Well, after much confusion on my part, it's finally sorted out and the car is running and idling okay.
Here's a couple pics of my FB install:

http://home.mindspring.com/~wilkinsjr/enginebay1.JPG
http://home.mindspring.com/~wilkinsjr/enginebay2.JPG

I got a writeup going for the 12a. There are really only a couple of things you need to do that are 12a specific, so far as settings/install goes. But I am going to try and cover stuff from a fresh install, how exactly you need to install the CAS on these engines, and some common pitfalls that aren't covered in a central place. I hope to have something done this weekend.

This is sweet!!!

 

NICE! good to hear that you got it running. I think that makes 4 people running full ignition that I know about.

What version of the firmware are you using? I'm going to post my own version of 026i with my staged injection changes tonight when I get home from work. I originally made my changes to 027d, but that has a bug where ignition goes nuts at 4000 rpms, so I backported it.

I also read that post of yours on msefi.com... About trailing. Trailing only fires above 800 rpms on the megasquirt. There are technical reasons for this that I can explain if necessary, but trailing not firing during cranking is totally normal. If you drop below 700 rpms once trailing is on, it'll also drop the tach on the dash to 0... it's kinda funny actually.

I think I'll post a note in the FAQ about this because I've had to repeat this several times... people start freaking out that ignition isn't working because their tach isn't bouncing, but really leading is working fine, and trailing just isn't coming on (as designed).

 

jayroc,

Congrats! It's great to see another successful installation. Looks like you've got a very similar system to Mike Roberts, who's had excellent results. Will you get some tuning time in during the holidays?

 

I have plans to modify a 13b manifold to fit this 12a, and drill/tap it for a EGT probe. Then I'll fit a fuel pressure sender where my current gauge is on the rail. Once I get these logging to MS, I want to take it to the dyno. That probably won't happen until sometime in January, though.
Mike helped me a lot during the initial install. Very nice guy. I believe he was one of the very first people to put MS on a rotary, and quite possibly the first for a 12a.

Well, the problems I ran into were 95% CAS placement. Apparently, I got confused as to the spark terms used on the MS. I set my timing at 5 degrees BTDC instead of -5, and that is how I placed the CAS, hence the backfiring.. Totally my misunderstanding.. The only thing worse than not knowing what you're doing is believing you know what you're doing and it's the wrong thing!
The tach wasn't working, and that set off my concerns, but I also didn't know what my setup SHOULD be doing, as the lm1815 and the behavior on the stim was all new to me.. The big thing that lead me to think I wasn't getting spark (aside from it not starting and tach not working) was after I put the timing light on while somebody cranked it, there was no spark on either leading side, then after moving the tach lead to leading, it still didn't act like it wanted to move much. I thought the backfires were some kind of intermittent spark problem..

I did see a trailing 800 RPM behavior post of yours, muythai, after my last post at msefi.. That lead me to relook at the CAS install. but I thought the stock FC did fire trailing at cranking? I remember the tach jumping on my FC I used to have a few years back..

Anyways.. Those were some issues that I ran into. Like I said, I'm doing a writeup for the 12a. I'll post it up on a webpage sometime this weekend.
Correct me if I'm wrong, but there should be two ways to install the CAS correctly.. The first is to stab it at TDC and reset the trigger angle, and the second would be to stab it at -5 BTDC. Does that sound right?

 

BTW, thanks for letting me know about the firmware problem, muythai. I'll reflash whenever you post 26i. I am running 27e, right now. I wanted to stay away from 28. Too scary for me.. heh

 

Update: I believe the best way to install this CAS on a 12a is to line up the pulley with TDC, find the mark on the CAS and set the trigger angle to 55. If you don't reset the trigger angle, you won't have enough room to adjust it correctly when you zero the timing. I'll take a look at it again some other time, though, because I was getting some funky readings using two different methods.. This method works best, I've found, however. I may even drop it down to 50 degrees to allow for some more adjustment room.
Also, I guess my engine or starter is old because I had to change the cranking RPM to 200 before it would start up easily.

 

yeah the FC does fire trailing stock, but the MS doesn't due to the fact that there's too much time between ignition events at those low revs... meaning a 16-bit number isn't enough to store that amount of time until around 500-600 rpms... jsmcortina made the cut-on point 800 rpms to give us a buffer and make sure that trailing is reliable....

I guess it'd be possible to write code to do trailing at lower revs, but I don't think it's really a big enough deal to make it worthwhile.

 

You could bridgeport the engine and you will never see 800 RPM. :-)

 

Where did you post it? What is added to the staged injection?

....Off-topic...
Can MS do sequential injection? Just wondering! I noticed there are four different injector wires.
........

I just ordered my v3 board kit and stim kit(Christmas Present)! YAY!

Sorry for stealing your thread

 

The MS can't do sequential, that's something that will come when the router board is done.

I didn't post it yet, I'm going to post it in a few minutes.

It adds 2 features, 1) insted of staging coming on instantly, it allows you to specify a number of ignition events to stage in over... and then gradually stages in over that number. If the number you specify is too high, it'll just stage in over however many events it takes for the pulsewidth to get to the correct staged value. 2) I added a coolant temp parameter and a delay time for idle advance. On some rotaries, the engine likes to idle at 5 deg ATDC, which gives you an extremely smooth idle. However, if you allow the engine to go to that advance immediately when you let off the gas and the revs drop, it could stall.... so the delay (in seconds) tells the MS to wait for a few seconds before going to idle advance after all the conditions for idle advance are met so that the engine can recover from the rev drop first. The reason for not putting the 5atdc in the ignition map is because the extrapolation between -5 and the next value in the map can cause a nasty oscillation while you're driving.

Ken

 

Hey, muythai, did you include 26h or 26i in the download? I just flashed my ECU and it said 26h.

 

get that write up posted up ASAP. I have been interested in squirting my 12a so any info (detailed as much as possible) would be great. I am a bit confused as to how you would set the trigger angle to 55? I haven't used a CAS or removed one (I have set timing with one and wired one up, but never had one removed to know about how to set it to 55). Thanks. Keep up the good work everyone.
Happy Holidays

 

It should say "026i_mod"

Let me check to make sure I got everything correct in the version I posted as far as the versions go.

EDIT: You should be downloading my modified version from the stickied "Firmware" thread for now, which is 026i_mod... 026i will work but it doesn't have my staged transition code... the 026h that it reports when you use the normal 026i just means the flash format on the megasquirt chip's flash has not changed since 026h.

Ken

 

What version of Megatune do you recommend for this?

[Edit: Guess I should read the readme.txt first - 2.25b 627]

Thanks and have a wonderful Christmas,

 

Since this answers your question, I'm sure Ken won't mind me posting this PM:

 

>_< I was downloading the code from the MSnS-E Download section.. Oops.

BTW, I am wanting to use the dual table switch function. How does the code handle that? Specifically, with the trailing split table.. I am just hoping there won't be any crazy problems when I switch.

Can I use a later version of MT? I thought I was stuck with 627 on this firmware..

The writeup is comin along. I may work on it late tonight and post it as "beta".

 

you can't switch the trailing, there is only one trailing table. The trailing will just use the same split from whatever's in the leading table that you're using at the time.

You're not stuck on beta 627, just install the right msns-extra.ini file in the right place and you're ready to go.

 

Sweet. I will check that out. I was missing my "idle advance" setup. That is pretty handy..

That's cool about the switching.. I don't know how the MS handles the switch and I wanted to make sure that trailing support was still active if I was using VE3/Spark3..