Guys, in my quest to be stubborn, ive happened across some infor on the web about a DA1 computer out of a Speed Density 5.0HO mustang. Does anyone know if that computer is different than the one in my 86' F150 Speed Density 302?

If I could get a hp/tq bump out of swapping in a mustang Speed Density computer I might try that before converting to MAF.

I cannot find any definitive information on whether or not its programmed more agressively than the truck computer or not. Thanks for any help.

 

I am sure it's different. The 302 truck engine is not a mustang engine. Different intake, different camshaft with roller lifters, etc. I do not think the mustang computer will turn your truck engine into a mustang engine, and I do not think you want it to turn into a mustang engine. The mustang is a very light car while your truck is a lot heavier. That's part of the reason for the different intake style.

 

Mustang, Crown Vic, Grand Marquis, Town Car, Thunderbird SD computers are sequential injection rather than bank fired like a truck. You would still need to rewire some things to make it work.

 

If a Mustang engine has higher hp and torque output in all rpm ranges then why wouldn't I want to have a mustang motor in my truck? I understand the cams and lifters are different, intake and everything else. But Ive never understood why people say what you just said. I mean think about it...you just told me my 185hp truck engine is better in my truck than a 200hp mustang engine that has more torque. Would you care to explain this a little further, maybe I just don't understand something basic? Thanks.

 

Sequential firing would be much more efficient and would give me an advantage correct? I have to re-wire/re-pin my stock harness for the MAF conversion. But if I can get a Speed Density computer that has sequential injection versus bank fire that would be one positive step forward correct?

Would I not see gains in HP and Torque if I used a mustang Speed Density computer?

 

Subscribed, but nothing to add. Just wanting to learn.

 

It might help. I re-sequenced the injectors on my truck from the factory grouping of 1,4,5,8 and 2,3,6,7 to 1,4,6,7 and 2,3,5,8 like the 180° manifolds and the TBI systems. So far it runs about the same, but seems to have improved the fuel economy from 10.5 or so to 11.7. I did make sure #1 is still triggered as it was before on the Inj #1 pin.

 

Bill, thats a bit confusing to me. Care to elaborate? Why would you do this? Are you saying yours is a bank fire SD setup and you are telling one injector on the other side to fire with three on one side? How does this help?

 

It's not 1 cylinder on one side and 3 on the other. It's the middle two on one bank and the outer two on the opposite bank. Like he said, it's just like a 180* carb manifold.
As for the mustang vs. truck... yes the 'stang has more hp and tq, but I'm sure both require a higher rpm to achieve than the truck motor. The truck motor will make more torque at lower rpm than the 'stang motor. Keep in mind, the truck computer is designed to run your engine as built, and the same for the 'stang computer, designed to run a 'stang motor. The computer will likely not help your engine a bit, but make it run worse, unless you put a 'stang engine in your truck. The comp. ratios and cams are different, and w/SD this will not work to your benefit the way you think it will. Put a chip in your computer, run a free-flow exhaust, and do a "six-liter" tune on your engine. Much better results...

 

Because, your engine makes more torque at lower rpms where a truck needs it for pulling. I don't have a source for the numbers to back this up, but I am confident enough to stick my neck out and say I am right. If you wanted to changed the gearing in your truck, you might get some advantage with a mustang engine setup.

 

The biggest mistake people make is to think "high performance" as in 5.0L Mustang GT engine. It gets more horsepower and torque but at a higher RPM. It is torque that does the work.

FWIW, horsepower is figured by torque X rpm to get the 1 HP = 550 ft-lbs/sec. If the engine is capable of generating reasonable torque at higher RPM then you will make more horsepower. Honda engines are a good example, they can make a lot of power at high rpm, but almost no torque below around 4000 rpm. Truck engines are built for low end power which is why a 300 is a better truck engine than a 302.

 

Kinda sounds like my brother's Taurus SHO, with what I call a 6-cylinder, Yamaha-built, Motorcycle Engine.

It's got almost zero power below ~3,000 RPM, (ask Gary, he drove it) but ya hit its power band at ~3,500 and the thing redlines at 7,000 RPM and it becomes really fun, kinda like a motorcycle once you learn how to drive it.

But a Taurus is lots lighter than a truck and can do that.

 

Okay guys. I understand all this. It would be interesting to see a side by side dyno chart of a stock 5.0 truck motor vs. a stock 5.0 stang' motor. Just to see where torque comes in.

Franklin, I will say you are probably right, but I will also say this....a stock 86' f150 5.0 is totally anemic in power down low.

I have done a true dual h-pipe exhaust with turbo mufflers. I have also done the ignition upgrade and timing bump. The stock E7TE heads are also slightly massaged out especially on the exhaust side. I had a gt40 exhaust port profile that I used to try to get close to the gt40 head.

I guess the only thing left for me to do is upgrade intakes and do the MAF conversion. I almost have all the parts, just need an A9P ECU, speed sensor, and a different intake tube to adapt the MAS to.

 

Bill, is there a How-To thread on here explaining how to do this? I would like to try this if all I need is some wire and solder and an afternoon. Thanks!

 

Ray, there isn't a "how to thread" for this. What I have done, if you look at my thread https://www.ford-trucks.com/forums/1...n-86-f350.html
You will see that my long term plans are to convert to MAF SEFI using a WAY1 EEC from a 302 Bronco w/E4OD. The E4OD gave me my biggest problem since only truck EECs have the needed circuits.

The two injector banks are 1,4,5,8 tan with orange stripe and 2,3,6,7 tan with red stripe. The individual injectors are wired as follows:
Injector #1 555 tan
Injector #2 556 tan with white
Injector #3 557 tan with yellow
Injector #4 558 tan with black
Injector #5 559 tan with light blue
Injector #6 560 tan with light green
Injector #7 561 tan with orange
Injector #8 562 tan with red

All are fed by a red wire, circuit #361, numbers after injectors are the Ford circuit numbers. There are two junction splices in the engine harness that you will have to undo, they are probably going to be next to impossible to undo without cutting. The easiest way would be to find an engine harness from a 94-96 302 automatic, it is set up for sequential injection form the factory.

One item you will run into if you change to a newer than 86 truck EEC, the EGR control system changed completely in 1987.

When I built my engine harness, I had some 302 stuff that came with the Bronco EEC and partial front harness and some stuff from a 4.6L engine. Between the two of them and a spare 460 engine harness, I was able to build one that would plug into the 92-96/7 style 42 pin connector by the power distribution box. I wired all the injectors to the appropriate pins for a 95 302 w/automatic, then built jumpers into the currently installed 1993 front harness to gang the injectors in their banks. To change the way they were ganged, was a plug and play item for me.

You might want to maybe add a jumper in the injector wiring with a pair 8 pin weatherproof plug/socket combinations that you can use to easily change injector ganging or go to sequential easily.

I hope I haven't confused you too much.