How Much Can The Stock Ecu Handle In The 95 Gt's?

smithX2

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Jan 20, 2016
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Wyandotte, MI
I am intrigued by the programmers and the thread outlining how and what can be changed. I am currently running a stock lower end with Edelbrock intake, SVO heads, E303 cam, 70mm throttle body, cold air intake, pulleys, no air pump, shorts with an X pipe. 5 speed with a stage 2 clutch, and stock fuel system.
Can more horse power be gained by tunning this set up? I will probably go to a bigger 347 or 351 with fuel injection in the near future, how far do you have to go to "tap out" the stock set up? I don't want to waste the money on a programmer if it will be short lived.
 
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Programmer? If you mean a hand held one..they don't make one for these cars. It's for the newer systems. The stock computer will run fine with most boltons,h/c/i,and 30# or smaller injectors. If you're adding more cubic inches and/or power(especially forced induction) you will definitely need at least a chip and probably should look into a standalone system(megasquirt,Holley,etc).
 
If it idles and runs fine I would say you are ahead of the curve. The sn computers were very temperamental. Steeda and a couple other companies made sn specific cam just for this.
 
So what are the TwEEcer and P.M.S considered? The way I read that thread is you can make physical adjustments to the ECM? What am I missing?
Tweecer is a chip that allows you to edit and modify the parameters through software.

Pms is a piggy back ecu . I run one in my coupe


Sent from my iPhone using my fingers while my auto correct makes me seem illiterate
 
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Currently at 755whp on a tuned W4H0 pcm in my Cobra. Tuned by myself, with a Moates Quarterhorse. I'm "exceeding the limits" of the PCM, but with some digital wizardry... I was able to get much more out of it than it should be capable of.

The 94-95 PCM's have airflow and load limitations that need to be worked around.

Don't let anyone BS you with the "those computers are picky and wont idle" stupid bull:poo:. If the car isnt running right, you had the wrong person tune it.
 
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I actually Hear the picky quote a lot. My idle sucks, after researching on hear I may go new mass and bigger injectors. I thought mabe I could sneak around the mass with the PCM. Figured I could ease into it by buying a piggy back.
 
I actually Hear the picky quote a lot.

Most of the people who will say things like that, do not really understand the inner workings of the 94 - 95 computer. many will also research and find how to's and examples that show you how to do certain things with the fox body, which do not directly correlate to the 94 - 95 cars.

There are several key differences between the two models and the two computers. One of which being the computers dislike for calibrated mass air flow sensors.

I personally have tuned a .630+" lift solid roller cammed stroker, with more than 245° of duration, and an LSA of 109... and had it idling rock solid at 700rpm on a T4M0 pcm.

Hell, my turbo 351w idles smooth at 550, although I raised it to 750... and it's got 96lb injectors.
 
Currently at 755whp on a tuned W4H0 pcm in my Cobra. Tuned by myself, with a Moates Quarterhorse. I'm "exceeding the limits" of the PCM, but with some digital wizardry... I was able to get much more out of it than it should be capable of.

The 94-95 PCM's have airflow and load limitations that need to be worked around.

Don't let anyone BS you with the "those computers are picky and wont idle" stupid bull****. If the car isnt running right, you had the wrong person tune it.

Man it's obvious you know your stuff, but let me point out that your posts come across as very harsh sometimes. It's a lot easier to respect a smart guy when he's not calling someone an idiot or saying bull**** about someone's statement. That's all. Have a nice day.
 
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Man it's obvious you know your stuff, but let me point out that your posts come across as very harsh sometimes. It's a lot easier to respect a smart guy when he's not calling someone an idiot or saying bull**** about someone's statement. That's all. Have a nice day.

who did I call an idiot?

The whole idle issue and "finicky computer" crap is all bad info. Much like setting your TPSv to .98-.99v... Its been disproved time and time again, yet the same crap gets regurgitated day in and day out.
 
The whole idle issue and "finicky computer" crap is all bad info. Much like setting your TPSv to .98-.99v... Its been disproved time and time again, yet the same crap gets regurgitated day in and day out.

