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A couple of things that haven't been mentioned... First, be aware there is so much variation between wheel dyno's (brand to brand) that comparing your numbers on a Mustang Dyno, for instance, to your buddy's numbers on a DynoJet, to another buddy's numbers on a DynaPak, can be very misleading. So... given you've apparently already made a dyno selection, the key during engine development is to keep going back to the same dyno (with the same operator, if at all possible).
The Megasqirt system (at least on the 142E) will not currently legally fit within the SCCA Improved Touring ruleset, so most IT racers (myself included) use the D-Jet system as-is. Almost. It is typical to run fuel pressure at 37-41 psi vs the stock recommended 28. This puts the A/F ratio in the desired range with no other FI mods whatsoever. Probably wouldn't be practical on the street, but keep in mind we don't give a hoot what happens below about 5000 rpm, so we're happy.
Everything I've seen puts the drivetrain loss on a typical ITB 142 at 25-30 hp. BUT again, this is going to depend on how optimistic or pessimistic the wheel dyno numbers happen to be on your particular dyno. On a DynaPak, which is a true load dynamometer (unlike inertia roller types), the consensus seems to be that 120 rwhp is typical for a fresh B20E in IT trim; half point bump to 11.0 to 1 compression, good tuned racing header, balanced and blueprinted, no other mods. If you do the math, this would indicate something on the order of 145-150 flywheel horsepower.
Gary Learned
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