The reason your torque never peaked then dropped off is because he started the pull well after your torque peak (likely around 2500-2800rpm). The HP should have peaked at about 4000-4500rpm but obviously it did not.
Ok, that is what I was thinking.
I can't tell that its against the knock sensor but a jagged and early peaking HP curve is typical of that condition. It could also be a factor of the EEC pulling timing due to heat. If they had to hold rpms at 3000 for awhile to get a tach setup then that alone could have created excess heat. If you have an OD pulley on the blower and a stock IC it takes very little to overheat the intake charge and lose dramatic amounts of power.
Ok, if it the EEC will pull timing, that's probably what was happening. It probably was heat-soaked, so that's that. I do not have a OD pulley on it, either, because of this very reason.
I assumed from your 1/4 mile slip that you did a simulated 1/4. Mustang dyno's can do this and some people get a kick out of doing it so I assumed you had. However, a 1/4 mile simulation takes at least 15 seconds of continuous WOT on the dyno which, without air moving (and no the fans are not good enough as they only simulate about 10mph) could be disasterous to an SC motor. If you did not do this then forget my comments about he 1/4 mile simulation.
Yes, I did do a simulated 1/4. When you said simulated dyno run, you threw me off.
It was fun, and knowing what I do now, I will never do that again. Thanks for letting me know, I really had no idea.
"Real world" dyno numbers are fine for tuning but they do nothing to help a person gauge how well his car may or may not be doing compared to others. Call it internet bragging if you want, but without comparing his numbers to other SC's he can't even guess how well his car is or isn't running compared to other similarly modded SC's. I would suggest that for interest and comparison sake, people seek out dyno jets. You will get numbers there that look more familiar to you and make a lot more sense when comparing results with others on SCCOA and other internet sites.
I understand. What you are saying makes sense, but unfortunately, there are no Dyno Jets around here.
As much as some people like to bash dynojet numbers, I have found they are more easily translated to real 1/4 mile time. Give me a dynojet number and I can typically give you a very close to accurate estimated 1/4 mile time. Give me a possibly low balled Mustang dyno number and who knows? The Mustang dyno by me reads very close to dyno jet #'s, usually within 2-4%. Others not so. It has a lot to do with how the dyno is set up, calibrated, and used.
Do you do your tuning on a Dyno jet? If so, what would a bone stock AOD SC make on it?
On SC's it is not abnormal to have a hard time getting a tach signal. Often times when you can't get a tach signal it is also indicative of a DIS that is going bad or other power/ground issues in the car. Not always, but often. So the fact that he had trouble getting the signal does not point to incompetence.
Yeah, that makes sense. What made no sense to me was that when he first put the clamp on it, it picked up the engine RPM, then he was never able to get it afterwards.
I didn't miss the part about transmission issues, but I assumed that with the AOD being in direct drive that it shouldn't be a problem in D, but I may be mistaken on that.
Yeah, it was in D, so the transmission probably didn't hold me back any for that very reason.
As Damon said, the biggest thing you can pull from the dyno session is that your AFR is safe and flat. Both are good things and make the $50 worth it for that reason alone. But yes, the HP and torque readings are probably junk - either that or your SC runs like crap. LOL!
Ok, well, I learned some valuable lessons here that also make it worth it, such as never doing a 1/4 mile sim with it. And, no, my SC runs fine, so I am going with the option of junk readings. And, actually, I talked to a guy that took his twin turbo mustang there, and he said they suck. He said that they dyno'd him at ~330HP, and around ~550TQ. That's way off, considering he only runs 5PSI.