Originally Posted by shaodome

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Ugh....I don't know why this keeps coming up around the internet time and time again....

It is more boost because of the increased load usually as most electronic controllers lack any sort of algorithm to regulate boost...which is one of the reasons I like the AVCr. The profecB for example just runs on a dutycycle, it doesn't care what the boost pressure is except for its gain value where it actually opens the wastegate and activates the solenoid. For example if you set it to open the gate at 20psi, then that is where it opens and starts pulsing the solenoid (PWM Frequency) at whatever value you set it at. It doesn't deviate from that gain value regardless of what pressure it's at.

So more load = more boost on large turbo setups unless you turn down the boost controller in the next gear. If the engine has enough time/pressure to really get the turbo lit, then it becomes less of an issue. The dynojet software outright says it doesn't matter what gear ratio your car has.

In addition Dynojets are interia dynos. They read power as a function of the roller mass being moved. So if the roller weighs X amount (this is hard coded into the software based on the drum itself) and it accelorates at this amount, it required this much power to do so. Higher gear just means that it acelerated slower, but at a higher overall speed.

Also, engine RPM is derived from an electronic pickup method, not a "roll on" like dynocoms, superflo, dynodynamics or mustang dynos. Those require more precise configuration when not using a pickup to determine RPM....but that is a tangent.

So back to the dynojet.... torque = horsepower X 5252 / engine RPM (from pickup).....it won't even show torque if you don't have the engine rpm signal, just HP. Why? Because the dyno needs it to determine the gear reduction found between the engine itself and the roller.