Anyone know a conversion factor? I have always seen compressor maps in CFM, but turbonetics and a few others uses the more technically correct Lb/Min. I know it's hard to convert because Lb/min is dependant on density, but is there an accepted conversion for comparing compresor maps?
Compressor maps: CFM vs. LB/Min
- Thread starter Mikel
- Start date
RealFastV6
Plays with Trucks
- Joined
- May 26, 2001
If you divide lb/min by 0.069 that'll get you damn close for garret compressor maps. If you want the full formula based on inlet temp, etc, let me know. In order to compare to a compmap thats in CFM, you'd just use whatever values they used for inlet temp and air density I guess and run it through the formula.
Actually Mikel, the curves with CFM are more correct than the lb/min curves. A compressor like this is a volume machine, not a mass machine, in that at a given compressor wheel rpm and pressure ratio it will move a fixed cfm. The lb/min it moves is dependant on the suction temperature and pressure.
That being said, I believe the Turbonetics curves are lb/min at 85F and 1.5" Hg vacuum. At those conditions air density is 0.069 lb/ft3, so cfm * 0.069 = lb/min, example 600 cfm * 0.069 = 41.4 lb/min.
John Estill
That being said, I believe the Turbonetics curves are lb/min at 85F and 1.5" Hg vacuum. At those conditions air density is 0.069 lb/ft3, so cfm * 0.069 = lb/min, example 600 cfm * 0.069 = 41.4 lb/min.
John Estill
Similar threads
