First off, this thread is for a 96-98 GT and not Terminator Cobra. This sub-forum has a lot more activity so I was asked to create my build thread here.
I had an issue with my car, most likely due to weak ignition. I spoked to Ed and we agreed that it would be best to upgrate to a MS3 ECU and IGN-4 coil packs to replace the OEM stuff. Of course, the MS3 opens up a world of possibilities and I want all the bells and whistles, one step at the time.
Here it is
The first thing I did after plugging it in, is upgrade the firmware to 1.5.2. I don't know why it shipped with 1.5.1 since the newer version is older than the release date of the ECU, but it was straightforward. I noticed the radiator fan would come up as soon as I turn the key on. It was not like that with the OEM ECU. It did a lot for debugging, the guys at DIYAutoTune were REALLY
helpful and they replied pretty much instantly. Turns out I had a dead transistor and had to ship the ECU back for repair. They repaired it the next day they received it, but the whole round-trip took 3 weeks because I'm from Canada.
Meanwhile, I had the time to install my Spartan 3 wideband controller from 14point7. Allan (the owner of 14point7) was also helpful and answered all my questions. I got two wideband and two controllers, so one for each side. They are wired to the MS3 via CAN BUS. The instructions on how to set up all this were very good. In fact, everything worked on the first try! I emailed Allan to congrats him on the product and instructions and somehow turned a bad day for him into a good day. It's nice to sometime contact the people behind a company to tell them when we are happy, not only when things go bad. I also set up the controller to start heating the sensors when the engine has been running for about a minute. This is supposed to improve the life of the sensor because they won't be hit with cold condensation while they are hot.
Here is the controllers, next to the J&S Vampire. All this is under the passenger seat
Next was tuning the idle. I managed to solve an issue I had with the OEM ECU since I converted the car to an automatic transmission (2016). When it's cold, and I get it in gear, it would stall. I searched for years to open up some more of the IAC when in gear with the OEM computer but it wasn't possible. Turns out the solution was so much easier. I had 14* timing at idle. I bumped it to 18* and voila, no more stalling when cold.
Another thing that helped to stabilize the idle a lot is getting the injector dead time correct. I had not touched this configuration from the base tune by DIYAutoTune and was trying to let VE Analyzer build a VE table and the numbers were all over the place and constantly changing. The car would also backfire, shake, ran terribly. All that was solved by having the correct injector dead time.
Next up was finally getting to the ignition. Once again, I listened to Ed's recommendation and got MSD 8.5mm wire for the Ford/Hemi pro stock.
I decided for fun to test the wires with an oscilloscope and compare them to the OEM wires. I was quite surprised at what I saw, and have no explanation for it. If someone can enlighten us I would be glad.
MSD wire is the yellow line, OEM wire is the blue line. I simply sent a 5V square wave using an Arduino and measured at the other end of the wire. The patterns are completely different and I would love to know why, and I know one is more desirable than the other.
Fitting-wise, I had issues with cylinders #2 and #3. There was no way the tubes would clear the Kenne Bell inlet, even cut at the shortest. I ended up removing the boots from the OEM-like wires, and used them on the MSD wire.
I went ahead and measured everything, made the wires, and checked the resistance (under 50 ohms per foot all the time), but after I had 6 wires all said and done, the seventh one had resistance in the kilo-ohms, sometimes even mega-ohms. It took me a couple of minutes to figure what was wrong. Turned out the wire wasn't crimped at the assembled spark plug side from MSD!
This is what it should look like
I assumed this was a fluke and proceeded to the next one. Same thing! I lost confidence, and good thing I did, all 8 of them weren't crimped! It's quite a job to remove the insulator and put it back in place, especially when the wires are fully assembled and the tube has
to come from the side where it's not crimped before installation, except now it's crimped. There was a lot of grease used to be able to slip everything back into place which doubled the time required to do the job that was almost finished. I don't know if they are designed like that (I hope not), or if someone didn't do his job on my particular set. Learn from my mistake and check yours!
Here's the bracket I made to bolt the driver-side coil-pack since OEM is 4 bolt and those are 3 bolts, and not at the same location.
I already had a custom-made bracket for the passenger side coil pack, I simply had to drill 2 more holes (and reused one)
I have two pressure sensors ordered (one for fuel pressure and the other for oil pressure). I will keep this updated as I work on this project. My plan is to use the option connector on the MS3 to wire those sensors.
MegaSquirtPNP Plug-N-Play Standalone Engine Management Systems by DIYAutoTune.com
Pin A will be ground, pin B will supply 5V to both sensors, C will be signal from the fuel sensor and H will be oil pressure.
That's it for now, I appreciate feedback, suggestions, comments, questions, etc