mike13

iTrader: (27)

Is there a formula or method for converting lbs of airflow into horsepower numbers? I see this on turbocharger websites but don't know how it's calculated.

For example datalogging my car I see 56.92 lbs/min @5500rpm

tecmec

iTrader: (1)

Hmm. Here is a good resource. And this one.

mike13

iTrader: (27)

Thanks I tried google but wasn't asking the question correctly. Garbage in garbage out. thanks again

cablebandit

iTrader: (37)

more accurate to convert mph and et to hp made/applied

psiconversion

iTrader: (5)

I agree with cable bandit. Although there is a direct correlation between the amount of air coming into the intake and the amount of energy the engine is capable of making. Problem is you dont know what true volumetric efficiency of the engine is so you dont know how much of that air you are actually burning to make power.

edcmat-l1

iTrader: (10)

http://www.land-and-sea.com/dyno-tec...using_bsfc.htm

http://books.google.com/books?id=E_T...mption&f=false

With a little math, you can calculate it by either BSAC or BSFC, but the problem with doing it using your scanner data, is any changes in the program that may or may not be entirely accurate will skew your results.

The bestest way is with a calibrated airflow meter, and fuel flow meter such as those found on engine dynos.

RedHardSupra

iTrader: (1)

i usually go with 9.0-9.5rwhp per lb/min of airflow and 4.5lbft per 0.01g/cyl of airmass. it's a ballpark, but it's been surprisingly accurate across many cars i've got to correlate between dyno results and scanner logs

mike13

iTrader: (27)

Thanks, I'm trying to understand how you can use all the different data to put together the bigger picture. Doing a pull on the street the car reached 56.92 lbs/min and 82% injectory duty cycle at 5500rpm so I let off. So far I know I need more injector or less boost

1999 Firehawk
3.73's 3200 stall
TC76 turbo, 8psi, 42lb injectors
ported LQ9 heads 9to1 comp, 221/221 561/561 cam
PE 12.5afr (car actually runs@ 11.0-11.5afr meth injection 100% meth)
17 degrees timing at full boost not a hint of KR