Hi guys, this is Paul L. from Yimi Sport Tuning. I dynoed ZooZoom's car as well as a bunch of others this past Saturday. We usually deal with Subaru's and Evo's, but since I'm actually a former Mazda6 owner, so I figured I check in here.
Anyways, ZooZoom's car was certainly very impressive. I really cannot explain why his car did as well as it did on the first 2 runs. 255-260 whp and 300wtq was well beyond what I would have expected to see out of that car. A typical stock Evo or STi puts down about 245whp on our Dynojet, so for ZooZoom's car to exceed that with nothing more than a TMIC upgrade was very surprising. The car was warmed up prior to the run to get the fluids up to temperature, and we sprayed down the TMIC and radiator with water to help keep them as cool as possible during the run. I made all the runs in 4th gear and with the hood closed. I will note as ZooZoom did, that the 3rd run (done after a 5 minute cool down with the engine off) dropped off significantly in both whp and wtq. Torque in particular fell off pretty dramatically.
If I were a betting man, I'd say that the operating conditions for the first 2 runs were optimal for the ECU to supply all the timing advance and boost allowed in the maps. The subsequent runs probably had coolant temps and/or air intake temps higher than a threshold point where the correction tables in the ECU calls for boost and/or timing to be pulled. Judging from the big loss of torque we saw on later runs, I'd say that the ECU trimmed back the wastegate duty cycles to reduce the amount of boost. I did also put my hand on the ETS TMIC after the last run, as I was wondering if the IC was heatsoaked and remarkably the portion closest to the throttle body was still cool to the touch, so I don't think that high manifold air charge temps (and the usual resultant detonation/timing pulls) caused the reduction in power on the last runs.
One last note that I feel should be addressed is that by nature Dynojets are pretty dang consistent from unit to unit. They calculate power from acceleration of a known mass (the rollers). There are no user definable variables such as you will find on a Mustang dyno, Dynapak, Dyno Dynamics or other dynos out there. What you see is what you get. The only correction factors are the different worldwide industry standards. We use SAE and it compensates for temperature, elevation and humidity differences. In the case of ZooZoom's car, I believe it added 5% to his numbers due to the ambient temps being 100* and the shop being at 1000ft above sea level. Of that 5%, 1% is due to elevation and the other 4% was for the ambient temp.
I'm headed to the shop now, so I'm going to pull the runfiles and the jpg's from all the runs from the dyno computer and send them over to ZooZoom.
