Hacking/tuning the jeep ecm

[1project2many]

I'd use a 7730 myself. Lots to gain by switching to an ecm you can adjust.

But the Mopar stuff looks kind of neat. I found an article a while back describing the ChryCo approach to fuel and spark and I was trying to find it again. While GM took to making tables, Chrysler used functions. So they've got "ramps" for spark and for fuel based on coolant temp, rpm, iat, tps, & etc. After working with cells and specific rpm/map intersections the Dodge approach seems lacking but when you think about the VE smoothers and the way many people fill in spark and VE tables, we do the same thing.

Was a guy a long time ago who swapped a GM ecm onto a Jeep I6. Was one of the first ones I know of. I think it was Jeremy Gonyou, same guy that got a job at Ford by reverse engineering GM code. :) Can't find any references right now but it wasn't a bad project for something done back in the dark ages.

[JeepsAndGuns]

Megasquirt looks like a very nice system and I have nothing personally aganst it. But in the back of my mind I just dont want to run a fully custom ecm. I cant help but thinking if something freak happens and the ecm get fried (bad alt, idiot hooks up booster cables wrong, many things could happen) I am now stuck with a jeep I cant drive untill I order a very expensive replacement. If I use a common junkyard sourced ecm/pcm, if something happens I could go into most any parts store or junkyard and get a replacement, I can also buy and keep a couple of spares.

Looking on tunerpro at nothing but the dowload page, I saw a couple V6 ecm's that are supported. (but didnt dl and look at the definations) Plus I dont know much about these engines either.

16196387

1FA.xdf

1FA.ads

94-95 3.1L (L82) A-body (Century, etc) ADS also spplies to W-Body

16183247 16197428

V5 ONLY - 5B.xdf

V5 ONLY -5B_V5.adx

94-95 Series 1 3.8L (L27) and 94-95 Series 3.8L SC (L67)

16196401

2E.xdf V5 ONLY - 2E_tpv5.xdf

2E.ads

94-95 LQ1 3.4L V6

[EagleMark]

Megasquirt looks like a very nice system and I have nothing personally aganst it. But in the back of my mind I just dont want to run a fully custom ecm. I cant help but thinking if something freak happens and the ecm get fried (bad alt, idiot hooks up booster cables wrong, many things could happen) I am now stuck with a jeep I cant drive untill I order a very expensive replacement. If I use a common junkyard sourced ecm/pcm, if something happens I could go into most any parts store or junkyard and get a replacement, I can also buy and keep a couple of spares.

Looking on tunerpro at nothing but the dowload page, I saw a couple V6 ecm's that are supported. (but didnt dl and look at the definations) Plus I dont know much about these engines either.

16196387

1FA.xdf

1FA.ads

94-95 3.1L (L82) A-body (Century, etc) ADS also spplies to W-Body

16183247 16197428

V5 ONLY - 5B.xdf

V5 ONLY -5B_V5.adx

94-95 Series 1 3.8L (L27) and 94-95 Series 3.8L SC (L67)

16196401

2E.xdf V5 ONLY - 2E_tpv5.xdf

2E.ads

94-95 LQ1 3.4L V6

There's lots of choices for an GM ECM ready to go for 6 cylinder and well supported by TunerPro. Numbers go down because you want to replace/repin yours and use existing location under hood. The perfect choice is 1227727. But it is not sequential. Only one I know of that is under hood and sequential OBDI is for an LT1 16188051-16191333-$EE But it's for 8 cylinder, even if the PCM could do six cylinder building a six cylinder OptiSpark distributor would be mind boggling.

Now if you would just forget about sequential and run a batch fire ECM the answer is simple. 1227727 GM ECM used in many six cylinder under hood cars.

It made me remember a conversation with a Detroit Fuel Injection engeneer who has been working on developing EFI from it's inception for GM then Ford. Sequential FI was developed to meet EPA standards for idle and off idle. The way he described it was once an engine reaches like 1200 RPM it does not matter, injectors are firing so fast it does not make a hill of beans. More RPM and they hardly flinch at turning off, high RPM and they are just about wide open constantly. So why is SFI such a big deal?

[JeepsAndGuns]

The factory ecm is underhood, but I wouldnt ignore anoher option if it was a under dash unit. It wouldnt be much more work just to run some extra wire and mount it inside. Whats the datalog speed on that ecm? If my plan for tuning my factory one bombs, then I would want at least the same datalog speed at the 7427 I have in my cherokee, or faster.
Also, It would be nice if I could reuse as many of my factory sensors as I could. I already have a 1x cam sensor, and it look a lot like the gm ones I have seen pictured on here. Its also a speed denisity (MAP) based system. I think DIS would be a added plus, if possiable. I dont really want to swap to a older modded non FI distributor, I would want a crank triggered system. I know my factory crank trigger would not work, as the notches in the flywheel wont match up to anything gm uses. But my harmonic blalancer has a nice lip around it that would lend itself to being machined real easy.

[EagleMark]

1227727 is the same as your 97427, even the memcal looks the same. It is an underhood weather proof version of the 1227730 that looks like your 97427.

