ECU P4120534 Super Stock / Pro Stock / Nascar

ecuII.jpg ECUApplication.jpg ecu III.png ecu chart 2.png Steve tons of differences. I have been testing them on the distributor machine in a mock up with a scope. Specs are pretty much as stated, obviously I dont have all the numbers and a matched ballast resistor value does make a huge difference in performance. Go with the rated one for the most performance.