Megasquirt Piggyback

[Azrael]

I ordered the megasquirt 2 with v3.0 mainboard kit. I got paranoid about my soldering skills so I also got a stim kit.

The upcoming GPIO add-on looks interesting as it adds transmission control. The testmule for this project is actually a 4L60-E so support for the 4T60-E will essentially be right there.

[Barry]

Any updates?

[Azrael]

It's built and appears to work properly on the stimulator and Megatune. I'm waiting on some electrical connectors so I can make the install in the harness reversable. That way if something in MS burns out I'm not completely stuck somewhere. I'm THAT paranoid. Although my biggest fears are in the ignition tuning as that's what makes or breaks an engine.

[IsaacHayes]

Yeah if/when I do it I will grab the pigtails from a junkyard car for the harnes and ECM, so you can just plug between the two without modifying the car. So just unplug the ecm from the car, plug the custom connector between them and MS runs in piggy back mode. I would do this so if I didnt get it going/tuned I wouldn't be without a car.

[Azrael]

Started wiring it into the car. Just 2 grounds, sensor ground, power and TPS are connected. It doesn't look pretty but everything works a-ok so far. Soldering all the connections to prevent future issues.

[IsaacHayes]

OK the editing posts feature is jacked up, only will let me edit above the previous text....

I was going to add, you could use an additional CTS, so since you cant share it and the stock ECM/trans needs a CTS to function (wont lock TC if it reads too cold). Need to keep the stock MAP as well for trans, etc.

Are you going to let the ECM control as much as possible? (trans, idle)?

[Azrael]

Yea the stock PCM is running everything except fuel and ignition. So it's still controlling the transmission, EGR (if that'll even work properly with MS, might have to disable it somehow), evap, cooling fan, fuel pump turn-on, speedo signal to the gauges, a/c system and the IAC.

I'll be using a dual-output CTS (ACD#213-815) in the LIM. There's another CTS in the rear head for the temp gauge but I'll have to find a work-around for that when I finally do a cyl. head/engine swap as the newer gen 3 heads don't have the threaded hole for it. I have to use a 2nd IAT sensor too but that's a simple matter.

[IsaacHayes]

I hear there is a spot in the back of the block, unscrew a coolant plug and it will screw right in.

[malachi]

Subscribing to this thread for sure.

I currently run a Quad 4 on MS in my Storm and plan for a 3.0 GM 54* motor swap and somehow make a 3100 ignition system work on it.
so learning all the info on these motors and the successfull MS conversions.

[XLR8ING]

Figured I'd post a couple of pics of my own MS2. Unfortunately it's not in the car yet, but I assembled it myself and ran tests. Seems ok so far. I'm curious as to how your set up works. I'll be running similar config myself, but i'm not sure how much, if any, the stock ecm will do.
And of course running the Innovate LC1 as well.

[Barry]

Figured I'd post a couple of pics of my own MS2. Unfortunately it's not in the car yet, but I assembled it myself and ran tests. Seems ok so far. I'm curious as to how your set up works. I'll be running similar config myself, but i'm not sure how much, if any, the stock ecm will do.
And of course running the Innovate LC1 as well.

How bad was the assembly? And did you have any prior circuit building expereince?

[malachi]

They are pretty easy to assemble. I had virtually no prior experience and just followed the directions. It is pretty straight forward. The big key is to build the stim board first. It is much easier, and will allow you to test various parts of the build as you go along.

I had some help building mine from a guy who does them but I'm pretty sure I could have done it without help.

[XLR8ING]

Hey there,
It's relatively easy, but I've built and designed circuit boards before in high school and college. I didn't get the stim board, so I have no experience with that.

Like the manual says, if you have no experience, practise on some cheap starter kit first.

Good luck!

[pocket-rocket]

Radio Shack sells these 2x2 boards that are set up for soldering chips and jumper wires too. IIRC they are not expensive. Couple that with some cheap resistors, and you have a perfect cheap soldering practice outfit for probably under $10. Soldering is easy, just don't overheat your stuff, and don't rush it. Make sure you get it hot enough, and don't move the components after you remove the heat. If you get a dull or hazy joint, reheat it till the solder flows again, then remove the heat. Cold joints will give you fits, so make sure all of your connections look shiny after they cool. Oh, and don't make solder globs, only use as much solder as you need, excess can lead to bridged traces (shorts between portions of your circuit that shouldn't be connected).

These are pics of the board I did 13 years ago in electronics in a regional competition. The bridges are fine, the pads were connected together before I soldered it :P







The pics don't do the thing justice, I scored extremely high on this board :P

[Barry]

I took a digital electronics course last year, and taking advanced analog electronics this year. I should be fine with the soldering, however, ill get a better iron.


Any updates on your setup? Once I get mine running its MS time.