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Dyno 2001-10-19

Here is my October 12, 2001 dyno run. This was generated as part of my tuning session at XS Engineering. I must say that although I did not hit the target number I was going for, this was a good experience. XS really knows how to tune these cars, and that is a pretty rare find. I look forward to having them do some more tuning work for me after I get some issues sorted out.

I was shooting for 400 rear wheel HP (RWHP) at 15 psi, but it didn't happen. I think the biggest factor was that my boost control setup was not working as I hoped it would. I have the PowerFC controlling the stock wastegate solenoid, which is now connected to the external wastegate. This doesn't work very well, or at least it doesn't work how I have it setup. Boost will rise to 15 psi, which is what I wanted, but it quickly falls to 13 psi after that. Peak HP is probably the same as I would get running 13 psi across the board, but torque is probably what I'd get running a solid 15 psi. 

My intake temps were high, too, which made it hard to get in some good power runs. It also made the car prone to detonation, which is the main enemy of turbo rotaries. I added a fan to my Medium intercooler, but I don't have the wiring quite right, so it wasn't working for the first few dyno sessions. Eventually, XS just wired it to stay on for the testing, and it helped keep the temps from rising too high, but they were still pretty hot. Stock-mount ICs are apparently not all that great for dyno work because they just soak up the radiator heat. My old Racing Beat dual tip exhaust was also probably limiting power somewhat, but after testing a lot of loud cars, XS seemed pretty fond of it. ;-) I think I will keep it unless it seems to be choking the power too much when I go back for a second round of tuning. I would probably replace it with the new Racing Beat dual-tip cat-back, the M2 dual-tip, or make my own with a Borla XR-1 Race muffler. I've got one of these Borla mufflers to weld into the center section, and I am hoping that it will make the car even quieter.

It was only making about 340 RWHP when I brought it in, and XS got it up to 367 RWHP / 302 RWTQ. I don't know if these are corrected or not, but I suspect that they are with the "SAE" labels. Here are the runs:




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