If I understand correctly, torque curves are usually measured at constant, wide open throttle. However, the engine tester can be run with a variable throttle. If this is true, then shouldn’t the transient response be lower at part throttle? For instance, the automatic tester has a gradually increasing throttle, so the engine torque should start out much lower than the torque curve and then increase over time to match the curve. Is this correct?
On a similar note, how is the turbocharger spool simulated? I know that turbos will spool faster if you start at a higher RPM. Are they assumed to start spooling from idle? What if you are at partial throttle?
I understand if this may be needlessly complex, but I am genuinely curious as to how much power my engine makes under varying conditions. We always see engine performance reported at maximum conditions, when in fact they are rarely within those conditions.
All tests are run at full throttle, always. The “throttle” is not really a throttle but rather an RPM control. The only time we simulate partial throttle is in the economy calculations, where throttle position comes with an efficiency penalty for low throttle during cruise.