MR2 Owners Club

Hey all, I've been keeping this one quiet in case my grand plan turned out to be a lemon but.... today I finally managed to get everything syncing up and working with my carputer on the test bench.

This has been a massive undertaking and has required learning 3 new programming languages and countless hours of trawling through forums for the best solution.

MR2Duino is a fully featured EBC/Launch/IC Mist controller that is controlled from a flashAS3 frontend that is embedded in Centrafuse 4.

it uses exactly the same (if not better) PID algorithm as the top EBC's ,
defult state is N/O which means in the event of a solenoid failure the car will revert to stock boost, this setup also means that instead of bleeding air away from the wastegate it stops it all together, after lots of research this will increase spoolup as once the solenoid is energised the wastegate will not even partially open untill the PID becomes active
Fully closed loop operation
2 map sensors which average and throw up errors if they are mismatched by x amount,
it has multiple error checking including a last resort ignition cut for 2 seconds if it exceeds a set level for x milliseconds (to deal with spikes)
there is also a hard wired boost microswitch that will activate the cars own fuelcut in the event of an arduino failure.

The launch control works on exactly the same PID system but instead of bleeding air it interrupts the feed to the ignition coil,

all of this is running at a sample rate of 100Hz

mist is simply a button for a relay at the moment but will be incorporated with an IAT sensor for automatic soaking

In development:
Gear dependent boost scramble,
Flatshift with continuous turbo spooling,
Wheelspin/Traction control from launch (if it detects the abs sensors are rising faster than the speedo it will retard the ignition untill grip is regained.


every test I've run including using a large compressor the end result has been a solid hold with practically no drift and easily making the most of the 33Hz MAC solenoid.

I'm not quite ready to release any code yet but I have some pics of the flash front end.
The interface is still very much in development and is by no means the final design

this project has so far cost me less than £40 (apart from the car pc bit) and I'm anticipating a final cost of less that £70 with all the relays/mosfetts

I like the look of this could use the inter cooler spray as a water meth spray controller?

Absolutely, you'd probably want a separate arduino nano or something triggered by the main one as you'd need more error checking and a rock solid failsafe, wouldn't want the pump stuck pumping water into the engine! Maybe a 3 way solenoid before the injector that when closed purges the built up pressure back into the tank and waits for pressure to build up before pulsing the injector. Anything is possible with these things, the next phase of my project is digital hvac controls so I can replace the heater unit with a head unit with rear aux in for the car pc.

Seriously impressive mate, been wanting everything to be centrally controlled on my 2 via a touchscreen carputer, although I wouldn't know where to start.

well done with this project as i know from experiance that what you have done so far is a huge amount of work.

Iv'e canned the boost/launch control aspects of this project in favour of a gizmo ms2 & WOTbox, I had a few failures on the bench and whilst i've ironed most of the kinks out I'm not happy to risk my freshly rebuilt CT26/Engine.

I'll still be using the arduino in the car to run the heaters and manage the intercooler misting so this is what i'll be concentrating on in this thread. the full project / source code can be found on my website (eventually) but i'll use this thread to keep people updated and maybe inspire some people!

so here's the design I've settled on for the heater controls: I've taken the symbols from the stock controls and tried to keep a 90's feel whilst making it easy to use on a touchscreen.

everytime a setting is changed it is stored in non volatile memory which is read on boot up and then sent to the car-pc to sync the settings. the serial string for setting the Arduino is sent at every button press so i'm not constantly spamming the serial line.

the Intercooler misters will be handled in a popup screen when i get round to it!

Quick question: As far as I know there are 2 types of heater controls, am I to assume that this will only work with one type?

Protok wrote:Quick question: As far as I know there are 2 types of heater controls, am I to assume that this will only work with one type?

There's a physical component to the UK mkII controls, if that's what you're referring to?

Subscribed for updates, how-to's & kits for sale lol!

shinny wrote:

Protok wrote:Quick question: As far as I know there are 2 types of heater controls, am I to assume that this will only work with one type?

There's a physical component to the UK mkII controls, if that's what you're referring to?

I always thought it was the aircon vs non aircon. But effectively yes.
I cannot imagine this being able to work with the non aircon controls or am I wrong?

I am hoping I am wrong cause I really don't want to have to retro fit aircon controls.

There is no reason that the pwm for the jdm air con version couldn't be swapped for a beefy servo, it's not an endgame :-)

Marc2Turbo wrote:There is no reason that the pwm for the jdm air con version couldn't be swapped for a beefy servo, it's not an endgame :-)

Indeed!

Protok, the aircon unit is on a seperate plug, so that's no issue. Imports have an auto setting that the UK cars don't, but again not exactly a show stopper

shinny wrote:

Marc2Turbo wrote:There is no reason that the pwm for the jdm air con version couldn't be swapped for a beefy servo, it's not an endgame :-)

Indeed!

Protok, the aircon unit is on a seperate plug, so that's no issue. Imports have an auto setting that the UK cars don't, but again not exactly a show stopper

Good to hear

I'm sacking off the air con completely but it wouldn't be an issue to add 2 more relays and buttons, the donkey work is done now, it's just cut and pasting code for new additions