Not my point. I think I was pretty clear.
 
Hell, my turbo 351w idles smooth at 550, although I raised it to 750... and it's got 96lb injectors.

96lb injectors on a factory computer? How did you accomplish this? Honestly, I want to know how this was done. I've heard of people going as high as 36lb injectors, but the general consensus is that the factory computer fries after that.

To the OP, I've always heard that the injector was the limiting factor on the stock computer. It's not the issue it used to be. DIYautoTune makes a complete computer that plugs into the factory harness on a Foxbody at a very reasonable price. It is essentially a MegaSquirt setup, and you can do almost anything with it. I seriously doubt it takes much more effort to adapt it for an SN.

Kurt
 
96lb injectors on a factory computer? How did you accomplish this? Honestly, I want to know how this was done. I've heard of people going as high as 36lb injectors, but the general consensus is that the factory computer fries after that.

To the OP, I've always heard that the injector was the limiting factor on the stock computer. It's not the issue it used to be. DIYautoTune makes a complete computer that plugs into the factory harness on a Foxbody at a very reasonable price. It is essentially a MegaSquirt setup, and you can do almost anything with it. I seriously doubt it takes much more effort to adapt it for an SN.

Kurt
It's not that hard. The ECU will accept 114# injectors if it's programmed correctly.

Hell, if I tried hard enough I could probably run 2150s.
 
Careful guys, allot of these solutions suggested are not plug and play and many threads here attest they are very difficult at best. OP I am not a tuner, however if you live near a good tuner with a dyno you can gain allot by an addin chip to the stock ECU, tuned specifically to your set up
 
I can't say on the 94-95 cars but i can for sure say the fox cars can't do the big injectors. From what I understand, the larger injectors have a different impedence coil and require a stronger driver. You may get away with it for a little while, but eventually it will fry it. The standalone systems are designed for the extra ohm load.
 
The stock ecu will not accept low impedence injector. you need high impedence injectors so you do not burn out the injector drivers. the stock ecu can accept 11-14 ohm injectors, for the 4-6 ohm injectors you would need an add on resistor box.

even the aftermarket ecu requires low impedence drivers to be built. trust me I know, I built my own.
 
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The stock ecu will not accept low impedence injector. you need high impedence injectors so you do not burn out the injector drivers. the stock ecu can accept 11-14 ohm injectors, for the 4-6 ohm injectors you would need an add on resistor box.

even the aftermarket ecu requires low impedence drivers to be built. trust me I know, I built my own.

Maybe i should have said, "different ohm load," not "extra." I knew there was a difference. Just couldn't remember which direction.
 
I can't say on the 94-95 cars but i can for sure say the fox cars can't do the big injectors. From what I understand, the larger injectors have a different impedence coil and require a stronger driver. You may get away with it for a little while, but eventually it will fry it. The standalone systems are designed for the extra ohm load.

So, trying to be as nice as possible... I'll comment on this post.

Since I love accuracy of information, I decided to go out into my garage and check the resistance of my current injectors. http://fuelinjectorclinic.com/mustang-gt500/IS404-1100H

They ohm out at 11.8 ohm.

In order to make the best comparison I possibly could, I grabbed a set of 03/04 Cobra injectors that I have laying around... and checked them.

14.8ohm [emoji6]

I then decided to check Fords parts catalog. Which is where I found...

de0ab06ab86198cd56dbcf566078e44c.jpg


As you will see, the "high impedence" style injector is normal for us. Several years ago you needed would use a low impedence injector for the very high flow rates that were necessary for high performance cars. These required special drivers, or added resistor packs, to be used in cars that required high impedence injectors.

Fast forward to today... you can get 200# injectors that are still the proper resistance spec for our cars.
 
the highest number I see on those charts is 42# for the high impedence injectors.

that said I recently bought a set of 50lbers from ford that are high impedence. at some point the resistance must change [low impedence] to get a proper flow rate. but you are correct as of today there are many options available.