Originally Posted by lancerman

I made a casual statement in reference to your statements. You stated the car made 880whp the night before going to the track. And then it trapped 139mph. And then you were bragging that you are winning the discussion and this car is gonna make 900whp and shut everyone up. At least that is what i got from your statements.

My statement was to clear the air on how to calculate true HP. You seem to be under the impression the HP numbers this car is making at the dyno is correct. And anyone who tries to point out the contrary is an idiot.

There are three HP measurements worth discussing.
fly wheel horsepower = this would be the power an engine makes measured on an engine dyno measured at the flywheel. rolling road dyno = the power measured at the tires after HP is lost in the driveline. and third the track = true measurement of HP.

HP by definition equals the work done divided by the time frame the work was done in. This is very easy to calculate form having the weight of the car and the time it took to move that weight 1/4 mile. Thats why i stated HP calculators are far more accurate at measuring HP.

I do realize the car has to make a good pass to get the HP calculator to give an accurate reading. I wasnt there at the track so I cant comment on how bad the pass was. But I can comment on how fast the car should go using the HP calculator.

The FBI dyno says its making 880whp.
the HP calculator says with 1000 flywheel HP and 3650lbs. the car should trap 9.0 at 154MPH.

lets us know when the car does that then we will all apologize for trying to correct the HP numbers that are being touted here.

as a side note. yes dynojets read like engine dynoes. thats why tuners and shops love them. they give high numbers and that makes people happy and it makes the shop and tuner look good. as an example here. the X runs good on FBI dyno. gives great numbers. It goes to titan dyno and doesnt run good, it goes to track and doesnt run good. that doesnt look good from where I am sitting. what good is making big numbers if it only does it on the FBI dyno??

Maybe my suggestion to FBI was a good one? A dyno is a tuning tool. Its most important job is to mimic the load that a car sees when it is actually driven on the road. In order to check whether or not the dyno does that is quite simple. Run a log of car on street. do a pull in forth gear from 30 - 100. measure time from 50-90. repeat on dyno and compare time from 50-90. this number should be identical. If not then it is quite clear the dyno is not loading the car correctly. when manipulating the dyno to read high numbers you are unloading the rollers so the car looks like its accelerating faster than it actually does on the street. this is a bad thing. it throws the tune off. If I owned a dyno with loading characteristics I would do this test with every different type of car that came in till I had good setting to enter into the dyno for each type of car. At this point the dyno will read lower than a dynojet. but it will gives accurate tunes. whats more important? inflated HP numbers that are fun to boast? or true numbers and a car that runs just as well on the street and track than it does on the dyno ?