Head lift/flow formula
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Joined: Mar 2005
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Head lift/flow formula
I'm considering buying new heads for my car, and I'm wondering if there are any guidelines for choosing intake runner size? From what it looks to me, intake runner size affects exhaust flow - larger the intake runner, the more flow through the exhaust port. Obvoiusly, the cam must be able to supply enough lift to meet these flow numbers. should there be a ratio of exhaust flow to carb size? engine size/rpm? I guess from this I'll be able to choose the proper intake runner size.
By the way, I've got a 454, and am planning to buy a nice set of heads so that I'll never have to do it again. Maybe someday I'll take it to a 496, but not in the next year or two... right now I'm thinking CFE heads with a 330 intake runner, but this might be too big - should I go with 310?
Thanks,
Eddie
By the way, I've got a 454, and am planning to buy a nice set of heads so that I'll never have to do it again. Maybe someday I'll take it to a 496, but not in the next year or two... right now I'm thinking CFE heads with a 330 intake runner, but this might be too big - should I go with 310?
Thanks,
Eddie
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From: Corsicana, Tx
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To really help you we will need a lot more info. What are you planning to do with it? Do you race it or just street driving? Cam? Hyd, solid, flat or roller? No need to put a set of heads on that like RPM ranges the cam can't run to. Are you willing to use a taller hood to get a better intake? Headers? What is the rest of exhaust? Trans? Auto/Stick? Converter? Gears? A/C..power stuff...etc etc.
All of this stuff is necessary to decide something as big as heads.
All that said, I can't imagine that an average 454 would need anything more than the 310's..whch BTW the CFE (Canfield) CNC'd 310's are some nice heads!
Hey this is a breakthrough..for once Jim isn't picking the biggest heads!!
Double check ex ports height. Most aluminum race type heads have raised ports which will cause possible header issues. Also plan on possible pushrod changes etc to match taller valves and stuff maybe.
Might look at the Brodix Race Rites..they are real nice too! If you want the CNC stuff as set of AFR 315's or some M2/TechWeld Brodix will do well.
JIM
All of this stuff is necessary to decide something as big as heads.
All that said, I can't imagine that an average 454 would need anything more than the 310's..whch BTW the CFE (Canfield) CNC'd 310's are some nice heads!
Hey this is a breakthrough..for once Jim isn't picking the biggest heads!!
Double check ex ports height. Most aluminum race type heads have raised ports which will cause possible header issues. Also plan on possible pushrod changes etc to match taller valves and stuff maybe.
Might look at the Brodix Race Rites..they are real nice too! If you want the CNC stuff as set of AFR 315's or some M2/TechWeld Brodix will do well.
JIM
