JG33

I think from memory the compression on the 400 with flat top pistons is 9.0:1 with open chamber heads (someone correct me if i'm wrong).

What would the compression be if I installed 302 closed chamber heads on it? I'm thinking it would be too high for 98 octane but not entirely sure.
Any ideas?

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460cixy

not a clue. but its not hard to work out if you have the clearance volume and know how many cc,s the chamber of the head is

gregaust

Just be sure to work it out carefully because the 4" stroke can really pump up the compression,more so than a 351..
One i was involved with with 351 flat tops and 302 heads was close to 12:1...The reason being i believe is the original 400 pistons are a fair way down in the hole..

JG33

I worked out on a CR calculator with:
59cc combustion chamber volume
-6.5cc piston volume
Gasket thickness 0.040
Piston .010 below deck?? not sure with this one I guess it depends on piston height?

Works out CR of 11.86:1..........still too high.

Can I get pistons with more negative volume?

Gives me

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shooterpcb

I have a complete 400 I am going to sell if you need an extra. $130 + ship. all there except carb and distributor. I got pics.

JG33

Already have one.

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CRUSHU F150

im interested

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ford 79 f150 4wd, lifted 6", 15 x 10 alloys,38.5 x 14.5 swampers, 400ci supercharged, c6, np205, 9" and dana 44, side pipes, big stereo, step side body