The GOODbox
07-10-2019, 03:16 PM
#551
Registered
What's up, guys? Thought I would share here a little something I cooked up recently that may prove interesting for anyone with a GOODbox and a boosted RX-8.
It's a small adapter circuit board that replaces the on-board boost pressure sensor such that an external, remotely-mounted off-the-shelf GM 3 Bar MAP sensor can be used instead. So instead of having to run a vacuum hose all the way from the engine bay to the GOODbox, just wires can be ran instead. The on-board sensor is de-soldered and this board is soldered on in its place using pin headers (the 6 holes match the pin-out of the on-board sensor). Wiring to the external MAP sensor is soldered to the three labelled points on the opposite side (like the GOODbox's Aux inputs).
The output of the GM MAP sensor is scaled to match that of the old on-board MPX4250A sensor as closely as possible. It should be within 1% across the pressure range. Note that it doesn't magically allow boost readings of 3 Bar just because the GM sensor goes that high! It will still only read up to 2.5 Bar, as it has to match the output of the old sensor (which goes to 250kPa, or 2.5 Bar) so that the GOODbox firmware can interpret the reading correctly.
Also, because the signals and power for the boost sensor are now going off-board, the adapter also features some protection for the 5V reference output. Current output is limited to approx. 60 mA in case of short-circuit to ground (or maybe faulty sensor). The 5V line is also protected from over-voltage (e.g. short to 12V), and will be automatically cut off if an over-voltage condition is detected. So nothing should blow up in case of wiring fault or incorrect connection.
Attached here are a circuit schematic PDF and PCB manufacturing files (Gerbers) in case anyone wants to make one themselves.
It's a small adapter circuit board that replaces the on-board boost pressure sensor such that an external, remotely-mounted off-the-shelf GM 3 Bar MAP sensor can be used instead. So instead of having to run a vacuum hose all the way from the engine bay to the GOODbox, just wires can be ran instead. The on-board sensor is de-soldered and this board is soldered on in its place using pin headers (the 6 holes match the pin-out of the on-board sensor). Wiring to the external MAP sensor is soldered to the three labelled points on the opposite side (like the GOODbox's Aux inputs).
The output of the GM MAP sensor is scaled to match that of the old on-board MPX4250A sensor as closely as possible. It should be within 1% across the pressure range. Note that it doesn't magically allow boost readings of 3 Bar just because the GM sensor goes that high! It will still only read up to 2.5 Bar, as it has to match the output of the old sensor (which goes to 250kPa, or 2.5 Bar) so that the GOODbox firmware can interpret the reading correctly.
Also, because the signals and power for the boost sensor are now going off-board, the adapter also features some protection for the 5V reference output. Current output is limited to approx. 60 mA in case of short-circuit to ground (or maybe faulty sensor). The 5V line is also protected from over-voltage (e.g. short to 12V), and will be automatically cut off if an over-voltage condition is detected. So nothing should blow up in case of wiring fault or incorrect connection.
Attached here are a circuit schematic PDF and PCB manufacturing files (Gerbers) in case anyone wants to make one themselves.
08-26-2021, 09:16 AM
#554
Registered
I have done something similar, instead my kit will turn the gauges inside the cluster into real gauges with proportional readings.
See https://www.rx8club.com/series-i-int...er-kit-272973/ for details.
See https://www.rx8club.com/series-i-int...er-kit-272973/ for details.
10-06-2023, 09:54 PM
#557
get with the times, he’s a forum member here:
https://www.rotarytronics.com/index....uickSearch=rx8
https://www.rx8club.com/series-i-int...er-kit-272973/
.
https://www.rotarytronics.com/index....uickSearch=rx8
https://www.rx8club.com/series-i-int...er-kit-272973/
.
The following users liked this post:
zoom44 (10-07-2023)
10-10-2023, 01:47 PM
#560
If someone is interested in taking this on I'm open to a chat. I did purchase all the designs and rights from Pieter and would love to see more of these out in the wild as I have them in all my 8s and my Speed3 and they're great.
I have boards built up (~50) for the Speed3 as well which was never launched. The batch of RX8 boards I believe are just missing the pressure sensor but otherwise good to go. I'm short on housings/harnesses but can provide everything I have if someone wants to take the time I don't have anymore to pursue this. I refocused into the bolt-in REW swap kits as they are less work and more useful for me and the community so that's where my attention is at. You can reach me here or at https://www.goodboxmotorsports.com/
I have boards built up (~50) for the Speed3 as well which was never launched. The batch of RX8 boards I believe are just missing the pressure sensor but otherwise good to go. I'm short on housings/harnesses but can provide everything I have if someone wants to take the time I don't have anymore to pursue this. I refocused into the bolt-in REW swap kits as they are less work and more useful for me and the community so that's where my attention is at. You can reach me here or at https://www.goodboxmotorsports.com/
10-15-2023, 02:24 PM
#561
Registered
Well, I fail to see why this design would ever resurface... because on that red dot matrix screen you may barely cram 2 gauges. I can understand how it came to be and how it was nice for its age. But now... well... it seems dated to me.
10-15-2023, 04:34 PM
#562
It can display 2 metrics at a time, but you have 4 pages x2. I love mine, it let's me keep the interior stock, and not have to carry a separate reader. Especially on track, having a digital temperature readout is great.
Don't knock it till you've tried it.
Don't knock it till you've tried it.
The following users liked this post:
dondo (10-16-2023)
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