Kevin, old friend! Long time no post! How have you been?

And Russel, it's not the 1/4 mile et that takes forever, or even matters. It's the trap speed that's important. I've used trap speed for years to calculate hp, and assess if what I just did to the vehicle did any good. For years I used the same stretch of road, 1/4 mile measured with a steel surveyors tape. Couldn't control ambient temp or weather, but if you could do the runs close in time, it was quite accurate. Of course, like a chsssis dyno, it measured rwhp, not crankshaft hp, but rwhp is real world hp, anyway.

The formula is"

HP = (mph/230)^3 x lbs weight

If your 1/4 trap speed is 75 and your weight when run is 3400lbs, the answer is 117.9hp at the rear wheels, if I did the math right on the back of the envelope.