Built Engine Versus Stock Engine as of 8-29-03
JE Flat top pistons, Houston Performance CNC P/P heads, BBK longtubes open both runs, HP Nitrous grind cams, HP Motorsports short runner intake, SHM Valve Gear kit.
Both runs were open exhaust, slicks on the rollers. Stock engine run was first run of the day in March when I was really working on nitrous system stuff, so is a little lower than it could have been from an absolute value. The engine never showed more than 13 hp higher than this number, however.
Note that the power is less than stock below 5400 rpm and much better than stock above 5400. At 6800 rpm, the gain is a whopping 77 HP, but the peaks are different by 48 hp. Obviously, a rev limiter reset is needed, if the peak on the new motor is as high as 6700 rpm. If I could shift it at 7600, I could bracket the power peak a lot better than shifting it at 6800.
Now compare the 100 hp NX wet kit jet curves.....
These runs were with the 100 shot rich kit just too rich for best power. I have some work to do on it. Note that the shape of the curve is such that the rev limiter is still holding the engine back since the peak, what little peak there is, is still closer to 7000 rpm than it is to 6000 rpm.
In its current state of tune, and with the rev limit of 7050 rpm, the area under the curve from 5000 rpm to 7000 rpm is about the same for the new and old motor. This was confirmed that night at the drag strip. But I had a bent wheel and couldn't really test the car. I can say that it launches a little weaker than before, but pulled good to the rev limiter.
This graph does not tell the whole story. The motor one does. Will update the nitrous tune this coming week. After the rev limiter problem is solved.
Joe Lynch