I'm not sure I follow? Motors love boost, it makes the engine far more efficient for power vs. ci. I think it's the gasoline that doesn't like boostOriginally Posted by Byrdman
As a rule of thumb, you can typically add 7-8 deg F per lb of boost with a good screw compressor. The curve is typically pretty linear, not like a roots where it just gets hotter and hotter as boost increases. PSI's rotor design was originally done in the 50's. We used something very similar that was made by Sprintex in the late 80's and early 90's. It's technology is no where near the later generation profiles. The amount of air that can be flowed vs. size is drastically different from early generation rotor designs.
To note, we have different pressure ratios which makes a screw compressor better at different boost levels. PSI typically has too high of a built in pressure ratio which limits flow, parasitic losses and temp. Until you get to 30+lbs of boost, your losing something at lower psi's. Thats before you add distribuition into the equation, PSI's have usually been poor at distribution, they have some plates and there are things you can do to make them better, but just bolted on, they will be a problem. Put 8 a/f meters on, you'll be shocked. Ours is within .5 a/f and 50 deg from high to low.
New motto for the roots guys, and I think I'm going to have to get some shirts made, "why be blown when you can be screw'd"