Page 1 of 1

Identifying my hardware

Posted: Fri Jun 05, 2015 4:24 pm
by mlmccauley
Well, this is embarrassing.

I have a MS system which I built and installed on a 350 Chevy V8 in my 1960 Apache 10 pickup in '09. Having tuned the unit, I literally have not touched the injection system since then.

Not long ago, the TBI unit went south and had to be fully rebuilt. Having done this, I found that I had restored fuel flow out of both injectors, but the delivery rate had been substantially altered. The engine is running so rich that it will barely idle.

Given this, I'm obviously going to have to fully re-tune the unit. Problem is, I'm not exactly sure what I've got. I think it's a MS2, but I need to verify that before I go any further.

Following is info on what I have:

connector for engine harness - DB37 (on one enclosure end bell)
connector for (RS-232 serial) tuning - DB9 (on the other enclosure end bell)
3 LEDs are present next to the DB9
BOM and board drawings indicate that it is a rev 2.2 board
BOM indicates that the processor is a 68HC908GP32
triggered off ignition module tach output, no wheel.

I think the "DB9 and 3 LEDs" indicates that it is MS2, but I noted that a rev 2.2 board could be used in an MS1 as well, so I'm not sure.

If I need to obtain any info off the unit that would conclusively pin down what it is, please advise and I'll do so.

Lastly, given the age of what I have, what updates (firmware, other) would I be wise to install prior to tuning?

Thanks in advance for the help!

Mike

Re: Identifying my hardware

Posted: Tue Jun 09, 2015 6:53 am
by Matt Cramer
The 68HC908GP32 means you have an MS1, so this would be an MS1 V2.2.

Re: Identifying my hardware

Posted: Tue Jun 09, 2015 8:35 am
by mlmccauley
Thanks for the info!

Mike