i know this is graveyard revival, but i saw some funky info in these threads.
mostly the power thoughts and reliability issues between turbos and S/C's. turbos make great power, yes. but mostly at a higher rpm, after spool has initiated and peaked. the same goes for centrifugal style s/c's.
roots style blowers on the other hand make boost off-idle. so, take in the inherent effects of a turbos "lag" and pair it with a supers "instant" power.
sure, the turbo will make more peak hp, almost every time, against a roots style. the roots style will provide instant torque and off-idle power, creating better launches, more out of turn power in a wider range of rpm and, if tuned and prepped properly, carry the vehicle more consistently/controllably.
not to say turbos cant be tuned, they are exceptionally tunable and can provide wonderful power outputs and powerbands.
it all depends on where you want your power to come in and how you want to control the power and how the vehicle handles the power.
personally, i am a fan of torque, as that is what carries the vehicles weight. in drag racing, road racing etc... hp does not carry a car down a track, and a driver does not "feel" hp, only torque.
neway, just wanted to touch on this. also, in addition to the top fuel comment earlier, yes these engines make insane hp, but are also robbed of approx 1000-2000hp because of the supercharger. a brand new 392 hemi crate motor cannot drive one of those s/c's.
the only reason they use superchargers is the ease of tuning, lack of extra "fallable" parts and the consistency of a S/C at any given RPM.
http://www.4x4abc.com/jeep101/torque.html heres some info on HP and TQ.
cheers.