How much of this will work with MS3x ?

[B85]

I keep reading and found this. This is all new to me and was wondering how much of this will work with my MS3x ? Or is this just to old info ?
Thanks,Randy


"Buick 3800 C3I DIS and MSnS-E Setup Info
Postby WopOnTour » Fri Mar 18, 2005 11:58 am

I have been doing some extensive testing on the Buick 3800 Computer Controlled Coil Ignition (C3I) system for MSnS-E (Fidle as spark control) using my MS and a 2000 C3I mockup that I have. The scope waveforms and patterns look very promising.Here’s what I have learned so far (although keep in mind this was done in a mock-up state only and NOT on a running engine) If anyone out there that wants to MsSquirt a Buick 3800 and needs additional assistance or support (ie schematics -etc) please feel free to PM or email me

In order to potentially run the C3I ignition as used by the 3800 with MSnS-E you will need to REROUTE the following signals from the C3I module to the MS:

- connect the purple/white wire (C3I ignition module terminal D) to PIN24 of the DB37@Megasquirt. This C3I signal is commonly labeled “low resolution engine speed signal” is actually a digital 3X (ie transitioning every 120 degrees of crankshaft and) near identical to the old DIST REF but is “synthesized” by the C3I module from the 18X hall-effect input (18/6=3)
*NOTE-This circuit was previously routed to the oe ECM.

- connect the “IC Timing signal” (aka 5V Bypass) which is the Tan/Black wire at terminal B of the C3I ignition module to pin 27@DB37 of Megasquirt. James has now configured this to go to 5V when RPM>400 as discussed here: http://www.msefi.com/viewtopic.php?p=41 ... ght=#41529
*NOTE-This circuit was previously routed to the oe ECM.

- Finally the Electronic Spark Timing (IC timing control) a white wire at pin A of the C3I ignition module to the reconfigured LED17 @ Pin25 at the Megasquirt DB37 connector.
*NOTE-This circuit was previously routed to the oe ECM.

* These mods assume you have:
-D8 jumpered (shorted) or removed and bridged
-XG1 jumpered to XG2
-Fidle/LED17 and LED19 reconfigured as outputs as shown here:
http://megasquirt.sourceforge.net/extra/setup-hei7.html

What I did was trim a 1000 ohm resistor on one end and with a small needle nose, make a small J-hook on the lead to hook under the RH end of R23 and R27 (as viewed with the DB9 serial connector on left) and soldered them (vertically) there. You might as well do R26/LED18 while you are at it a.

Then I bent the other resistor lead into a "reverse-S" shape so as to connect to the cathode(-) side of the case LEDs ("top" LED leads as viewed with serial port on left) and soldered them there.

Then add 2 small "hookup" wires to connect to these outputs circuits to X11 and X12 (as well as the "extra" output #4 from LED18 to X13)

Then wire:
X11=DB37 pin 25 to your EST (timing control) circuit PIN A of your C3I module

X12=DB37 pin 27 BYPASS to PIN B of your C3I module

DB37 pin 24 of the MS to PIN D of the C3I module (IGN REF)

*You MAY want to make sure there is identical ground potential between the MS and the C3I module by connecting Pin L of the C3I module to the same engine ground point as your Megasquirt.

Here's a link to some pics showing the internal wiring mods in one of my Megasquirts
http://www.msefi.com/viewtopic.php?p=43 ... ght=#43557

MOST of the remaining connections at the C3I ignition module MUST REMAIN connected as factory. These include IGN+ (terminal P), Ground (terminal K) and the circuits to the various hall-effect sensors (terminals G,H,J,M and N) While all of these sensors are not necessary they do share a certain amount of circuitry (see schematic) and will facilitate future possible use of these signals (for possible enhancement through wheel decoding or maybe SFI on the MSII)

The following circuits at the C3I ignition module that can be safely removed as they went to the OE ECM. (actually it’s recommended that these circuits just be either “clipped” at the ignition module to maintain connector seal integrity or just insure they are properluy "dead-ended") So you can safely "clip the wires to IGN MODULE terminals
C (Medium Resolution Engine Speed Signal)
F (Camshaft Position Signal) and
L (low reference)
*The wire at E can also be clipped as AFAIK was never used anywhere.

This should work for any Buick 3800 from 1988 to present

NOTE: Depending on the C3I module used you MAY have to bypass the Opto coupler within the MS directly connecting the IGN REF input at pin 24 to the opto output as outlined by James' in the following thread: http://www.msefi.com/viewtopic.php?t=7034
*NOW ON TO GM-Direct Ignition Sytem - Stay Tuned

Regards
WopOnTour
Last edited by WopOnTour on Sat Oct 15, 2005 6:27 pm, edited 10 times in total.
WopOnTour
Helpful MS/Extra'er

Posts: 98
Joined: Fri Aug 06, 2004 12:53 pm
Location: Nowhere man "

[subwoofer]

Given that the post is ten years old and that Megasquirt was in its infancy at the time, do you expect any of it to still work the same?

[B85]

With my build using a 3800SC ,I 'm looking for all the help I can get. Just was hopping their was something their.
Randy

[charged3800z24]

You have the 3.57 board, correct? I'm not 100% sure on what applies for that board. I know it is still relevant for the 3.0 board that I use, as I've had that since MS1 through MS3. The wiring and hardware mods are what I use today on my C3I setup. I driven the car a couple years on that setup, so yeah, I'd say it still holds some worth.

[charged3800z24]

OK, looks like if you use the v3.57 and MS3X, then the difference is just the Spark A and Spark B references. Looks like you route these directly to the MS3X on 14 33... With the new setup, it looks like the board has jumper and a RES Pot to adjust. The Tuner Studio settings are the same as I gave you in the MSQ. Since I started Pre MS3X, I used the wiring per the old manual. This wiring is still the same if no MS3X is used. Or you can use it with MS3X as I have mine.

Then wire:
Was = X11=DB37 pin 25 to your EST (timing control) circuit PIN A of your C3I module
Is now = Spark A on pin 14 MS3X (EST)

Was = X12=DB37 pin 27 BYPASS to PIN B of your C3I module
Is now = Spark B on Pin 33 MS3X (ByPass)

Stays the same = DB37 pin 24 of the MS to PIN D of the C3I module (IGN REF)

[B85]

Thanks charged !

This is what I was hopping to find. With luck and people like you, I may just get this built and working.

It would sure help if their was a "Build" archive for this info. Ok, so I'm lazy . We could put a builds their (after it is found to work ) .

Randy

[charged3800z24]

No problem. Also I clarified something in my previous post, see above. Pins 14 and 33 are on the MS3X header not the MS3. Pin 24 for IGN Ref, is still MS3 Header. Make sense?

[B85]

Thanks !

But you know you are talking to the blind guy in the room ? LOL

"Have soldering gun will travel "