[Wolf1]

Please keep in mind the EATON is a hybrid or improved design roots style supercharger.

It isnt a twin screw, but it isnt just straight rotors... so you have a higher effeciency roots, but it is still a roots.

Now for boost over say 18 PSI, you need to look to a twin screw up to about 25 PSI.

Beyond 25 PSI, well that is the realm of the turbo and centrifugal supercharger.

Turbos can be setup and run at any RPM and therotically are only limited by the amount of CFM they can supply the engine... so if sized right you could build insane levels of boost... 40, 50, 100 PSI... but not on our engines.

Now if you want old school high boost, well look at the 3-71, 6-71 and 8-71 "blowers" These blowers suck in the effeciency range and eat a lot of HP to produce HP. But they can easily hit 40 PSI.

Again all superchargers take HP to MAKE HP.

A turbo doesnt require hp and can supplier larger levels of BOOST, but it also generates an insane amount of HEAT.

A turbo in my opinion is the easiest to install and at the same basic levels of boost of most supercharges (5-7 psi) you would see more power from the turbo, since you have no loss of hp to drive the supercharger, but you do suffer lag.

Above 7 PSI and the heat gets ugly, even at 5 PSI, intercooling can be critical to substained performance on small displacement engines.

Now remember engines like the 924 have junk for volumetric effeciency, the head design sucks. You can still make power... but well the best thing would be to use a different head, or otherwise increase volumetric effeciency and use the supercharger to compensate at low RPM for a lack of good low end torque.

In other words if you heavily modify the 924 stock head, you tend to loose low end torque, but superchargers make loads of low end torque... so...