Closed loop control of propane

[65CrewCabPW]

Is there any known means of using an MS to use the duty cycle air/fuel mixture mechanism for controlling a propane carb?

Basically, it uses an O2 sensor, and a solenoid to alter the pressure inside the converter, to affect the air/fuel ratio in the mixer. Although I have read everything I an think of keywords to search, over the last few weeks, I have yet to find anyone address this. It works a lot like a gasoline carburetor mixture control, where the carb is set to marginally off of stoichiometric, and once the O2 sensor is warm, it uses a vacuum signal and a duty cycle solenoid to tweak the observed pressure inside the converter to achieve a regulated ratio.

I want to use the MS to control the ignition, and a kit to control the air fuel ratio is MORE than an MS. I would probably be using an MS1, or could use an MS2, if that makes it easier.

Any ideas?

[Matt Cramer]

It would probably take a couple of code changes as I believe propane mixers run on a fixed frequency, while fuel injector frequency is proportional to RPM. Other than that, I don't see why not.

[65CrewCabPW]

It would probably take a couple of code changes as I believe propane mixers run on a fixed frequency, while fuel injector frequency is proportional to RPM. Other than that, I don't see why not.

Long ago, I did take a couple of C and Java basic programing classes, but I am not qualified to re write the code, and certainly don't think I can hack it enouch to accomplish something like this, especially since I don't even know what it's written in. So, other than the theoretical and relatively obvious idea that recoding can make that happen, is there actually any way that I can have this work for me? Is there someone out there who will do it? Is it a matter of adding a new function to the system, and it gets included the next time the code's released, or ???

I don't know anyone in, nor am I familiar with the MS code writing comunity, so please forgive my questions, if they seem dumb. This isn't for me a wish list, it's the reality of a vehicle parked in my driveway that I need to have functional in 45 days or so. If that's not a workable time frame, or if it's just up to me to do, I guess I just need to know so I can move on.

I have been aware of the MS for quite some time, and this is my first chance to try to put it into use. I was going to go the route of normal EFI, but certain realities just kind of reared their head, such as adapters not being available anymore for a less popular engine ( slant six).

Thanks.

[65CrewCabPW]

I spent some time looking over the code and realized how complex the code is for running the injectors.

Could something like the logic for PWM idle (IAC) code be used, like a 20 hz frequency PWM signal that varies from 0 to 100, using threshelds the user chooses and a use defined center, for the EGO sensor voltage? The system already inputs the EGO voltage and it's global variable, right? The logic would something like a loop that checks the EGO value and adjusts a 20 hz, say 4 times per second, using user inputted values for 100 percent and 0 percent and a center (target) value from the EGO sensor, possibly extrapolating an approximate percentage of PWM as the average between target and min /max.

Just an idea. Perhaps it's easier to use the fuel code and merely change to a fixed (10 or 20 hz) frequency and input appropriate points like above? I'm just speculating here. I'm not enough of a programmer to do this on my own, as perusing the code didn't educate me much...

I'm intending to use MS1 and run a Ford EDIS ignition system, needing only timing input. So the MS control spark timing via the 2 wires to the EDIS system and drives an external PWM amp if needed to operate an air solenoid. I can work out the plumbing, including bleeds, etc.