Thread: 402 BBC buildup - combos???

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Those 781 likely dropped your c/r quite a bit. I dont know who told you 113cc....I think that's mis-posted somewhere. I have worked on several sets of 781's and 049's, and not one was ever less than 118cc. Mortec lists them at 118 or 119cc. So unless you had them milled quite a bit, they are more than 113cc. Is that what you meant by too big?? Other than the large chamber, they are great heads. Runners are about 256cc or so, nice size. But a set of closed chamber heads would get your c/r up. It all depends on if you still have the stock pistons in there. And you wont see any added benefits of the bigger valves unless you are running over 5K or so...the stock valves flow surprisingly well.

my block is decked .060, and heads are decked .060. i didnt know the chamber size so i did a quick google search and they had claimed 113. but yeah i jus checked mortec and i would trust they're stats. and as being too big, i mean do you think they would flow too much and not be able to pick up at low end. I dont have my sheet by me of my flow. but i do need to cut the intake to 2.19 to bring the % to 75%

ill find it in a bit and post the flow..
im running a forged crank, rods, and KB pistons