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Head flow numbers

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Old Sep 5, 2010 | 05:31 PM
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donovann2o's Avatar
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Default Head flow numbers

I am wondering what flow numbers I can expect from a full port and polished set of stock 2004 HD heads. Thanks guys for the help!
 
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Old Sep 6, 2010 | 07:10 AM
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our stage I get 145 cfm @ 10", stage II heads are 155-160,stage III are 170-180 depending on what size valves we use
 
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Old Sep 13, 2010 | 07:36 PM
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Originally Posted by donovann2o
I am wondering what flow numbers I can expect from a full port and polished set of stock 2004 HD heads. Thanks guys for the help!
We offer heads from 150 cfm @ 10" and up.
The peak flow numbers are nice to see, but mid-lift,(valve goes thru that area twice) and how quick they climb are VERY important.
Scott
 
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Old Sep 14, 2010 | 08:05 AM
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Many things to consider here. The most important being valve sizes, percent of exhaust to intake flow ratios for good scavaging, and velocity. The numbers these guys are throwing out are pretty good for intake flow.
 
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