Swapping Computers = Power????

Skooter

Founding Member
Jul 13, 1999
375
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0
DFW, Texas
I heard from a tech at a local Mustang shop that if you switch your computer out for a '93 computer that you could instantly gain hp. Is this roughly true? Here's my story.....I installed the GT40 longblock crate motor from Ford which is rated at 345hp. That should roughly translate to 270-290 rwhp. I put my Stang on the dyno and all they could get out of the pony was a mere 233 rwhp!?? What gives? Where did the 50 extra horsies go? :shrug: Like I said, one shop told me to backdate my computer to a '93 computer and I should get like 40 hp instantly. Anyone ever done any computer switching? I don't know what to do about my drastic loss of hp. The list of current mods are listed below:

Remember the motor is equiped with the X302 turbo swirl aluminum heads.

Thanks a bunch.
 
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Wow, something is wrong, you should be dyno much more than that. What kind of dyno was it and in what gear were the pulls made?

As for swapping to an A9L, some have done it, but for the money you are MUCH better off getting a custom burnt chip, or some sort of tuning devise like the PMS, twEECer, or EEC Tuner. The swap to an A9L is a pretty expensive one, and then your still stuck with a factory unaltered EEC. Do not swap to the A9L, I think it'd be a waste of money.
 
My local mustang shop has been telling me to swap to the '93 computer also. I think it's a waste of time and money. If I was you I would get it dyno tuned. It's like $350 here to get it dyno tuned and burn a chip.
 
zenboy99 said:
A Pro-M tech at the World Ford challenge told me I would gain .2-.3 in ET by switching to the A9L computer. With the only mods being intake and exhaust.


The 93 and older comps had a much more aggresive tune then ours do. So with just the swap, you will pick up some HP. BUT as said above, you are still stuck with a STOCK ford comp, with stock calibrations.

Switching to a a9l is a waste of money, spend it on a tweecer or chip, end of story.
 
Well no one answered the question about the computer being better. Yeah the older computer had a slightly better tune; they mellowed out the 94-95 computers slightly. But it's not THAT big a difference. Even if you dyno-tune a stock mustang ur not talking about a huge hp increase, just a little bit. I agree with killer that it's totally more worth it to get a dyno tune. But I would think something is wrong with ur engine to only get 233hp. Maybe check the dist. timing or something? I dunno. But good luck figuring it out.
 
You will gain some will the a9l but you will gain more with a chip or TwEECer. And the a9l are pricey to switch to. I know you have to buy at least the chip and harness. I priced those one time and it came out to like $500. That's is as much as the TwEECer. And with the TwEECer you and completely tune everything yourself. But if you don't really know that much then it is better to get a custom chip.
 
Josh94gt said:
Well no one answered the question about the computer being better. Yeah the older computer had a slightly better tune; they mellowed out the 94-95 computers slightly. But it's not THAT big a difference. Even if you dyno-tune a stock mustang ur not talking about a huge hp increase, just a little bit. I agree with killer that it's totally more worth it to get a dyno tune. But I would think something is wrong with ur engine to only get 233hp. Maybe check the dist. timing or something? I dunno. But good luck figuring it out.

I'll answer your question based on my experience with my car.

The pcm in the fox bodys are not better, just different.

For example, the A9L gets some of it's info based on rpm where the T4M0 uses load based info.

Most tuners are very familiar with the A9L's cause they have been around for so long.

Don't think you can't turn up the fuel & spark knobs for full kill with the T4M0 or J4J1 like you can with the A9L. You can *** You just do it differently.

I do not claim to know everything about the 94-95 pcm but I do have a basic working knowledge of it that I picked up from various sites.

I put that basic knowledge to work with a Tweecer and was able to take control of the tune for my car and replaced the 94-95 GT program with the 94-95 Cobra program and I got what I think have been good results.

As for retro fitting the A9L, I think, I'm not sure, but, don't you have to also get a MSD box or something extra in addition to all the other stuff to make the conversion? You still have what you started out with, a stock pcm that you can't make tuning adjustments on.

Hey, I'm not saying putting the A9L in our cars won't make more power.

But for me, I did not mind investing some time in learning the basics about our pcm and I put the money toward a tuning device instead of a different pcm and its supporting hardware.

Later
Grady
 
something is wrong with your motor beyond eec limitations. the t4m0 processor alone will not cause a loss like that. i put 230hp down with my stock heads, stock cam, stock eec, and stock maf. this dyno pull was also made with no timing advance. is your check engine light on? if so, what codes are you pulling? is the car hesitating or sputtering? as far as the eec goes, all you will be doing with the a9l swap is putting outdated technology in a newer car. get a tweecer or a chip custom burned to your combo. it will be cheaper, easier, and allow you to make changes when you add to your setup.
 
I bought the GT40 Longblock crate motor From Dallas Mustang who got it directly from Ford. I put on the 500 miles and took it back to Dallas Mustang to get it dyno tuned. 233rwph was the baseline run. I'm not sure what kind of dyno it was but it had one large wheel in the rear and he said it would take up to 1200hp. After the baseline they then began to tweek the car and burned a chip. He made all of the necessary modifications and all he could get of the the car then (with the custon chip) was like 247rwhp. Needless to say I did not buy the chip since it only got me like 14 extra rwhp. They were using AutoLogic to burn the chips. As far as I know I received the correct longblock from Ford. I looked at the markings on the heads and such. I also talked to the Ford techs (for what it's worth) and he said the combo I have should work really well. I'm really bummed about the whole thing. I'm not sure what to do next. Any help is greatly appreciated and thanks for the replys so far.

**Note**
The guys at Dallas Mustang did not offer any help as to what the problem might be. I had just spent about $4000 with them and all I got was 233rwhp!
 
i'm going to have to chime in with everyone else here, i think something is wrong. Who put the motor in the car, you or a shop? If the castings are stamped right then chances are you have the right motor. Check all things stupid because chances are it's something rediculous that's hanging you up. I work on radars for the govt. in my spare time and I know when you do a major swap on anything complicated and expensive it's always the stupid simple things that bite you in the butt... Go back and double check all your numbers and connections, check your plugs, wires, timing everything. It could be a combination of things... Be methodical and you'll find it... Grab a haynes or chiltons or some other automotive book if you have to and retrace all the things that help make power. You have a problem, but it's solvable... start over and i'm sure you'll find 40 ponies taking a break under that hood somewhere...
 
Yeah something is definitely wrong. Have you checked your compression and timing? And what size injectors are you running. I don't know if 19# will be enough for that unless you have an adjustable Fuel Pressure Regulator. Just like grrrrrrr said you just need to check everything those little things will add up add up after a while. What are those engines supposed to dyno at? I have heard like 270-280.
 
I put the motor in myself with the help for a few buddies. It took about 4 days from start to finish. The car started right up when we played with the timing. How do you run a compression check? Do I do it or is it a shop that does it? I assume they do it while in the car???