Quote:
Originally Posted by Kato
I would be very concerned about a power run where the clutch is released at 2500rpm to generate maximum torque.
I would advise learning more of how a hubpack dyno works. With the ramp rate, the car will be in 4th gear and idling along under 2000rpm before the operator presses the accelerator. Clutch and starting a graph at 2500rpm just doesn't come into it.
A dyno plot should always start out low, build up to maximum and then taper off. Any graph that doesn't show these items must be questioned.
The shape and time to achieve maximum torque is the most valued part of the dyno graph. Not receiving this means you have very little information on what your car is doing.
Whilst you have said there is some information to show mid range and top end power, without the starting point it is meaningless.
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Obviously you wouldn't use the clutch to launch a car on a dyno, the sentence of mine that you quoted was referring to real world conditions. People are usually much more interested in how a car performs in the real world as opposed to a WOT power run from 2500rpm. As you say, the dyno will start at a given rpm, and ramp up at a certain rate, both of these parameters can be set by the operator to show many different scenarios.
I completely agree that a standard dyno plot will "start out low, build up to maximum and then taper off" but this isn't the only way that a dyno can be operated.
I would argue that "The shape and time to achieve maximum torque is the most valued part of the dyno graph" is slightly misleading and the dyno only really shows this for a single, abitrary ramp-rate. I really don't care what my car performs like when subjected to WOT from 2500rpm because I don't drive my car this way. I would be much more interested in how the car performs in the normally used rev range and how it spools up from say 4000rpm at WOT (simulating a down shift). Dynos are great, but people put far too much emphasis on the pretty picture they print out from a WOT run.
I'm not trying to attack anyone here, least of all you. I was originally just trying to help out the OP to extract some useful information from the dyno print-out. the dyno plot should be questioned, but not completely disregarded.