Question regarding running di and pi together

Hi,

I've just joined as I have a Mazda 6 mps which I'm hoping to fit a standalone ecu.

The issue I have is, it's a direct injection engine and as far as I'm aware, no one makes larger replacement injectors for them.

My question is, are there ecu's out there that will run the 4 stock di injectors and 4 larger staged port injectors, along side using 100% methanol (we only have 99ron fuel at the pumps)?

Assuming there is, is this the best way to go, or would I be better off not using the di setup at all and just running 4 pi injectors and methanol?

Many thanks

Gouldy

Both setups are possible but they are not easy and practical. Getting rid of the di system means reengineering all the electronic system of the entire car, the oem ecu is linked to most of the systems of the car plus is possible that many of the oem sensors including trigger sensors are very difficult to match with a generic standalone ecu system .

I think there are ecus to work with the di and the pi system but they are very special ecus , take a look to the Motec M-150 ecu for the Toyota Gt86 , the Toyota Gt86 have di and pi like your car and Motec have a specific solution for this package. Its possible to build a solution for your car with a Motec ecu but it s not straightforward and its not practical to invest all the effort just for one car there is a lot of hardwire and software programming work apart from the normal tuning. take a look https://www.motec.com.au/Toyota862012FA20D/Toyota862012-Features/

I think a best solution is to find a piggyback system or an interface software that works with the oem ecu and let tune the oem ecu for your convenience , there are some systems out ther like unichip or ecutek and a lot more ,some better than others or better said some better supported than others... they are not so flexibles like standalone ecus but some times are the only solution.

The use of other fuel its going to be possible depending of the capabilities of the management and tuning software and system.....

Hi Julio,

Thanks for the reply. Yes reflashing the oe ecu and running a split second controller for the pi, is the usual route taken on this platform, but isn't without it's issues.

I'm planning on building a new harness to run the ecu, so not too worried about that side of it. It's the coding side I'll get stuck.

I'll take a good look at that Motec m150 thanks.

Unless your DI injectors are designed by the driven by normal injector drives (like the GT86 platform), you should look at the MoTeC M142 ECU as it can drive both DI and port injectors directly (basically the DI version of the M150).

Thanks David.

I have seen the M142 and seen its supports Other di and pi, but I wasn't sure if it was capable of running both together, or one or the other, if that makes sense.

Yes, the M142 can handle both DI and staged Saturated Port Injectors. MoTeC USA just announced a WRX PNP kit based on the 142 that features this.

You can get a reasonable increase in power by using a larger fuel pump, modified spill valve, and increased fuel pressure under high load. When this isn't enough, adding PI into the mix is a viable option. Right now the two ECUs that I'm aware of that can support this are the MoTeC M1 and Syvecs.

Thanks Andre.

Yeah I'm looking for more than double the power the di setup is capable of. I will take a careful look at what both have to offer.

Out of interest, would it just be easier to not use the oe di and just run a pi setup?