Quote:
Originally Posted by chojuan30
But the load is not the same. So, heat, efficiency and wear will be less.
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Yes, the load will be less at 10 psi with the valve bleeding boost at 20k rpms than the load at 20 psi of boost at 20k rpms, but still greater than the load at 10 psi of boost at 10k rpms. This isn't an object spinning in the vacuum of space. There will be drag created by spinning the supercharger at 10k rpms beyond what is necessary. The drag will be from the bearings, from the interface of the rotors, from the air resistance, NVH, etc. Since a twin screw supercharger is always compressing air and not just pumping air like a roots supercharger, there were be the resistance of compressing air. Once the air is compressed, the boost would be vented, so there wouldn't be extra resistance from pressure building in the manifold, but compressing the air initially would be that much more wasteful and parasitic. There is no way around doing more work and wasting that work, and it not being more parasitic/wasteful.