Re: Dyno Test (archive)

The dyno test cost me $35 for each run.
Here are the results assumimg a 0.74 drive train efficiency conversion factor between wheels and motor. I also included info from the Dinan website on what my car should have before the exhaust addition. DYNO #1 is before Sports Mufflers and Dyno #2 is after. I hope this table keeps its form and doesn't becone screwed up once I submit.
RPM Dinan HP DYNO #1 HP DYNO #2 HP
3500 232 230 236
4000 256 254 271
4500 283 285 301
5000 291 291 303
5500 300 300 316
5700 301 301 317
6000 292 286 297
RPM Dinan Torque DYNO #1 Torque DYNO #2 Torque
3500 348 350 365
4000 336 338 353
4500 330 325 338
5000 306 303 318
5500 287 286 302
5700 277 275 281
6000 255 246 260

As you can see, my car, before the exhaust mods, followed the Dinan curves (for Stage 2 software and CAI) very well except at 6000 RPM. It it also clear to see that addition of a sports muffler makes a difference. The mufflers used on the 740s must restict the exhuast a great deal. Makes sense since the majority of 740s are sold to older people and they would want a very quiet car. They especially restrict power at the low and middle ranges. I guess the rason that power is not improved as much in the high RPM is that the limiting factor at this point with greater flow volumes of exhaust gases is the exhuast manifold, not the mufflers (by the way I left the resonator on).However I did pay a penalty in that now I can hear the muffler when I hit the accelerator. It is about as loud in the rear as my CAI is in the front.

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