Forced induction on a 2.5 Liter 4 cylinder

[Jim Steck]

>> The Whipple unit as sold by Keanne-Bell and Bell Engineering is the best
supercharger. Gets boost lower and uses less HP. Tests done @ Ford show
that Eaton, Paxton etc for 8psi on 4.6L motor used 70 hp to make boost
while the Whipple used 35hp. Bell's kits are very well thought out. <<

If you test an Eaton supercharger at flow rates well beyond its design limits,
it MAY require 70 hp, but I have performance charts for the Eaton Model 90 (Ford
T'bird) and the Sprintex S102 (Whipple).  At 400 CFM and 10 psi boost (more than
250 hp), the Eaton requires 28.5 hp and the Sprintex requires 22.6 hp . . .
better, but not exactly half.

A typical adiabatic efficiency for centrifugal compressor (Paxton) at a pressure
ratio of 2.0 is 85 percent.  The Sprintex is less than 70 percent.  Sorry,
sounds like advertising hype to me!

Jim Steck
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