Additional sensors for Motorsport?
 

Planning out a new ECU install. Car is track only. What sensors are needed for motorsport, and the most reliable way to implement them? I would like to (aim to) wire everything in one go rather than it evolve over time (yes I know it probably will). ECU is a DIY MsPnP.My short list at this stage

- Coolant Temperature. Is OE sensor sufficient?

- Oil Pressure. Is sandwich plate best? Any downsides?- Oil Temperature. Ideally measured in sump, but will probably measure from same sandwich plate as for oil pressure

- Flex Fuel Sensor

- WBO2

- GM IAT

- Fuel Pressure. Will add a test / drain port at same time.

Will be some sort of display dash.Reliability is king to me in motorsport. Are any of the above adding more risks than potential problems they will solve I’d consider leave it out. What have I missed?

IME you want the oil pressure sensor remote mounted on the firewall to keep it from getting damaged by vibration. Picking up the remote line from the sandwich plate is probably fine though.

OE coolant is fine. Oil temp I'd want two sensors, one in the sump, one in the outlet from the cooler.

You're missing a data system with brake pressure and steering angle sensors. Send it everything else via CAN bus from the ECU.

--Ian

Cheers Ian.

I started typing wire for later addition of brake pressure sensor in the earlier post but honestly not in the short term plan

Oil temp
Oil pressure


You will have very few moments to look at your gauges when driving on track. Typically only at the beginning of straights.
Coolant temp is somewhat redundant if you know oil temp, and oil temperature is more critical. For motorsport I wouldn't add any more gauges than that because in Motorsport you're trying to reduce possible failure points. You don't need a flex fuel sensor for Motorsport because you know what fuel you put in the car. You don't need a fuel pressure sensor because you don't need an additional point of failure on your fuel line and if the fuel pressure has problems you will feel it immediately and/or it is too late to do anything about it. I like gauges with warning lights for oil pressure and temperature to alert you of a problem when you are otherwise occupied driving.

For diagnostic purposes if there's a problem and for tuning it's certainly nice to have a few more gauges, but temperature, oil pressure, fuel tank level, and a tachometer are all you really need. I still have the stock coolant temperature gauge hooked up but I find it to be mostly useless because of it's vagueness and lack of a warning light or alarm.

Gauges are useless, there's no time to look at them and mounting them is a pain in the butt. The better model is to plug all of these sensors into a display/data logging system that's configurable in terms of what goes where and has warning lights that it can turn on when certain values go beyond certain configurable thresholds. Then you map lights to actions, something like: yellow means "back off for a lap", orange means "slow way down and pit", and red means "stop the car as soon as it's safe to do so".

I disagree on fuel pressure, I have a sensor in my car and have used it to diagnose and fix two significant issues. Again though, it was useful in a logging & data analysis context, not as a live-view gauge.

--Ian

What Cordus said. Feed sensors to ECU, program a big ass warning light(s) to come on under certain conditions, and that's all. Less is more.

Agreed with others, necessary Motorsports sensors are the one's listed already, and warning lights are better than gauges. Our FSAE car had literally one light in the center of the dash, that was the only interface. No tach, no gauges, no driver distractions, just a light that would tell the driver to stop driving (if it was autocross), or ease up (in endurance). Everyone complained about not having a tach, until we added it and none of our drivers paid attention to it.

There's also the sensors that can help make you faster. These are only worth it if you have a plan on how to use them. Don't just add brake pressure sensors because brakes are important. Add brake pressure sensors if you're trying to validate your brake spreadsheet and you will actually use this data to make a change to the vehicle. Or if you are trying to train your leg to reach lockup force faster and you want to plot pressure versus time. It happens ALL the time at work (professional Motorsports and Engineering services company) that extensive instrumentation is "needed", a ton of cost and complication gets built into the project, then the data just sits in a repository for years. Say you add a gyro sensor because it's a critical measurement in Motorsports. Now you know that at a certain 45mph corner your car yaws at 25 deg/s. Will you actually tune your suspension to increase yaw? Is this already too much yaw? Could you have just used lap times or GPS plots (like am AIM Solo) to determine if the change(s) were beneficial?

