GI: "YarGauge" replacement clock module (Digital Tach, etc.)

[CTScott]

So, I had Crashy's ECM fired up on my bench today as I was getting tired of having to go from my office to the garage to do some testing. I built a couple of circuits to make sensor data inputs to the ECM change, so I could vary the data (Speed, RPM, and Coolant Temp).

After successfully fooling the ECM with the 3 circuits, I realized that the speed one could be a fairly simple way of bypassing the speed limiter. Does anyone who races (legally) have an interest in testing that functionality?

[Altitude]

Originally Posted by CTScott

So, I had Crashy's ECM fired up on my bench today as I was getting tired of having to go from my office to the garage to do some testing. I built a couple of circuits to make sensor data inputs to the ECM change, so I could vary the data (Speed, RPM, and Coolant Temp).

After successfully fooling the ECM with the 3 circuits, I realized that the speed one could be a fairly simple way of bypassing the speed limiter. Does anyone who races (legally) have an interest in testing that functionality?

It's a good thing you're not a evil genius... or are you?

[CTScott]

Originally Posted by Altitude

It's a good thing you're not a evil genius... or are you?

Evil - Definitely evil.

[justjesus]

Originally Posted by CTScott

After successfully fooling the ECM with the 3 circuits, I realized that the speed one could be a fairly simple way of bypassing the speed limiter. Does anyone who races (legally) have an interest in testing that functionality?

I wouldn't mind taking another trip to El Mirage for top speed runs (it's legal).

[CTScott]

Originally Posted by justjesus

I wouldn't mind taking another trip to El Mirage for top speed runs (it's legal).

Cool! When I have a chance I'll build up a test unit. I realized recently that I can do a reverse test initially to make sure it works. By reverse test I mean fooling the ECM to think that the car is doing 130MPH when it is actually only doing 25.

[justjesus]

Originally Posted by CTScott

Cool! When I have a chance I'll build up a test unit. I realized recently that I can do a reverse test initially to make sure it works. By reverse test I mean fooling the ECM to think that the car is doing 130MPH when it is actually only doing 25.

LMAO - I was thinking you'd be driving in reverse!! Glad you cleared that up.

[CTScott]

Update: Getting close!

I am making good progress on the YarGauge development and am getting close to being ready to cut a production printed circuit board that will allow me to package it to fit where it is intended to go. Right now I have three separate prototype circuit boards, tied together, handling the various functions.

On of the last "data" related pieces I have been working on is the fuel economy (MPG) piece. Last night I did a test run to make sure that my code was functioning properly and captured the data to do some after the fact analysis on. Here's a plot of speed (MPH) vs. fuel economy (MPG) from a 4 mile test run last night. The graph really doesn't have much to do with the YarGauge, but I thought it was interesting enough to post.

I started capturing data about 1/4 mile from my house, going down a long steep hill, as I was specifically interested in catching a DFCO event.

Then I sit at a stop sign for a minute or so, waiting to make a left. Then, I drive about half a mile before making a left, a quick right, and a left (the three low bumps). Then I cruise up a long hill, which has a couple of level off points (seen by the DFCO events). I then make a rolling stop (low bump towards the end), a right turn, and then cruise down a gently sloping hill, before finally stopping.

MPG vs MPH.jpg