As many of you know, I have had some spark advance problems lately. I have been doing some research and happened to look at the Megasquirt page. In addition to their basic controller, they are now offering a daughter card that will allow for spark advance control. Has anyone had any experience with the Megasquirt II and the I-tec components. Some of the sensors would have to change, but I think it looks very possible to run the Isuzu system with the Megasquirt controller. This may seem like a lot of work, but the more I get into my wiring harness, the more I think it is beyond repair. I would have to build a new injection harness, but I honestly think it would be easier to do than fixing the Isuzu system. Plus the Megasquirt system is more simple. I am also looking into putting the basic megaquirt on my '87 Trooper, using a GM 4-cyl throttle body. Anybody have any thoughts or experience with the megaquirt system? I would put this in the general section, but I think this discussion will definitely lean more towards the technical side, but placement is really up to the moderators.

Talk to houlster, I think he would know all about that stuff.

You don't need megasquirt II to do fuel and spark, you can easily do it with a standard megasquirt with the megasquirt and spark code. check out the forums and the info page, it will tell you all about it. msefi.com and megasquirt.info It's pretty simple to wire up, and there is lots of great documentation on how to do it. Houlster has done it on his amigo. You can do it on the itec just by adding an air temp sensor, and the tps from an automatic 2.6... the manual tps is just a switch... you need a resistive position sensor. The automatic tps has both. I'm working on mine at the moment, but I have a smog check coming up in a month, so I'm not going to put on until after that.

Rody

I thought the original megasquirt was fuel only. Don't you need the daughter card add-on to control the advance? I will check out the megasquirt forum and see what they have to say.

rody, post up some results/pics when you're done if possible... i have a feeling when the weather gets warmer, something like that will be great to have on my trooper to adjust for the high compression.

Rufus, Have you looked at the Megasquirt page? There is some great info. It really looks like it would be an easy retrofit to nearly any carbureted rig or existing EFI system. Are there any Isuzus, besides the 2.8 with TBI? I was wondering if maybe there is a throttle body that will easily fit on the 2.3 manifold. I can easily make an adapter, and will gladly share the plans for the adapter. I figure the throttle body from a GM car would work. I know the cavaliers and a few other 4-cyl cars had a throttle body. Is there an S-10 4-popper that would have a closer displacement? Most of the cars are 2 liter. The injector could be changed, but it seems like it would be easier to find one close first. I am just starting this investigation, but this seems like a tremendous way to pep up a pre-88 Trooper. I am interested in anyone's thoughts and experiences. Specifically what sensors were used and what tweaks were required on the Megasquirt code. I have purposely avoided a few vehicles just because they are carbureted, now it looks like anything can have EFI for a good price, probably less than the cost of a new carb for most rigs.

I ran MS for about a year with the turbo 2.6 before I pulled the engine. As for MS-II, I'm sure nobody has as it's not available yet unless you're one of the few beta testers.

I ran MS as fuel-only, although I do have a 4 cyl EDIS module I had planned on hooking up.

For spark, there is MegaSpark, MegaEDIS, and Mega Squirt-N-Edis/Spark which combines the fuel and spark code into the same hardware.

MS-II is a step further. Faster processor, more memory, bigger maps, will do fuel, EDIS, DIS, dizzy, etc. It incorporates a lot of the code people have written to do ignition. I am planning on this to run the 3800SC motor fuel and ignition.

To hook MS to the 2.6, I added in another water temp sensor and an air temp sensor. If you're going to do ignition as well, then you can use the existing water temp sensor but should check it's temp/resistance curve to make sure it's the same that MS uses standard. (Mine was, and you can use any sensor with code changes).

You don't really need to do any harness changes. I pulled the pins for the injectors from the big, multi-pin harness connectors on the passenger side fender. The rest of the stock harness I left alone.

Building a harness for MS is pretty easy nowdays. There are folks selling harness kits that give you all the color-coded wires and connectors you need for a pretty good price. Making an MS harness is pretty easy.

The one thing you need to do for ignition on the 2.6 is figure out how to get the signal needed from the distributor. It's not quite the same as the HEI GM distributor that's pretty much mapped out. I don't think it'll be that big of a deal though once you dive into it, figure out what the ignition code needs, and how you can get it from the 2.6 distributor.

--Dan

It makes sense to use the harness that is already in place. I am in the process of getting another harness right now.
Would you recommend keeping the port injection, or would it be more simple to go TBI? My existing injectors are already in pretty sad shape, so I would probably have to replace them anyway. I was leaning towards doing a throttle body on the '87 first, learing a little more about the MS system, and then tackling the '88, probably would transplant the 2.6 into the '87 since my '88 is a pile of rust, and the '87 is fairly rust free. Would you recommend that, or should I just go whole hog on the 2.6 from the get go? I am not too good with electronics, so I figured going simple first would be a good learning tool for me. On the MPI, is it possible to use the dizzy for position only, and then run multiple coils for the spark? How many coils can the MS controller handle? I think I read only one, but I am not familiar with the add-ons you mentioned, and perhaps they allow for control of more coils. I will have to do some more reading on the MS boards to learn a little more.
I think you are right about the 2.6 distributor. From what I can tell, two wires are for power, and one is position signal, and the other is the injector signal. I am not familiar with the newer GM distributors, are they also an encoder type set-up? Maybe a 2.3 dizzy could be used in the 2.6? Maybe a spring or weight change may be needed to get the advance curve right? I am just thinking out loud here, so please bear with me.
Thanks
Kris