Anonymous D

The SN95 donor car for my 5.0 Miata is an auto, so I cant use that one unless I get a chip or something for it.

I know I can get the computer I need for around $100, and its like $415 for the DIY kit for the Megasquirt. I know I'm going to need it eventually though because I plan on doing H/C/I down the road. So my way of thinking is to just get it now and not spend the $100 on the regular computer.

Plus Id like to use Shadow DashMS and a tablet for my dash board, and you have to have the Megasquirt for that. Plus it'll be really cool.

Apart from not having to buy the other computer only to replace it with the MS later, what would be the pros to having the MS on a mostly stock engine?

97miatam

I went ms2 for my build from the beginning. On a stock engine I don't know that you will be able to make much more power with it, but it is fun to tinker with change the fuel map for cruising and WOT

wcw5023

If you KNOW youre going to get it in the future. There is no better time than now. Shouldnt even be a question. Your wiring will turn out neat-er, and youll be able to start setting up your dash how you want it. I <3 Megasquirt

acedeuce802

The gains on a stock motor won't be a whole lot, but there are plenty of other reasons that Megasquirt is worth it. Every time you make a modification, you can optimize the tune for that engine configuration, rather than relying on the stock MAF sensor to remain in calibration. The ShadowDash is also a plus (I'm going to be running a Raspberry Pi and TunerStudio for my dash).

The features with Megasquirt are also a huge benefit. Especially with MS3, having several spare analog inputs, digital inputs (for 2-step, datalog, tableswitch, etc), flex fuel, traction control, and all the other features should make the driving experience pretty awesome. I'll be running MS3pro with a JBPerf expansion board on my LS1. Which Megasquirt are you planning on getting? After tuning/driving on MS2 and MS3 back to back, I would definitely recommend a minimum of MS3+MS3x.

I would go for it now, mostly for the reasons that wcw mentioned. If you're in the initial build phase, I would much rather "do it once, do it right". Make your wiring harness made for Megasquirt, rather than adapting/hacking later on. If you haven't used Megasquirt before, there is certainly a learning curve. It's not too difficult to pickup, but the more practice the better. So learning right from the get go will be beneficial.

cvx_20

I put MS2X on my bone stock 302 in anticipation of installing a better motor some time soon. I figured it would be easier to go thru the learning process on a mild motor, and there is a learning process. The beauty of MS is its tunability, the downside to MS is its tunability.

As it turned out, I recently acquired another conversion with a somewhat built 302 that ran very poorly on the stock A9L so I converted it to MS2X as well. The flexibility of MS is amazing. Tunerstudio is amazing. I highly recommend both, especially for a Ford which has limited options for tuning software. An LS motor, on the other hand, has some alternative software available that make the $100 stock ECU attractive.

Mike

MRM331

Are you sure that your SN95 computer can not be used on a Manual? I know for a fact that the earlier fox a9l's can and are actually desirable since they have a 500 rpm higher redline.

I used a MS2 designed for a SN95 Mustang on my last car and it was awesome. Jumping up to the MS3 is even better as it gets you true sequential injection (the best you can do with the MS2 is batch fire) and enough I/O's to run traction control, launch control, shift lights, LSx coil-on-plugs, multi-function exhaust, etc. For what you will pay to have a Fox or SN95 ecu properly tuned you can pick up the MS2 or 3 and tune it yourself.

If this is the way you want to go start reading up on it NOW and plan on a large learning curve. I began studying the theory behind every aspect of fuel injection about a year before I installed the MS2 adn even then it took another 6 months to have it running where I wanted it to.

Good luck,
-Jason

Anonymous D

The auto computer pulls timing when it thinks it needs to shift. So that would cause problems. I could get around it with a cheap chip. I had one from Moates when I had my SN95 and it worked great, but I had a buddy who had the tools to program them, so I paid $60 and got a chip programmed how I wanted. If I went that route, Id have to get all the equipment this time though. So it would raise the cost signifiantly, and Id still have to ditch it eventually.

