Thread: 07 wrx tune
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Old 05-12-2012, 10:17 AM
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Quote:
Originally Posted by RedMY01Owen View Post
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.
Ok, because we are talking about being on a dyno, I and others have assumed you are referring to launching and clutch stuff on a dyno.

The way the torque curve comes on and tapers off will determine the drive ability of the car. Regardless of dyno conditions, ramp rates blah blah, the way the torque curve behaves tells you instantly how that car will drive on the road in any rpm, gear, flux capacitor etc. The shape of that curve shows you more than any peak figure can tell you. And we are back to area under the curve...

Anyhoo, interesting discussion. It will be good to see the full graphs of this run to actually see what is going on.
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