Torslund wrote: ↑Thu Jun 24, 2021 12:09 pm
This is were the distributor is read. Is there something that can be changed so the pulse reading is divided?
Yes, but there are several options to see the tooth division you are after. One is to mod the code in one of multiple ways. Another is to configure your trigger signals in a way that is readable by current code.
As you are wanting to run your V12 as a 4-cylinder, then configure for a 4-cylinder. With a 12-tooth trigger wheel, you can do this various ways, and one of several options is to add a cycle signal ("cam signal") into the mix, retaining the 12 teeth and adding one more separate signal. There are literally dozens of ways to get a single signal once every 720°. One example is adding a 2nd sensor to the distributor with a single target tooth on the shaft. Here is a commercial example of that approach:
Jaguar V12 12•1 distributor.png (161.07 KiB) Viewed 4618 times
I did something similar by cutting a groove in the dist shaft, instead of a tooth, and adding a little ATS6x7 biased Hall sensor to read the shaft. You could add a disc with one tooth and punch a ZF (Cherry) GS sensor through the side to read it. Or a GS sensor in the valve cover or timing cover to read a rocker, cam lobe, timing gear, etc. Stuff like that.
Lots of creative options to explore. There are benefits to adding a cycle signal, such as to start injections on the same cylinder set on every startup, for more predictable fuel distribution. Of course the obvious option with the added signal would be to move to 6-cylinder fueling and quasi-sequential (double-shot) fueling on paired injectors, using re-purposed HC outputs (for example).
Another option is to run two Speeduino controllers, one for 6x fuel and the other for 6x waste-spark ignition. Tuning can be simultaneous in TunerStudio through CAN. The downside to so many options is picking which ones.
You can chase code changes, or you can chase solutions to use current code. You have requested a decoder change and code options here. If it were me, I'd chase configs to use current code while I'm waiting for responses. Your call!