I plan on either going with this,
https://www.diyautotune.com/product/...-no-connector/

Or this.

https://www.diyautotune.com/product/...-manual-trans/

I'm very familiar with a soldering iron, got a nice set of tools when it comes to that.

And thanks for all the input guys, Ive been doing a bunch of research, and I know its a steep learning curve, but I know I can figure it out. Any books or anything in particular I should check out?

Anonymous D

And after a bunch of scouring the web, it seems like the computer I need is in fact closer to $200, so the MS is looking better and better.

97miatam

Do it! I was worried by it because I had never built a circuit board or wired a car. Just following the instructions and taking my time yielded a car that fired right up first try. If I had a little more money I would probably buy an MS that is already built because it took me 10+ hours to get it assembled.

MRM331

This makes sense. When I convert a SN95 harness for use in a V8 Miata I pull about 1/4 of the harness' wires out because they just run to the trans plug. The auto trans harness has about 35 wires and the manual has 2.

-Jason

MRM331

I agree. If you are up for the challenge of tuning the car go for it. If you do this I highly recommend paying the extra money for the TunerStudio upgrade/license as it opens up "AutoTune". Autotune lets the MS tune itself as it drives by smoothing out its Volumetric Efficiency table on its own. I found its a great tool as you can make a change else ware in the tune and Autotune will fine-tune its integration into the tune with the VE table.

I made the decision to get mine assembled from them. At the time the difference was around $150. I felt that while I'm sure I could assemble it myself the time involved and the assurance that it is done correctly was worth the extra cost (sort of why people have me do their harnesses I guess). It looks like the difference now is more like $350 between the two you linked to. I would have built it myself for that type of savings.

If you go this route you may be able to save yourself some money by starting with a 86-87 speed density donor harness. The MS system is SD and uses only half the wires in a Fox harness (an SN95 may have more utilization due to the CCRM relay pack). Before I decided to build myself a stand alone MS harness I was planning on pulling out my converted 1991 Mustang harness and building a MS harness using a cheaper (and better quality) early SD harness.

The biggest resource I found useful when trying to learn was the MegaManual on line and the ECU sections of the Mustang Corral and other Ford forums.

Good luck with this all,
-Jason

acedeuce802

If you're handy with a soldering iron, why not just step up to an MS3+MS3x? You'll see significant driveability improvements over the MS2, and will have a lot more I/O's.

https://www.diyautotune.com/product/...th-black-case/

https://www.diyautotune.com/product/...xpansion-card/

Anonymous D

Good to know. Thanks. Still deciding if I want to do the harness myself or send it to you. How much will I need to deviate from martins manual if I'm going with the MS? I know Ill need to change it some since its an SN95 harness.

The harness is the main thing Ive got questions about at this point. Ill be able to use the SN95 harness correct? I dont want to have to make a new harness and TBH, that may be a deal breaker. Unless I could just swap the wires to a different plug for the computer.

Didn't see that. Thanks. Will those plug into the factory harness? That's a big deal for me unless its something as easy as swapping the wires to a different plug.

acedeuce802

You can use this and make a breakout harness: https://www.diyautotune.com/product/...104-pin-eec-v/

Anonymous D

Mines a 60-pin, but I see they make one for that as well. The $80 for that seems like its worth it as it would save me a lot of headache. Thanks

MRM331

$80 + $15 or so for a EEC-IV ECU from anything other than a 5.0 Mustang.

-Jason

Anonymous D

The connector itself? Ive got the auto computer. Why cant I pull that connector off? Or am I just misunderstanding you?

MRM331

You could use the connector from that ECU or sell it for $100 to $150 and pick up a cheap Taurus or Escort one for $15 to pull the connector from. ECUs from 5.0 applications seem to get a pretty penny, I could be wrong about your automatic SN95 one though.

-Jason

Anonymous D

The ones for an auto seem to go for around $100. If I can get one cheaper and sell this one, that is a good idea. No idea that the others were so much cheaper.
Thanks

Anonymous D

Yea there are Escort and Taurus ECUs for around $20 on eBay. Definitely gonna do that. Thanks for the heads up. I was gonna tear the 5.0 ECU apart. Lol