TTMartin

+1

Adding boost puts you into classes where you have to spend lots and lots of money to be competitive.
Being competitive in BS or STR is expensive enough.

CKit

Sorry, got pulled away to work before I could finish the previous post.
That previous dyno was to show the pitiful low end torque of a Rotrex.

Even a Greddy does better.


I don't think anyone in their right mind would spend the money on a Rotrex kit when so many Comptechs are available for cheap. The "increased torque" of a Rotrex is negligible compared to a real turbo. If you're looking for torque, go medium turbo or Roots SC.

CKit

Me: previously centrifugal SC'd now a turbo convert.

psychoazn

Rotrex, MBC, and wastegate welded to charge pipe.

Quick rampup, more power on demand up to your maximum boost level as determined by pully.

turbo8765

A centrifugal blower (rotrex or any other) will never make more low-mid range torque than a positive displacement blower or turbo.

The problem with a centrifugal blower is that the boost builds with the square of the rpm. This means that if you have 10psi at 9k revs, you essentially have nothing on the bottom end. A positive displacement blower has a flat boost curve.

I've always thought that a low boost turbo would be the perfect setup for an S2000 DE car. A properly sized turbo (we could debate all day, but something like a disco potatoe or GT30) will spool early, preserve throttle response, and absolutely transform the motor between 3-6k revs.

I don't understand why none of the vendors have pursued this.

SSS

As noted above, A Garrett GTX 28r or 30r is perfect. The best the market has to offer as of now.