1999 Saturn SC2 Ignition Install

S.Bretz · Post by **S.Bretz** » Thu May 25, 2006 3:12 pm

Setting the dwell to 25ms caused me nothing but problems. I am having good luck with it at .5-1.0 ms. ANythin over that and I get surging up top.

I have also noticed that the stock ICM pulls timing between 6750 and 7200. I guess it was built into the ICM so that the timeing would be pulled as the fuel cut kicked in.

Set the max spark duration from 1.5 to 2.0 ms, the shorter the duration, the hotter the sprak flame. 1.5 seem so be a good number.

I'm gonna try another ICM off another car and see if that helps out any, but as of right now, the 95 sucks between that spot mentioned earlier.

bluetrepidation · Post by **bluetrepidation** » Thu May 25, 2006 7:01 pm

6750 and 7200 huh? Well that stinks. I've been running 25ms dwell for some times and I'm not having any surging issues. But I don't have a turbo either. I guess you got your engine rebuilt? Spark duration? Doesn't the ICM handle that? Or does this setting still have some kind of effect?

A.J.

S.Bretz wrote:Setting the dwell to 25ms caused me nothing but problems. I am having good luck with it at .5-1.0 ms. ANythin over that and I get surging up top.

I have also noticed that the stock ICM pulls timing between 6750 and 7200. I guess it was built into the ICM so that the timeing would be pulled as the fuel cut kicked in.

Set the max spark duration from 1.5 to 2.0 ms, the shorter the duration, the hotter the sprak flame. 1.5 seem so be a good number.

I'm gonna try another ICM off another car and see if that helps out any, but as of right now, the 95 sucks between that spot mentioned earlier.

S.Bretz · Post by **S.Bretz** » Thu May 25, 2006 7:22 pm

Reporting back:

After the last post, I finally got around to messing with it. I was messing with the dwell a bid to see if the ICM would do its own dwell and not need the MS signal...well it DOES need a siganl...so I had turn the dwell up from .5 to 1, then installed another ICM from a 94. As soon as I cranked it up, it misfired like crazy. It stalled a few times, and then while it was running I turned the dwell up to 2.5ms....BIG improvemet. I left and noticed at low rpm and full throttle, it was still missing. SO I bumped it up to 25ms and it rean great the rest of the way home.

Only problem is that I still have a problem with 67ishh hundred to 7200.

I'm gonna pull a data log and makes sure its good on fuel and stuff. I noticed with the current ICM, it idled leaner, and leaned out easierwhile cruising, so I figure I might need to mess with the fuel tables a bit and take/add a little timing here and there.

tebriel · Post by **tebriel** » Thu May 25, 2006 7:24 pm

hey sam could you send me or upload your msq file? I tried getting the ms2 to run on the turbo car a couple days ago but it ran so lean it didn't even register on the wideband. we tried richening it up, but it didn't make a difference. I must've missed a setting somewhere but i'm not sure what.
-teb

S.Bretz · Post by **S.Bretz** » Thu May 25, 2006 7:30 pm

Yeah, give me a few minutes. I have to go out to the car and grab the laptop...an then let it load. I'll get the most resent. It is with the 96lb/hr injectors and the new intake manifold and the bullforg cams, so I don't know how it will work for you...especially at idle. I had to made a pretty aggressive timing advance wall to keep it from idleing...and I Have bee idleing it at about 1300-1400. Under that the injectors can't spray and less fuel and the it chokes out....i'llbe back.

S.Bretz · Post by **S.Bretz** » Thu May 25, 2006 7:46 pm

ok...here is a .ini file witch I modded to accept up to 25.5 ms of dwell...copy it over the .ini that you named "megasquirt-II.ini" or something like that. Its in the "mtCfg" folder.

Next is the .msg file.

Keep in mind I don't use the IAC, so you will have to mess with those numbers if you want that.

tebriel · Post by **tebriel** » Fri May 26, 2006 4:36 am

ok awesome! yeah i'm not using IAC, and my injectors are 86#'s so it's not too far off. I'll compare maps and see if i'm way off or something. My map works great for the MS1, but when i port it over tot he MS2 it doesn't seem to work.
I'll try this out, thanks.
-teb

bluetrepidation · Post by **bluetrepidation** » Fri May 26, 2006 5:51 am

Seems like something was up with that other ICM. BTW does anyone have a stock Saturn ignition timing map that I can look at?

Keep us posted,
A.J.

S.Bretz · Post by **S.Bretz** » Fri May 26, 2006 10:57 am

There might be one over on TSN. I remember seeingone about a year or 1.5years ago...but I don't know where its at. YOu would need to search and start wading in the deep end.

bluetrepidation · Post by **bluetrepidation** » Fri May 26, 2006 3:23 pm

Yeah I found a MAP that was in hexadecimal on there once and the status was "we're still trying to decipher this."

A.J.