To tune or not

Ape Factory

My experience was an overly rich a/f ratio with two mods, intake and HFC's. So much so I felt like I needed to tune. My dyno was nothing extraordinary but it did show my a/f ratio in the low 10's, even high 9's.

The results after tuning are a noticeable midrange and top end punch that I didn't have before. I could feel the engine falling on it's face above 5500 rpm due to the air fuel ratio. I haven't strapped it to a dyno yet with the tune but the traction light will come on in the first four gears (7AT) under hard acceleration.

On gas mileage...when you're cruising on the highway, you're in open loop and the ECU is taking feedback from the 02 sensors. It has a target A/F ratio it shoots for (stoich usually) so a "tune" won't affect that. What WILL affect your mileage, and I experienced this first hand, is the throttle hijack and the amount of time you spend hooning the car at WOT with your new power. But seriously, the more aggressive throttle does take it's toll on mileage, especially around town. It is better from a dig (stop) but I don't always like it coming out of a corner or when rolling slowly and then accelerating.

Personally, I like a more progressive throttle and I have two throttle maps, both more aggressive than stock. One is moderate, one is highly aggressive. I'm actually going to lower the moderate to minimal. I'd rather have a more linear ramp up to WOT, especially when it's wet out.

The other benefit to ECUtek is timing control and performance traction control which is better than the VDC system. If it's really nasty out, I'll use VDC.

I also noticed the throttle hijack screws with the transmission's shift logic on the 7AT. I actually liked the 7AT but I also knew how to drive and program it (it's adaptable) to my driving style. The hijack sort of ruins that magic and it can hunt for gears a lot more when not going all out.

And don't forget to have them up the line pressure on your tranny if you have the 7AT. I have a mild bump and the actual shifts are more firm and faster than stock. It won't change the time from clicking the shift paddle to the time it starts to shift but it'll shorten the actual shift time. Doesn't seem to upset the stability of the car. If you have a manual, just ignore this portion.

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'13 Audi RS5 Misano w/mods-The Red Mist
'13 G37 IPL-SOLD