Quote:
Originally Posted by jondee86
Ahh... good questions, and I don't have any good answers 
When I began this project I was only intending to target 15psi, but the
only pulley I could get at the time was a small one that was 20psi capable.
I did look at A2W intercoolers, but decided to see what was possible with
WI because it was easier to implement. These are the maps I was given...
Isentropic Efficiency
Volumetric Efficiency
I don't really fully understand how to interpret them. Hopefully, being a
modern twinscrew design, WI will be able to control the heat generation
up to some reasonable pressure. I am not obsessed with reaching 20psi
and will be quite happy if I can run thru the gears at 15psi now and then 
The supercharger I am using has an internal pressure ratio of 1.4 and my
engine has a compression ratio of 8.9:1 if that helps ?
Cheers... jondee86 |
I am sorry to tell you this but you better leave that 20psi pulley on the shelf.
I am attaching you the best and max high boost efficiency.
The First line shows where the charger is meant to work best which is 7-8psi @ 90g/sec or 12lbs/min. To make it more simple : With my 1.5L engine and a GT2560 turbo, I reach 12lbs/min @ about 3000rpm.
The Second line shows where the charger peak it's efficiency or in poor words begins to "overheat" the Air drasticaly compared to relatively lower pressures.
The Max working pressure is 15psi @ 170g/sec or 22.5lbs/min. To make it more simple : Compared with mine I reach 22.5lbs/min @ 5500rpm
If I knew your engine specs I could understand where this charger is with your engine. Specs needed:
- Engine size cc
- No of cylinders
- No of valves
To simply understand boost efficiency if you make a chart of boost vs air temperature you will understand without any compressor maps where your charger efficiency is. The chart will show elevated/abnormal air temperatures when out of efficiency.
Example :
Air Temp marking 30DegC at 5psi @ 3000rpm and 31DegC at 8psi @ 4000rpm.
DIFF 3PSI = 1DegC increase
Air Temp marking 34DegC at 8psi @ 3000rpm and 40DegC at 11psi @ 4000rpm.
DIFF 3PSI = 6DegC increase
A super efficient compressor would increase Air Temp equally related to boost differential at same RPM. Sadly no compressor is so super at high boost levels ...