Which Megasquirt do you have? There are 3 different MsPnP's. Most of them will already be running close to max inputs with the necessities. Most Megasquirts don't have a bunch of extra inputs and need a CAN box to provide more. Something you can also do is wire each analog input to a 3 pin electrical connector, and just have 5V, ground, and signal for each. Then there's no splicing or modifying when you want to add a sensor, and if you don't have enough inputs, you can unplug what you aren't using in a test session, and plug in what you are.

Totally agree with other posters here regarding gauges.

You see a lot of cars with specific gauges scattered throughout the cabin but unless they're directly in the line of sight of where you're driving at the track, you can't risk looking down at them and take the time to actually read them - you're never going to be constantly reading a gauge anyway - you'll crash!

Warning lights immediately in the field of view are much better in this situation, you'll notice them without needing to focus explicitly on them.

Ideally you want to log the gauge data and synch it with your other track data for post-analysis, when you'll have plenty of time to analyse the data.
If you can't log the gauge data, you should at least buy gauges that have a peak recall function so that you can see what it was after a track session
Gauges that don't support one of the two features above are for "Wank/Show value" only, they're not practical.

I've wasted a LOT of time and money on gauges that just sucked practicality/usability-wise and after playing around with Arduinos, ended up designing my own board for an Arduino Teensy that outputs multiple gauge values to 2x OLED displays (mounted in the Fuel and CLT instrument panel spots) and sends the data to the MS via CAN:

Version 1.0:
https://cimg6.ibsrv.net/gimg/www.mia...45b3f85cf6.jpg
The board uses an Arduino Teensy 3.2, 3-axis Gyro daughter board and CAN MCP2551 IC.
I originally intended to use 90* headers but when I assembled it, I was missing the 2x 6-pin 90* headers so used vertical ones instead (for consistency)

Top Connectors:
* 3x 2-pin digital inputs (one used for control of OLED displays)
* Innovate Wideband O2 serial port (should have been a 4-pin connector since I also need a 5V source - I used/stole a 5V pin from one of the Digital inputs)
* 5V/GND power source
* 4-pin GPS serial port
* 2-pin CAN connector

Bottom Connectors:
* 2-pin Fuel Level sender
* 4-pin OLED connector (this supports the 2x OLED displays)
* 3x 2-pin temperature sensors (one for Oil temperature)
* 1x 3-pin pressure sensor (used for Oil pressure)

The individual connectors are too fiddly/delicate for a track car so I'm now redesigning this board with a single automotive connector (when I find one that I'm happy with) to simplify wiring and have added another pressure input (for fuel).

https://cimg5.ibsrv.net/gimg/www.mia...99d3c179d8.jpg
When I get time, I need to make 3D-printed housings for the OLEDs that can just be screwed in place (for now, the red mounting panels simply screw onto the OEM gauges via their two small pins that hold the gauge faces in place and the indicator needles have been removed).


https://cimg8.ibsrv.net/gimg/www.mia...22f02f1161.jpg

Pushbutton to control OLED display and reset Peak values (single press cycles 3 Lines -> 4 Lines -> Peaks, long press re-sets Peak values)



https://cimg7.ibsrv.net/gimg/www.mia...fd35c8f294.jpg
3 Sensor values per OLED

https://cimg0.ibsrv.net/gimg/www.mia...aff6d37e42.jpg
4 Sensor values per OLED (smaller font than above)
MUCH more elegant/simpler/practical than scattering an extra 6 gauges throughout the cabin!

https://cimg4.ibsrv.net/gimg/www.mia...0481346327.jpg
Peak value display (the other, Right side, OLED displays 4 Peak Sensor values)Note: Peak values shown here are after a Reset (which is why they're all zero)

Hi,

Appreciate the replies, but I never mentioned adding any gauges at all. As mentioned in my first post I will use some sort of display dash. Question was what sensors for motorsport. Warnings will either display on the dash or output to a single (bright, can't be missed) warning light.

Seems like fuel pressure is kinda debatable. & Yes Codrus, useful more so from a logging / fault finding point of view.

Arduino project looks cool, but won't be me.

Cheers.

This looks interesting. Sub'd