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yarin
Hey Everyone,

I finally decided its time to flip up the spark switch on my Megasquirt installation. I'm running MS II V.3.0 with the high current ignition driver setup triggering the negative side of a bosch blue coil. RPM signal is coming from a Pertronix hall sensor with a 1.3K pullup resistor the negative side. No R57 on the main board. Dizzy is a "frozen" 009, i glued the advance mechanism.

I wired everything up and tried cranking it tonight. Several almost starts but its misfiring. I know my advance was approx 8 degrees at idle. I tried a variety of settings but just can't get it to fire correctly. I threw a timing light on the coil and it looks like i'm getting spark.

Can someone with a similar config please post their settings?

Thanks,

Yarin
yarin
I found someone else's settings on MSefi.com. Their trigger offset is much higher than i expected, 58 degrees. I understand this number should be my base advance according to my timing light, but first i need to get it started. I guess i'll try a much higher trigger offset and see what happens.
yarin
bump.. anyone?

i tried an offset of 58 degrees and still have the same issue. must be something simple i'm missing.
Aaron Cox
not familiar with MS ignition.. but im trying to get my head around this.

so dizzy is locked. NO advance. cool.

so it obviously needs the dizzy signal well before the piston gets to TDC...

is that what 'trigger offset' is? it sees the signal 58 degrees BTDC?

that seems like it should work... as it has some time to delay even at high rpms when you are running ~30 deg advance... sitll gives it lots of time to do its thing...


my question - what is the engine trying to do? is it spinning reaaaally fast? (too retarded) or is it kicking back (too advanced?)

big backfire? (90* off)

what is your actual 'trigger offset'? ie how many degrees btdc is it getting the signal.....?
bd1308
If you figure it out, lemme know. I'm only two steps behind you.
DNHunt
I wish i could help you but, I just let the EDIS module do all that stuff.

Dave
yarin
QUOTE(bd1308 @ Oct 10 2006, 05:41 PM) *

If you figure it out, lemme know. I'm only two steps behind you.


Well.. it works. and i'm impressed. Didn't drive the car yet, just got it to idle and matched the trigger offset with my timing light.

I had mine set to Rising Edge for input ignition capture instead of falling edge. That did the trick. Aside from that, you basically just have to get it in the ballpark then dial it in. my final trigger offset was -8.5deg.

The latest Beta of megatune 2.5 supports custom trigger wheels and knock retard. They are really coming along with this project!

The addition of spark was pretty easy:
1/2 hr to wire it all up. just two wires.
15mins to epoxy dizzy
1.5 hrs to set up the parameters and tune a little.

i'll spend some time on it this weekend and see how spark behaves under load. the car was running just fine on fuel only for a few months and then i decided its time for spark.

thanks guys mueba.gif
bd1308
I just have to build mine, run it, and then do whatever you did to get it to work.

I'm screwed sad.gif
yarin
QUOTE(bd1308 @ Oct 10 2006, 11:09 PM) *

I just have to build mine, run it, and then do whatever you did to get it to work.

I'm screwed sad.gif


Well if you have any questions defintely drop me a line. I have pics and plenty of experience fighting issues. But i'm up and running, thats all that counts.

Good luck.
DNHunt
Here's something I can help you with. Here is the timing curve I've been running. You'll problaby want to tweak it some but, this should get you started. You may not want the same aqdvance at idle and you may not rev as high. The numbers may need to change some but, the shape should be pretty good.

Dave
yarin
Thanks Dave!

Can you export the table and post the plain text file?

Thanks
yarin
DAve i typed it in. Took it out for a quick ride, so far so good.

Megasquirt Ignition with the direct coil driver is a success! drunk.gif

Pertronix Ignitor
Bosch Blue Coil
Frozen 009 Dizzy
MS II V.3.0
matt_o_70
I have been thinking of doing a project like this.. rather than putting the money into a mallory distributor. Would you do it again?

now that winter is here I am thinking hard about taking up the project.. where do I start looking for where things are with MS these days?
yarin
QUOTE(matt_o_70 @ Oct 13 2006, 10:56 PM) *

I have been thinking of doing a project like this.. rather than putting the money into a mallory distributor. Would you do it again?

now that winter is here I am thinking hard about taking up the project.. where do I start looking for where things are with MS these days?


I don't have the time anymore, but if i had to do it again it would take me 1/4 the time.

go to www.megasquirt.info for the main site. i bought all of my parts including an innovative wideband O2 sensor at www.diyautotune.com VERY happy with their service. the megasquirt forum is www.msefi.com check that out too.

click on the link in my profile for pics and info on my build. i still have to write something up one of these days.

hit me up with any questions.
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