be anything particulary extra and that 350 internal parts options are available . I had heard that this was not always the case.

[scott06]

Originally Posted by hgiv

My thoughts around additional machining expense were related to the extra cost of reworking the heads, possibly needing extensive valve work. Also wasn't sure about piston options that might require extra consideration.

I'm glad to hear that that wouldn't be anything particulary extra and that 350 internal parts options are available . I had heard that this was not always the case.

If originality matters send your core to someone like Len Williams and have him rebuild it. If it doesnt matter get the 400, especially if you want more power.

here is what butler offers for 350 pistons

https://butlerperformance.com/c-1394...0-pistons.html

some of the less common engines the parts can be somewhat higher cost. For example the pistons for my 65 389 the ross custom milled dish pistons with rings and pins etc were about $1200 where as similar pistons for a 400 are $850 -900. Ok the cost is more but $400 doesn't move the needle in the entire build cost.

other things to think about is getting forged rods and aftermarket crank - depends on how much you want ot lean on it. Id say if you have 250k on the factory engine as stock rebuild is probably ok .