EARLY HEADS ON A LATE 360

[JERSEYJOE]

WITH NO OTHER CHANGES WHAT WOULD THE STATIC COMPRESSION RATIO BE IF YOU INSTALL EARLY ( 1970 ) 390 HEADS ON SAY AN 87 360? I'M GUESSING IT WOULD GO UP .5 FROM 8.5 TO 9.0?

[AMX69PHATTY]

Spreadsheet I made shows 8.48:1 stock with 57.92cc & 9.07:1 with 50.60cc on an otherwise stock 360.

[JERSEYJOE]

Thank you. are yhere any issues with chamber shape of the 50 cc head and the late model 360 dished piston?

[AMX69PHATTY]

I'm no expert, but don't believe so, pretty sure AMC kept combustion chambers
pretty much the same shape all along, just shallow or deeper.

[tufcj]

I'm running 291-C heads on the 75 360 in my CJ. Running stock pistons, stock bore. No problems at all, just slightly better compression.

Bob
tufcj

[JERSEYJOE]

I HAVE AN 87 J-20 THAT HAS SOME BAD VALVES, LOW MILES. I WAS GOING TO PULL THE HEADS AND PUT A SET OF 70 360 HEADS ON SINCE i HAVE SEVERAL SETS AROUND. MIGHT EVEN THROW IN THE EDELBROCK CAM I HAVE LEFTOVER. TRUCK IS ALMOST RUST FREE

[73hornut]

I HAVE AN 87 J-20 THAT HAS SOME BAD VALVES, LOW MILES. I WAS GOING TO PULL THE HEADS AND PUT A SET OF 70 360 HEADS ON SINCE i HAVE SEVERAL SETS AROUND. MIGHT EVEN THROW IN THE EDELBROCK CAM I HAVE LEFTOVER. TRUCK IS ALMOST RUST FREE
Should be a good combo, also add crane valve springs and new retainers and keepers.