Lagavulin

It is a 928; I usually post on the 928 board so everyone knows which Porsche it is. However, thank you for bringing it to my attention so I updated my sig accordingly. You can see it on page 2 of the link in my sig if you're interested.

I agree 100%! But I would like to see some rock-solid proof which supports our position.

I'm guessing no as a turbo and a centrifugal blower are very similar.

By the way, beautiful car! I love the 993's as my Dad has one in black metallic with a red leather interior; it is awesome. The flairs over the front and rear wheels are so 'muscular' looking, something the 996 lacks.

Danno

When comparing turbos vs. superchargers, you can't use black & white, all-or-nothing terms. Quantitative numbers must be used. They both have optimal efficiency ranges and using either outside of it's best range will result in negative effects. The turbo's backpressure is only a concern when a small turbine is used and boost is increased beyond a level such that the turbine can't provide the required spinning power without introducing excessive backpressure. A similar thing can happen in a supercharger if you juggle pulleys in such a way that you're spinning the super at too high of a RPM ratio in order to build big boost. The power sucked out of the engine to drive it goes up exponentially. The AutoUnion F1 cars that used superchargers lost 150hp to driving the compressor. All that to make a measly 400hp. It all comes down to numbers.

In which case, larger numbers are better! How about quad-turbos, eh?



For some real tech, forget blanket statements and look at some real research. Check out these SAE papers:

#450053 ___Turbocharger design and application
#600450 ___Developing the turbocharger for its application
#620247 ___Turbocharger controls
#660133 ___Influence of turbocharger characteristics on supply of air for high speed diesel engines
#660473 ___Effect of turbochargers on engine performance
#690033 ___A theoretical study of the flow in impellers of mixed and radial flow compressors
#790065 ___Compressor and turbine specific speed on turbocharger efficiency and performance
#790066 ___Centrifugal compressor development for a variable area turbocharger
#830014 ___Turbo charging for fuel efficiency
#830143 ___Comparison of the 3-cylinder DI-diesel with turbocharger or Comprex-supercharger
#841285 ___Comparison of a turbocharger to a supercharger on a spark-ignited engine
#870704___ Supercharger versus turbocharger in vehicle applications
#951882 ___Very-high-speed, hydraulic-turbine-driven supercharging system
#972676 ___High-speed, hydraulic-turbine-driven supercharger system and controls optimization

Lagavulin

Danno, very nice post!

I will certainly look at those papers and see what they have to say, and learn from them; I can care less about 'being right'.

Thanks for the material...

Tito 911

where do I find this staff?