[BLOWNBLUEZ06]

Originally Posted by Z28usmc

How about this for proof: Take an 03 Cobra. It comes with a roots style Eaton M112 from the factory. If you put full boltons, port the SC and tune it within an anch of it's life you MIGHT get to 550 RWHP. However- if you bolt on a twin screw KB or Whipple you ROUTINELY see RWHP #'s 600-800 depending on supporting mods and size of blower. The proff really is in the numbers- you can believe them or not believe them- your choice.
Manufacturers go with the HEaton because it's FAR cheaper to mass produce. You would add 3-5k to the price if you added a twin screw. Most manufacturers shy away from that kind of hike for fear of losing customers.

I see you have done some homework, however show me a KB powered LSx car making 800rwhp. The Magnuson MP/Eaton TVS product is making the #'s on the LSx engines. I have spent some significant time tuning and logging a 2.8l KB 402 and am not impressed with the #'s all. If efficiency was so high, then tell me why the IAT's are so high. This is even after fixing KB's engineering failure of an IAT setup. With a Magnuson MP112 and spinning the crap out of it, IAT's were 160 degrees at the end of the 1/4 mile. With the KB, they're 250 plus. If you're wondering about my tuning, don't bother. He took it to LMR for a retune because I sent him home to fix some issues and he wanted "the best" They did their best and that car isn't making over 600rwhp. Mustangs may like them, but LSx engines don't. Forget about reading. This is real world. I've seen it many times now and the crappy #'s keep coming from those not too embarrassed to post them.

If you insist on a PD system, TVS is the way to go. Period!