Posted By: sam64
head flow-hp - 01/27/13 11:37 PM
on a 470bb with a mp .590 solid,11.1 comp.,how much hp difference from a head that flows 290@.600 vs 315@.600?thanks,sam.
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on a 470bb with a mp .590 solid,11.1 comp.,how much hp difference from a head that flows [Email]290@.600[/Email] vs [Email]315@.600?thanks[/Email],sam.![]()
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that's why i'm asking,i don't see anyone advertising a hand or cnc port for x amount of cam.i guess i should have asked if it would be worth the change from 290 to 315.i'm not dwelling on big numbers just wandering if it's worth the extra$ to have heads ported.thanks,sam.
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There is not a real simple answer to that question. By the time you subtract valve lash, pushrod deflection, and a few other factors your 590 lift cam is not 590. When porting a set of heads they should be customized to match the customers combo. It is real easy to reach for that high flow number only to have mid lift numbers and air-speed suffers. Most guys use the simple factor of 2hp per 1 cfm but a lot of things come into play.
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on a 470bb with a mp .590 solid,11.1 comp.,how much hp difference from a head that flows [Email]290@.600[/Email] vs [Email]315@.600?thanks[/Email],sam.![]()
Quote:Quote:
on a 470bb with a mp .590 solid,11.1 comp.,how much hp difference from a head that flows [Email]290@.600[/Email] vs [Email]315@.600?thanks[/Email],sam.![]()
There is not a real simple answer to that question. By the time you subtract valve lash, pushrod deflection, and a few other factors your 590 lift cam is not 590. When porting a set of heads they should be customized to match the customers combo. It is real easy to reach for that high flow number only to have mid lift numbers and air-speed suffers. Most guys use the simple factor of 2hp per 1 cfm but a lot of things come into play.
Quote:the motor is a new build to replace the grenaded 440,the heads are the mopar eddies that came off the 440,been touched up not ported,car weighes 3250 race ready.probably run them as is this year,only 4 weeks till track opens.Quote:
on a 470bb with a mp .590 solid,11.1 comp.,how much hp difference from a head that flows [Email]290@.600[/Email] vs [Email]315@.600?thanks[/Email],sam.![]()
hmmm... i wouldnt recommend pulling heads just to do a port job...
are they irons? what heads?
what i would do, is shop around, lurk the boards find a top end for sale / heads intake
get offsets on them... heads ported at the same time. so your .590 lift becomes .630 and you have fresh springs/valves etc ready to go.
that would make a big difference. also if you go from 11.12 down to 10 something you may need to do some other work to stay legal. you could do some lightening as well and you will be down in the 10's
do it as an upgrade package... that way you can keep racing as you lurk and gather parts, and you will notice a much bigger change.
just taking your current heads off and having them ported and putting them back on is a ton of work & downtime with not as much return on your dollar
if you already have alum heads you could resell those