318 head porting for the average joe
Something is wrong with the 318 in your car, it should run fine as is. Maybe the Lean Burn stuff. Have you played with the carb and timing at all? Back to your question. See post #260 and thank Justin. If that gets you to 190 cfm, that is where 360 heads flow stock. If you are sure they are not cracked, I'd mill them .020 and .019 on the intake side while you are at the machine shop. Use viton positive seals and 340 or equivalent valve springs. Find true TDC while the heads are off and degree in your cam. I'd run the 260 duration cam over a stock 360 2 barrel cam. Use a double true roller timing set. I put 4 barrel carbs on everything and a good TQ is the best, but the others you have will work nicely.