Keith,
A Dyno Jet is the most consistent and reliable dyno numbers, regardless of what anyone says. The Dyno Jet is a very simple device where you mechanically accelerate a fixed weight and that's it. Dyno Jets do have some drawbacks.
1) The mechanical part of a Dyno Jet has never changed, and it doesn't change over the life of the dyno. A 20 yr old Dyno Jet is just as accurate as a new one. This is a big plus.
2) It's a well known fact that the software that the early Dyno Jet's used had flaws. Remember the old days when automatic transmission cars had a huge torque spike at the beginning of the run? You know, the ones where the AOD cars recorded 500ftlbs torque? Not anymore. Dyno Jet has improved their software to generate more accurate numbers. Current Dyno Jet software is very accurate. If the dyno has the lastest software, it's numbers are going to be right. Hence a lot of guys observed lower HP numbers than they expected at the Shootout last year. This is not because the dyno was stingy or the weather was bad, it's just that the numbers were accurate! Backstreet has the latest Dyno software. They do a large volume of high HP cars and race cars and their equipment is top notch.
3) Some shops don't use their equipment that much and some are running old software. Some do it on purpose.
4) Weather station data is critical to accurate #'s. Some shops have their weather station inside the dyno case which is subject to much higher heat than ambient, some never check their weather stations. Correction factors are always a big concern whenever looking at numbers. Remember, garbage in - garbage out.
5) Mustang Dyno combines a heavy drum with an eddy current brake. This means that the actual output of the eddy currents has to be periodically checked to verify performance, and recalibration is needed from time to time. Often times an operator won't know when the eddy current is running out of spec. Frankly it can be very hard to tell. The eddy current has a lot of advantages - increasing load for turbo cars, steady state tuning for speed density cars, etc. But it has it's limits too.
6) Dyno Dynamics is essentially pure eddy current. This means that the results are 100% the responsibility of the operator and his machine. It is very easy to manipulate DD numbers all over the place, and/or to enter false calibrations. It is for this reason that DD dyno's are not favored for "internet racing". They are great tuning tools, but you have to be very careful when comparing numbers. I've seen DD numbers much higher than Dyno Jet, and I've seen them much lower. It just depends. There was a guy on the original SCCOA top HP list claiming 340rwhp @ 4400rpm on a stock longblock. He had Dyno Dynamics dyno sheets to prove it, but that didn't make it realistic. There are other examples.
So to your comments about power numbers, they are just numbers. Forget about it. Sorry, but that's all you can do. Your car didn't make any power at all in my opinion because we never got to the point of being able to test actual power, we were only in the middle of tuning and never got to a power #. You have to sort out the ignition issue we were having and finish the tune before anything can be said. That and get to the track.