How much is too much ? - calculte required flow ?

[Unkl Ian]

How do I go about calculating the required airflow,
if I know cylinder displacememt and rpm range ?

Putting big ports on a small motor won't get the effect I want.

I'm sure I had a link to a airflow calculator,but can't find it now.

Thanks.

Ian

[larrycavan]

Ian,

Here's an online calculator
[URL=http://www.wallaceracing.com/flow-rpm.php[/URL]

[larrycavan]

Here's a couple from Superflow that should come in handy.

RPM= [2000/CID] X CFM@10"
For a full out racing engine use 2200 instead of 2000.

HP=.43 X CFM@10"

Safe Peak RPM = 22,000 / in. stroke
Max Peak Power RPM = 27600 / in. stroke

The last two use 3700 ft.\min piston speed as the safe limit.

Larry