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1017 Views 13 Replies 4 Participants Last post by  CHEMMINS
Anyone know how many lbs/min of air an unmodified head with factory cam will flow at a given pressure? The reason I ask is; if a turbo is advertised to flow 80 lbs/min, but our engine requires a pressure of 60 psi to swallow that 80 lbs/min, that high of a PR has forced the charger off it's map and is incredibly inefficient.
Anyone have this sort of airflow info?
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Head flows about 150 cfm stock. You'll need to figure out the conversion from cfm to lb/min.
150 with how much pressure forcing it through?
150 would be with 28" H2O which is equivalent to 1 psi. It is actually like 27.7X to 1 psi...but you get the point.

And that is measured at .400 inches of lift.
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Now if you are bored....take all the info posted and plug it all in here - Turbocharger Compressor Calculations and have yourself some merry math.
Kaiboshed that Now I am looking at Carls Super/compounds setup. Probably a 3.3 whipple feeding a silver 66 over a 95+mm.

Already have a silver 66 in the garage. Looking for a used head for cheap to get worked. Sold the spare 351's.

I figure if I am going to do it.....might as well do it right the first time. Slow build everything on the shelf and take the truck down all at once and do it all.
Yeah, well your plans changed a bit too I
A "free" week still costs
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