Quote Originally Posted by UselessPickles View Post
And my point is that if the difference is not primarily the type of forced induction (which I don't think it is, because both are a centrifugal compressor, and the turbo should theoretically be more efficient anyway), then there must be some combination of RIPP exaggerating their claim, or a difference in the calibration (tune) causing the difference in low RPM gains. It's the same engine on the same vehicle, so there's no sense trying to get into details of how port size, runner design, etc. can affect the results. All those details are exactly the same between the two vehicles being compared here, so it's irrelevant.



And if that's the case, then a dialed-in tune with the turbo should get similar results at those low RPMs where boost is similar to RIPP. I heard a rumor that a new tune for the turbo may have some low rpm improvements, so maybe Prodigy and RIPP won't be so far away from each other at low rpms after all.

Still no response from RIPP. Maybe they don't check their PMs on that forum.

Well, actually Turbos tend actually rob you of power when they aren't producing boost. They create back pressure on the manifold and that resistance has to be over come before you start to see a gain in power. The severity of this issue is based on the turbo size and the engine's size. Which is why when you sequentially turbocharger and engine you will notice the first turbo is small and it operates almost immediately producing boost. Then you have a bigger unit for higher RPM and higher power where the turbo's exhaust back pressure is more than over come by the immense HP and Torque gains.

And since centrifugal superchargers have the same basic deign they also have the same issues with lag. However, if you gear them correctly, you can reduce this lag at low rpm. Another plus is that your average centrifugal unit can run at much higher rpm ranges than the positive displacement model superchargers.

As for performance-- of course tuning a car for better performance at low rpm or high rpm will trump a car designed for daily driving under those conditions. But you just don't have enough information about each system to really say for example that if my turbo makes .75 PSI at 1800rpm I'm getting 800CFM and the Ripp unit is making 1100CFM at .75PSI Boost with 1800rpm. Then you could say oh, I see why my system isn't producing %40 percent more power at that rpm range because they have 300CFM more air in the engine than I do. And that is all we're telling you Useless Pickles you just need more technical information about the units to really do the analysis you want to do.

But, I agree that %40 increase in power at that rpm range seems hard to believe but it is possible to do.