Originally Posted by Evolvd
How did you come to that conclusion? If the Dyno is jacked up can we be certain that the hp/tq numbers posted are accurate?
They are not accurate, that was the whole point of figureing out the RPM numbers based on the original graph and knowing what gear the dyno pull was made in.
I never trust a dyno graph with speed as the lower axis of the graph, becuase RPM plays a huge factor in the results on the dyno. Easiest way to tamper with dyno results is to use a bogus mph to RPM conversion in the dyno software.
Lets say we have a car that makes peak HP at 4000 RPM and it makes 300 HP at 4000 RPM. That would mean you are making 393.9 lb-ft of torque at 4000 RPM. Now if you convince the dyno that the car is actually at 6000 RPM when in reality it is at 4000 RPM, it will be convinced that the car is making that same 393.9 lb-ft of torque at 6000 RPM which translates to 450 wheel HP.
If you have an actual RPM signal from the engine going to the dyno, you can not fool it in this way... but if you don't use the RPM signal from the engine you need to input a "road speed to RPM conversion factor" into the dyno. If you do it correctly you get accurate results.... if you fudge the numbers a bit, your customer gets a really nice braging rights dyno sheet. For this reason I never trust a dyno sheet that reads in mph unless I do the numbers conversion for RPM.