so i've given up on rebuilding the stock harness and using the stock ECU, mostly due to the lack of a harness and ecu lol. rather then spend money on it and risk screwing it up, also to remove the Iafc and pull a little more power from the engine? im wondering what engine management is everyone using? i have a subaru ej22 NA dual port exhaust, so a 90-94 engine. whats the most cost efficient stand alone system to use? computer and harness. i know its cheapest to rebuild the stock harness, but whats the most cost efficient stand alone system?

If you are keeping NA then i would look at the Haltech sprint 500. maybe not as cheap as some but who cares when it is heaps better to use.
Should be able to get a harness to suit the engine too.
cheers
Edwin

"outfront" ems stinger

Link

Megasquirt

peter (malaga_red75) told me about the ems stinger from outfront, but that ran him 1.5k. haltech sprint 500 looks like it will run 1k for just the ecu. any experience with megasquirt? and its costs/harness

You can get a Megasquirt II kit and harness for about $320 total. This will run your car fine with the stock Subaru trigger wheel VR sensors. The kit I built for my Subaru EG33 took about 6 hrs to assemble. You can also buy a Megasquirt II already to go for about $100 more.
Be prepared to do alot of reading and seacrhing for info if you build it yourself. There is plenty of info on the engine that you are using.
http://www.diyautotune.com/catalog/megasqu...-kits-c-30.html

Bob

The stinger is expensive, but seems to be simple. My local suby engine dyno expert guy basically refused to touch the link and recommended the AEM until it showed him the Stinger website. He even had more positive thigs to say about the Megasquirt as far and the car running properly. I have a EMS Stinger in the garage waiting to go in but I should probably plumb the radiator lines and get the rear suspension welded back in before I concider getting the engine running.

Outfront will set you up though. I promise that if you give them a call, they will answer all your questions and will know more about your engine that you can imagine especially if it is JDM. I have had nothing but a great experience with them. I even got a Christmas card from John with a pic of his suby sandrail doing a wheelie across the dunes. Not the cheapest or most expensive option, but after over a year of debating all the options I chose the stinger. John even convinced me that I could build my own harness.

I used to have a Subaru STI as a winter beater and used the original ECU and a Cobb Accessport with software (great piece of kit) which allowed me to tweek any way I wanted, would think this would be your cheapest/easiest option as easy to find on ebay used.

thanks for all the responses, currently im looking into the megasquirt system. problem with rebuilding a stock harness, i dont have a stock car to pull the harness, and seeing how the dismantlers remove their stuff, it doesnt look promising from them either. other option would be to go and remove it myself but im not sure about that yet. hoping i can get megasquirt to run, trying to do my research before i purchase it.

if you can get the harness get the connectors... If you do the megasquirt you can build the harness from there

I decided on the outfront ems stinger. It is a proven system that is truly plug-n-play, comes with a base map that is 95% tuned for your motor. Outfront is using these every day in their sand cars and the gains they say they are getting over the stock ecu on na ej22 and ej25 motors is huge. Their service and support is top-notch. I'm just finishing connecting the harness to my car, almost ready to fire up.

I'm really intrigued by the diy megasquirt route and will eventually take the plunge on my next build. But I'm curious, once you get the system built and tested, then installed in the car, what next? For a newby that knows nothing about tuning do I mess with it enough to get the car running, then take it to a pro for a dyno tune? Or is it realistic that you could learn to tune it yourself without the expensive dyno time? Stupid questions I know, but I can't find the answer in any of the MS info so far.

Does a autotune when driving. Seems to get real close real fast. You can also datalog while driving and then do a review that does a tune. On the new MSIII the logging is done on a SD card so you don't need to have your computer connect when driving.

Bob

Very nice, I need to research the autotune features. So would you ever want or need to do a pro dyno tune?

All you really need with the Stinger is the injector sub-harness. The injector sub-harness unplugs from the main harness right near the intake manifold and unless the previous owner pulled the sub-harness from the injectors and underneath the manifold, it might still be there. Just unplugging it and leaving it would be the easiest thing for a dismantler to do. If you don't have one, you need to go get one for every ECU option that I can think of.

Outfront has a pretty simple drawing on what wires off the Stinger go to where on the engine.

Don't shoot me if I'm wrong, but I don't think Cobb makes accessports for anything older than 2005'ish 2.5 liter Subaru's. I had one on my WRX and is was a very good and simple way to make power, but he would need every wire in the harness from the engine down to the ODBII ports, including the stock ECU.

Here is a great book to get before you do any install. Its a general book about Fuel injection




Performance Fuel Injection Systems HP1557: How to Design, Build, Modify, and Tune EFI and ECU Systems. Covers Components, Sensors, Fuel and Ignition Requirements, Tuning the Stock ECU, Piggybacction

Written by the guys at DIYAUTOTUNE.
It covers all makes of control.


Bob

Thanks just what I need.

My son has a 04 sti and does his own open source tuning. His car has aquamist and a very built motor. He also uses speed density. For a 914 suby he still thinks the wrx ecu is way smarter than any standalone but tuning it is a bear. Course his car is drive by wire and has cam timing which adds a lot of complexity. The relearn part of a stock ecu can really add a lot of complexity to the hotrodding of the stock ecu. It will constantly re time the ignition spark, injectors and cams as it is operating and if there is a glitch it gets complicated. He rides around with a laptop in the pass seat a lot. Just the variances of the quality of fuel is a concern. The part about the sandrails that is in my mind is they are simple and light and toys not dd so I'm not sure the control on those motors is as complicated as a street car with ac and the things that a street car does such as lugging and so on.

At some point I may go standalone for the reasons that others have done it though. It's not cheap but pretty simple and clean. Before the link I probably will try ms.