Not sure about all sensors, when I checked the 2001 to 2004 4.0L tuned port intake it looked like TPS, MAP, IAC and injectors would work. I had one for an old 258 I was going to do a 4.0L HO head on.

Never checked the Jeep distributor because I was going to do this:
http://www.gearhead-efi.com/Fuel-Inj...BI-Conversions!

If going to DIS jeep has a distributor with just a cam sensor on top, no cap...

[Alioth]

The SBEC2 in the pre-OBD2 4.0 HO also acts as a TCU and as a stone age body control module. You like your power door locks (y/n)? You have to retain it on some level, even if it does not control the engine any longer, or else rewire the entire vehicle. This means the odd 8v volt Chrysler triggering pattern needs to be retained, too, for AT vehicles. Transmission control is relatively straightforward if AT as the AW4 is the A340x in Toyota products (Supra/Taco) is whatever Volvo called their flavor of the Aisin-Warner slushbox. If push comes to shove, the AW4 is easily controlled... I don't have the link handy, but one guy on the Jeep forums set his up push button style a la Edsel. :P

B&G can tune the SBEC2, they have screenshots of Tunerpro on their website. Gut feeling says they took some of the turbo Dodge ECU knowledge, and were kicked info from one of the large tuning companies that decided not to pursue older vehicles. http://www.bgperformancepcm.com/

I'd like to tune the stock SBEC2, personally. The 411 PCM is also cool, but there's something elegant about not having to invent cam/crank pickups. MS1/MS2 is a your mileage may - and will - vary proposition.

[EagleMark]

Sure sounds like that Piggy Back tuner would take care of any engine mod tuning you need without all the other issues with tranmission and body control issues...

[JeepsAndGuns]

The SBEC2 in the pre-OBD2 4.0 HO also acts as a TCU and as a stone age body control module. You like your power door locks (y/n)? You have to retain it on some level, even if it does not control the engine any longer, or else rewire the entire vehicle. This means the odd 8v volt Chrysler triggering pattern needs to be retained, too, for AT vehicles. Transmission control is relatively straightforward if AT as the AW4 is the A340x in Toyota products (Supra/Taco) is whatever Volvo called their flavor of the Aisin-Warner slushbox. If push comes to shove, the AW4 is easily controlled... I don't have the link handy, but one guy on the Jeep forums set his up push button style a la Edsel. :P

B&G can tune the SBEC2, they have screenshots of Tunerpro on their website. Gut feeling says they took some of the turbo Dodge ECU knowledge, and were kicked info from one of the large tuning companies that decided not to pursue older vehicles. http://www.bgperformancepcm.com/

I'd like to tune the stock SBEC2, personally. The 411 PCM is also cool, but there's something elegant about not having to invent cam/crank pickups. MS1/MS2 is a your mileage may - and will - vary proposition.

This is in a soft top manual transmission jeep wrangler. It controlls nothing but the engine.
I have forgotten one thing. It also regulates the alternator. But that wouldnt be hard to bypass, as there are kits to convert it.
I too have come upon BG preformance while googleing. I shot off a nice lengthy email to them explaining my situation, and my desires, and asked if they had any options, or knew of any. That was monday, I have had no response. I have a feeling I wont get one. Mabey I should call.


Eaglemark, I have one of those cam sensors from the 99 and up 4.0. I picked it up at the pull a part for cheap. The engine I got it from was stripped to the block and the cylinders got rained in. That cam sensor was about the only thing left on it that was good. I got it and the wiring pigtail. Not really sure why I got it either, but I did. Its basicly a distributor cut in half and the sensor stuck on top. The stock 91 and up 4.0 dist has nothing in it but the rotor and 1x cam sensor. I can take a couple pics of mine if you want to see it. Sometime around 94 or 95, they changed it slightly, and moved the sensors location inside the dist to where it can be replaced without removeing the dist and removing the gear and shaft from the housing.
99 is when the 4.0 went DIS. Its also when they changed the intake manifold design. The 99 and up intakes are a popular swap onto older 4.0's for a slight power boost. I have one here but have just been too lazy to swap it on and see for myself.
I looked at the 7730 on ebay and it doesnt look anything like the 7427. The plugs are on the side, the memcal is in a diffrent spot, and there is a 3rd yellow plug. What goes there? The 7727 has 4 plugs. What defanition would I want to use, I saw like 3 or 4 on tunerpros webside. Were they ever used with DIS? And also, what datalog speed are they?

And last, I stumbled across this. Seems rather interesting.....
http://www.thirdgen.org/techboard/di...-ls1-pcms.html

[Shawanda]

I have, and looked through the gel with a flashlight, and its a 27c256 eprom in it, with the little picture of texas on it, also has a sticker covering the window and a bunch of numbers on it. There is a setting in the moates prom I/O for that chip. So I'm thinking it could be read jeep ecm's also have a 7 diget number on them, with the last 3 being twice the size of the first 4.

[1gcrazy]

I have an ibox. No idea how to use it.