Does it even matter anymore?
Just give me something, anything will do.

 

Well, since turbochargers ARE superchargers, the question ought to be: "What kind of supercharger?"
The answer depends on what you wnat to do with the car.

Street driver? Probably a mechanically-driven positive-displacement supercharger.

Racer? Depends a whole lot on what kind of racing and the rules (if any) of your racing organisation (if any).

A turbosupercharger (yes, that's the whole name of it) will probably give you the highest peak horsepower of all, but may not have the best driveability.. good chance that this is the best choice for racing IF your racing organisation allows it -- and some of them don't!

A mechanically-driven centrigfugal blower will give you good high RPM HP, but not as high as a turbo -- but the turbo will have that annoying lag (not as bad as it used to be, but there's still some there even on the best of them).

A mechanically-driven positive-displacement blower will give you the best low-end HP and good HP "under the curve" across the RPM band, but it will drop off at the high RPMs. This is good for street use -- you get the power down where you usually drive.

The axial-flow blower looks to be a good match for the rotary engine, but we will have to wait to see for sure.

 

If you don't think, that you can improve your driving check out the Laguna Seca Run that a professional driver did in an RX8, then go rent Grand Turismo, and try to duplicate the run with an RX7.

http://www.mazdausa.com/MusaWeb/disp...eParameter=bod

I know games vs real world, but once you get a somewhat realistic idea of how hard that course is, you will be suprised at how fast, they can run the RX8 through it.

 

Not sure what you mean here. How broad are you defining this ? I think in most cases people define these two sepearately. Superchargers being belt driven off the engine, turbochargers being from the exhaust gases. Yes there are several types of superchargers : Roots positive displacement (Jackson Racing, Blitz, etc), Centrifugal (Vortech, Paxton, ATI, etc), Lysholm (similar to Roots, but with two rotating screws(Whipple). Turbos using spent exhaust gases from the engine to drive it's turbine impeller wheel.

I agree with you that there are different designs for different uses. They usually describe the Roots type as "The king of drivability" because powerband is proportional from just off idle to redline. The Centrifugal is similar to a turbo (in design it is close to a turbo, but belt driven off the engine) makes more peak hp, but at the expense of low (& sometimes mid) range hp.

Turbos can be different sized. A small one needs very little exhaust backpressure and spools quickly(delivers hp at a low RPM) but runs out of steam at high rpms. A large turbo has the opposite affect (gets massive hp at high rpm, but takes longer to deliver boost, hence "lag".) If you look at the 93-95 RX7 it was a sequential turbo delivery system. A small turbo, then a large turbo.

This explanation was not for Bob (as he to knows what he is talking about), but for those wondering what to get. Hope this helps more than what the other posters have already given.

 

for the rx8, i would go turbo because its better for cars that like to rev high.

 

Yes, I imagine a turbocharged RX-8 would make very high peak horsepower.

But, playing the Devil's advocate here, where does the RX-8 need the most help with power? At low RPMs, that's where.

So the question is, do you want a car that has very high power once it gets revs built up, but is slow off the line (great for racing); or do you want a car that has a little less max power, but higher power at the low RPMs and comes off the line strong (good for street)?

Ain't no easy answers.

 

I'm thinking about the Blitz SC for that exact reason. I want more low & mid range power. But if it comes out at $6K like many of their other units do that is a bit pricey. I am intrigued by the SFR/SSR turbo package though as they are claiming 300 whp. I think if I got 240 whp from the Blitz unit that would be amazing (just dynoed my car at around 185 whp). I hear (mostly from the SSR thread) that the Greddy unit might be a small turbo.