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Auto-Blip, down-shift rev-matching

My CPU appears to have limited processing power, spending too much time to complete a successful rev-matched down-shift while braking at the same time. The end result is that I brake too much and too late, burning off too much speed. As my CPU is a one-off special edition that can't be easily upgraded, I decided to help it with a co-processor - the Auto-Blip Intelligent downshifter.

After a quick test drive after installation, I conclude that two brains works better than one. I can now focus on driving the car, while the Auto-blip handles the rev-matching. The ever so difficult downshift to 2. gear is now a breeze.

Designed to fit in that spot?

The Auto-Blip kicks into action when you brake and clutch simultaneously, blipping the throttle at a configurable delay. The amount of throttle blip (how much the revs increase) is also configurable.

I did have some issues getting the unit to work in my C5Z. The manual states to only connect two off the APP sensors (throttle position sensors) on the throttle pedal. The C5, however, has three sensors. As a failsafe, the ECU performs continuous comparisons of the three sensors, and if there is a deviation the throttle pedal is disabled and you get a CHECK ENGINE light and a bunch of OBDII error codes.

To my luck, it seems that I have received a specific version of the Auto-Blip modified to be compatible with the C5. It has the an additional app sensor wire (brown) that is to be connected to the APP Sensor 1. After connecting all three wires and performing a calibration, everything was ok.

I also learned that the 12V and GND connections needs to be connected to the documented OBDII port pins. Connecting it to random 12V and/or GND sources produced error codes, one can only assume that this is because the Auto-Blip is modifying a signal going to the ECU, and a measurement/value is only valid if all the interconnected systems are at the same voltage potential.

I had the Auto-Blip installed prior to this track day. The throttle blip on downshifts are handled by the Auto-Blip. It only took a few laps to tune in the delay and throttle settings. When tuned right, you can feel the downshift going smoother through the gear lever. Failed throttle blips with the rear wheels locking up, causing the car to loose rear grip, is also eliminated.

I highly recommend the Auto-Blip unit!