pump gas build

beebeeri000 said

i was wondering if i could get a little guidance on a pump gas build. im starting of with my '73 225 block crank and head and i was thinking about going with stock connecting rods with flat top pistons and a cam from oregon cam grinders with 234/228 @ .050”, 262/252 adv, .476”/.479” lift, 108 lobe separation. this will be my first time building a slant so i would appreciate any advice. ive also been curious about shaving the block and/or head but i dont wanna increase my compression too much and like most stuff i cant find consistent numbers.

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You don't "find consistent numbers". You have to "measure" what you actually have. "Most times" the slant 6.....and really all of Chrysler's engines of that era fall dismally short of their advertised compression ratios. Usually the slant 6 is down in the 7s. This is because of deck heights taller than spec, combustion chambers bigger than spec. It's just a reality of how they did things. So the best thing is to get it to a competent machine shop and let them inspect and measure everything and go from there.

"All that said" generally speaking the "obligatory" amount to mill the block and or head, is .100". This will generally get compression touching 9:1. But again, measure first.

If it was me, I'd take it off the block, and just have the head lightly milled to clean it up. But you NEED to measure to see where you are first. Hope that helps.