I created a program with Microsoft Excel that will take any winpep file (dynojet) and convert the chasis dyno number into an engine dyno number. There is allot more to it other than just dividing by .825, this also takes into consideration and driveline loss in addition to the normal 17.5%. For example, the more power you make, the more the converter slips and the more the results are skewed. What the program does is correct the chasis dyno numbers to the same driveline loss of a stock srt8 and it then divides by .835 to get an accurate engine dyno number at 100rpm increments. I can do this with anyones car as long as you can provide me with the winpep file. Just so everyone understands, the 17.5% driveline loss is from our original 426 that made 560hp on the dyno and 463rwhp on a chasis dyno without changing a thing. 626hp@6,000rpm/608tq@5,000rpm
Absolutely not. Its a simple measurement of hp/tq while eliminating driveline loss. Here is the chasis dyno sheet. In the second graph, you can account for additional driveline loss presented by an increased amount of hp/tq. The more power you make, the more the converter slips skewing the numbers. Up top, the converter has fully locked and there is no correction there, so it is a simple 519rwhp divided by .825 which puts us at 629hp. Im not stating these are exact numbers, just something close.
And thats why I love my motor well parts of it. Thanks for the call to day andy. Be talking to you again real soon
Excellent program Andy. Ya done good, but... While the program (software) is genious, it still will not give you a 100% accuaracy. IMO. I am sure it will be very close, but never dead on. Every cars static loss is gonna be different. And I still do not understand WHY everyone is so hell bent on dyno numbers? Dyno's are for tuning and bench racing. lol Take it to the track, that is where the pudding is. hehe Again, very nice program Andy. I certainly could not do what you did. :worthy:
I agree on the accuracy, but each car is receiving a different correction for static loss. Jons car does not have as much of a correction at 3,500rpm as Jeremys, but it has more correction at 5,700rpm. With the dynojet software, I can get real close to determining static loss through converter slip etc. I can only correct to what the stock car has for static loss, so you are right, it isnt an exact number, but it is very close or as close as you can get without actually putting the engine on an engine dyno.
626hp@6,000rpm/608tq@5,000rpm 567hp@5500rpm/606tq@4500rpm 600hp@5750rpm/596tq@4650 600+hp@4250-5500rpm/770tq@3800rpm
Concured. Again, AWESOME job on the creation. Now, maybe I will see this program for sale at Best Buy in the future? hehe
That is correct. They are not exact, but i would be willing to bet they are within 2%. If the entire calculation is wrong, that means the stock motors are not actually making 420hp, lol. Im more concerned with the delta between stock and after the mods. The delta is what I was really looking for when I set out to do this.