Up the VE percentage in the first formula.

 

How do you determine how much of an increase?

 

Good info. I kinda figured my stock TB might be holding me back a little. A bigger throttle body is definitely on my Christmas list.

 

At what RPM does a stock A4 shift at?

 

Looks like the stock one is already a little small for stock engines. I get 577 cfpm with 100%VE for a stock engine.

Doesn't valve lift and come into play?

Dan

 

Well crap I need 658cfm just on engine alone. Im still using the stocker.

 

5700 1-2
5800 all other gears.

 

what does a typical 52mm like a bbk or a ported stock one flow about?

 

Ken, thanks for the info. By the way, I took a peek at your website, I love the opening picture. LOL That really somes it up. If that damn thing would fit I'm sure someone would bolt it on.

Scott

 

LOL thanks. Yeah i actually need to get around to updating since i dont even have that SS anymore.

 

52 mm flows 790.

 

Actually, BBK advertise 750. Ours flow in excess of 775-800 depending on the work done.

-Shannon

 

hey nomad i sent you a pm..

 

Thank you! I know our stock tachs are not dead on, but while racing it appears that my tach goes way past 6, is that right? Since it should be shifting below 6,000 rpms? Anything to be concerned about?

 

your probably asking for trouble using 100% VE in this calculation...a typical engine will only be in the high 80's maybe 90's, and that can make a large difference in how much airflow it actually needs. Boosted apps can exceed 100% VE by quite a bit.