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Before we went to the Dynojet chassis dyno, I simulated Mike's engine
in Dynomation so I happen to have the relevent info on hand. Mike's
engine is a 393C (4.03" bore by 3.85" stroke Scat kit with Probe flat
top pistons, 11:1 on 92 octane) with unported CHI-4V heads, equalized
Blue Thunder dual plane intake, QFT 750 carb, a cam of specs:

239/244 (268/273) degrees dur. 0.605"/0.588" lift (less 0.018" lash), 108 LSA

GTS headers with these mufflers:

http://pantera.infopop.cc/eve/...562/m/4850059725/p/1

They are Cherry Bomb Extreme mufflers (p/n 545-7425, single 2 1/2"
inlet, dual 2 1/4" outlet) with Hooker tips (p/n 520-22202, 2 1/2" X 3").
The pipes are Dynomax 2" mandrel J bends (p/n 289-42310) cut to fit.
Each muffler has a removable insert in each tip. The inserts are packed
with ATV/Motorcycle muffler packing. Though Mike had two remaining
pulls we only dyno'd them with the inserts as I forgot they were removable.
The engine was also equipped with this paper element air cleaner:

http://pantera.infopop.cc/eve/...562/m/2010056465/p/1

> The dyno operator was surprised at how much power it made.

After the first pull, the dyno operator said "Well, I didn't expect that."
I opened my laptop with Mike's engine modeled in Dynomation and said "I did".
Dynomation has a mode that simulates a chassis dyno and it predicted 417 rear
wheel HP. If we'd remembered to remove the exhaust tip inserts, I'd bet it
would have been very close. Dynomation estimates the engine in the 525 HP
range at the crank.

> At the wheels, correct?

Yes. By way of comparison, a 5.4L Supercharged Shelby GT500 (stock except
for a K&N air filter set-up) made 392 RWHP.

Dan Jones
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