CFM Per HP

[jsicfy]

Does any one here know a mathmatical formula to convert the cfm flow of somthing into how much HP it will support? Like if it were to flow 600 cfm and support 600 hp.

 

[zross1]

That's a good question. Sorry I don't know the answer. Hopefully someone does

 

[Kevin Jewer]

Unfortunately, CFM is meaningless unless it is standardized. You need to know the mass of the air, since that determines the mass/weight of the fuel you can burn (air:fuel is a mass/weight ratio). Thats why it drives me nuts when turbos or compressor maps are rated in CFM. If you can find out in Lbs/min (which is becoming much more popular thee days) you can get an idea. As a general rule of thumb, every lb/min of air is good for 10 HP. Now, several factors affect this, mainly how efficiently you use that air. AFR, timing advance, etc. Its fairly accurate on well tuned cars.

Edit> If you know the temperature and pressure, you can convert CFM to lbs/min by the way. The formulas are out there on the internet I'm sure.

 

[jsicfy]

I found that an average 1.5 cfm is flowen for every 1 HP

 

[loreak]

divide cfm by 14.7 and that is lb/min

 

[kpt4321]

divide cfm by 14.7 and that is lb/min

I hope you're joking....

Edit> If you know the temperature and pressure, you can convert CFM to lbs/min by the way. The formulas are out there on the internet I'm sure.

Like he said, you need temperature and pressure to convert.

 

[gasguzzler]

To get you into the ballpark (engine efficiency and temps have an influence also), but take CFM x .069 = estimated lbs./min
lbs./min x 10 = estimated HP

 

[1fast97gsx]

divide cfm by 14.7 and that is lb/min

I think you are talking about converting from bar to psi .... 1 bar = 14.7 psi.

 

[doug]

If you know the temperature and pressure, you can convert CFM to lbs/min by the way. The formulas are out there on the internet I'm sure.

There was a thread a while back on here about it:
http://www.dsmtuners.com/forums/showthread.php?t=20184

 

[kpt4321]

There is some great information in that thread, thanks doug! Good job setting this up for the archives and such!