www.MSruns.com read only forum (Jan.15,2018)

Name: Dimitris Stasinopoulos

Vehicle: 2002 Mazda Miata/MX-5

Engine: 1.8lt, inline 4, 16v, VVT, 10:1 compression ratio

Injection: Port injection, alternating, 270cc injectors, stock manifold.

Description: Retrofitted a CAS from a '96 1.8 Miata - apparently you can't use the stock crank and cam sensors as they are incompatible, requiring many changes to the MS. I am using an external MAP sensor in the engine bay made from GM, I find it more convinient to route wires through the firewall than a vaccum hose. I am using the stock coolant and air temperature sensors. I measured the bias resistor in the stock ECU and based on the resistance/temperature plot of the said sensors (available in the Mazda service manual) I downloaded the proper sensor data using EasyTherm. For exhaust gas oxygen measurement, I got an LM-1 from Innovate Motorsports.

I generated a basic VE table using MegaTune, and once the car was warmed up using the stock ECU, I switched to MS and the idle was exactly as smooth as with the stock ECU - albeit a little too rich. At this point I am still tuning my air temperature correction and warmup settings, and things are looking great. Ignition and idle control (via a PWM idle control solenoid) are still left to the stock ECU, however I will also do ignition as soon as I am satisfied with my injection tuning.

I have an incar PC so I am able to checkout all running parameters without carrying a laptop with me all the time.

Obligatory pictures:

Update:

Got the ignition going today, as per the diyatotune.com instructions or 90-97 cars:

http://www.diyautotune.com/tech_article ... _miata.htm

As a test, I removed the MAF and revver her pretty hard - all fine. I set the cranking dwell to 4.0ms and running dwell to 2.2ms. After 3-4 minutes of idling the (stock) coilpacks were warm (but not hot) to the touch. The engine was alreay warmed up so the coilpacks were expected to be warm.

Jim