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wireweld
04-27-2004, 19:26
how much flow, in cfm's, does a 6.5l TD displace?

gmctd
04-27-2004, 20:10
Well, 3.79liters is one gallon, so you have about a two gallon air pump of 6.5L, or right at 400 cubic inches per two crank revolutions. (396, actually)

200ci per rev times 3500 revs per minute is 700,000 cubic inches per minute divided by 1728 inches in one cubic foot is 405cfm at Baro.

Boosted to two atmospheres, Baro +15psi, that doubles to 810cfm.

Which is the equivalent flow of about a 4 gallon 800 cubic inch pump at Baro.

At 100% efficiency, of course.

[ 04-29-2004, 03:14 AM: Message edited by: gmctd ]

richard7
04-28-2004, 16:46
In the real life, I had calculated before that 400 CFM was about the max, because of boost pressure dropping drastically at higher rpm, and volumetric efficiency dropping as well.

gmctd
04-28-2004, 17:07
Show me your calcs (I've showed you mine), and remember - lots of numbers make my head hurt, so please be gentle. ;)

I round off out of necessity.

[ 04-29-2004, 03:11 AM: Message edited by: gmctd ]