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A golden opportunity came up: Pete's Supra was ready for tuning, as were 4 other AEM-equipped cars, so being the big ballers that they are, they flew in Justin Nenni from Tuning Concepts, an AEM specialist, and booked a Mustang Dyno for the day. Pete offered to shave a couple of hours off his precious dyno time so I can get my AF adjusted at 18psi. I hurried to get the usual pre-dyno maintenance done, (thanks again Zeus for helping out in the middle of the night): boost leak test, compression test, spark plug inspection all checked out OK, I took a day off work and headed over to the dyno, gotta have your priorities in check, right? As soon as I arrived, I saw the RB-26 Silvia with disappointment on the face of the owner. His 500+ HP setup had shown less than 350HP on the dyno, the tuner reassured him that it wasn't the first time he sees a Mustang dyno generate ridiculously low numbers. In the meantime, I compared AF data from the tailpipe sniffer to that recorded from the wideband 02. The numbers were identical, relying only on the sniffer myself, I was reassured. A second Silvia with an RB-26 motor was also highly disappointed to see anorexic numbers, sub-400HP. These are cars that I've seen ravage asphalt, I have a hard time hanging with them. The numbers were off. Same story with Pete, Supras regularly put down over 800RWHP at 30psi with his setup, his number was in the 500's, so I wasn't expecting much from the Z. To top things off, the garage was not well aerated, it was getting extremely hot in there and exhaust gases were not well evacuated, not the best conditions to dyno a car. My first pull at 14psi showed 315HP, but more importantly, there was a HUGE cloud of black smoke at high RPM along with a leaner zone at around 4k RPM. Within a few pulls, the AF was flat and the clouds of smoke were gone. HP was dropping consistently. After 3 pulls at 14psi, the Greddy SMICs were literally boiling up, I couldn't hold my hand on them for more than a second. I second-guessed the concept of small SMICs versus the much larger FMICs that weren't even warm to the touch after several pulls with the other cars, then brushed away those thoughts as I sprayed cold water on my ICs in a futile effort to cool them down. My pulls with 94 Octane gas at 18psi gave almost the same results as those at 14psi (around 340 HP), indicating that the car was heat soaked and that oxygen in the garage was lacking. Either way, the car feels dead solid at 18psi, power comes on strong and acceleration is neck-snapping. The number is clearly off, I'll try to do some pulls on another dyno to show the offset. Here's the graph, comments are welcome:
_________________________________________________________________________________ Im n0t Sarcastic (Kenny): not to over do it, but you're certainly the source of high-class Z mods
ZEngineer24: what do you mean by that?
Im n0t Sarcastic: I just mean, your Z is one I really admire
"The Z is the cause and the solution to all my problems" -- Me
manstretch: well, my rear end is just worn out
ZEngineer24: sig quote 
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Better late then never: Dyno tuned Sports 500 Z - 
09:22:47 08/15/06
