I installed some new connectors for my CAS that I got from the Madza dealership, they were salvaged from a junk wiring harness, so don't ask me a part number. Anyway, I had the polarity reversed on the CAS that senses once per revolution.
After changing it, I was able to get up to 7100+ RPM without any stumbling, and I didn't go any further because the brakes wouldn't hold on pavement. (That is with a 68 dia x ?? prop, just for ground test purposes) For future reference, on the sensors, the side of the sensors that are to the left, when you are looking at the front of the engine are the side that have the lead that is common to both sensors. My engine didn't have one of the CAS connectors, so I used the small female slot connectors and RTV. Well, you have a 50 percent chance of getting it wrong that way, and of course I did.
Brian Trubee