675 v 920 home porting

vghoon said
I have a 318 ,904, 3.23 diff gears in a valiant coupe here in aus that's just a fun cruiser.
+030, ldb4 intake, voodoo 701 cam, edelbrock 500, currently has 675 heads decked .050 & cranking psi is 165, and is a fun package to drive, From memory the 675 heads on the car are at about the 63cc mark.
Do I start home porting the decked 675 heads or 920 heads as I still have to buy & put hardened seats in the 920 heads to start with before anything else?
The goal is to home port as the Thread has inspired me.

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That's a beautiful VF Coupe.

Just use the 675's. Work out how far your pistons are down the bore and mill the heads a little to get the comp up a little more. If it were me I'd aim for 185 psi on premium 98

There's a VF sedan here in Sydney that the owner tells me he has a 318 with 11-1 comp on premium and runs 12.7's.

Keep us posted on how it turns out.