I roadrace with the SCCA with a tube frame 2009 MX-5 Miata powered by a 12A. My last racecar was a Suzuki Swift with a 1300 twin cam with Megasquirt FI using a 3.57 box.

I'm converting the Mazda from a 48 IDA to a throttlebody. I live at 8700 feet altitude and race anywhere from Texas to the midwest. At this time I'm planning to only use the Megasquirt for the fuel and leaving the distributor for the spark. At some point I will convert the spark, but right now it's a time issue.

I bought all my parts and pieces from DIYautotune.

For the Rotary what box should I get?

PCB2.2

PCB3.0

PCB3.57

I do plan on using the relay board and connect cable with this build.

Will I have to make any mods in the box to control just fuel?

Will I need to connect only the neg coil lead to the relay board for a trigger signal.

Thanks

 

I typically get PCB3.0. It's much better than the 2.2 and cheaper than the 3.57 but you do have to build it yourself to get the cheaper price.

most likely you'll need a resistor inline from the coil negative to the MS but probably nothing else.

If you're using the distributor that should be all you need.

Ken

 

Thanks Ken.

I'm going with the prebuilt unit, I don't have the confidence in my soldering yet.

I found this in one of the work sheets I downloaded, is this what I need for the neg from the coil to the relay board?

Thanks

 

That's the one.

Ken