Ford Repair: 2000 Mustang GT, roots blowers, centrifugal supercharger

Question
I would like to know if a blower from a 2000 mustang cobra would be any better or worse than a centrifugal supercharger on my stock 2000 mustang gt? I ask this because I can get a blower for a lot less money. Would there be any advantages or disadvantages?

Answer
Juan-

  They're actually 2 totally different types of blowers.  The one that came on the '03 Cobra (not the '00 Cobra) is a roots blower.  Roots blowers are a lot like turbos in the fact that they make boost in proportion to throttle position.  With a roots blower you can nail the the throttle wide open and have full boost at about 2300rpm and it keeps steady after that.  A centrifugal blower make boost in relation to engine rpm.  So say the blower is rated at 14psi.  At 2500rpm you might see 4 or 5 pounds of that boost and 8 to 10 pounds at 5000rpm.  The maximum boost is at maximum rpm so the engine needs to be wound up to make good boost.  The roots blower is, however, usually less efficient than a good centrifugal kit.  But the '03 Cobras come with decent intercoolers.  It's all a matter of preference.  Procharger is actually getting ready to introduce a centrifugal blower for '03 Cobras that has a VERY high step-up ratio so it will produce more boost quicker, but it still won't match the Eaton roots blower that's on the car from the factory.  Hope this helps.

Steve