5.0L non HO to HO
 

I have recently swapped my non HO EFI motor for an HO EFI and found my new motor has a new firing order. I am using the original intake,fuel rail and injectors. I assume my injectors will not be pulsing at the right time. Can I move the injector connectors to the proper injectors to correspond to the new firing order? Will this work or do I have to hunt down another EEC unit ?The old firing order is: 1 5 4 2 6 3 7 8
The new firing order is 1 3 7 2 6 5 4 8
This is my plan:
injector connector 5 to injector 3
connector 4 to injector 7
connector 3 to injector 5
connector 7 to injector 4
Will this work and if not why not?
Thanks for any help
TOM

Check out www.coolcats.net and go to their tech section. If you can't find what you're looking for there, email their webmaster, Eric. He can help you with HO conversions and swaps. I'm sure you'll find some useful info on that site also. I would think that your plan would work, but personally, I would get a wiring diagram of the EEC connector (I have found one at the public library on microfilm before) and just swap the pins for the #5 and #3 injectors, and then the others. But check out that website first.

It will be a re-wiring nightmare without a 5.0 HO ECU. A ECU is about 50-100 bux at a junk yard thats the route I would go.

non HO efi is batch fired, HO 5.0's are SEFI. There are several differences, and you must change the ECM, otherwise you will have a very rich running engine.

what does batch fired mean? and what are the other dfferences?

I Think he means one bank of injectors are injecting fuel at the same time (batch fired) and on the SEFI, each injector is opened independently.

Just swap a computer and wiring harness, no biggie.

also try www.pro-flow.com for more info.

You don't need to swap the harness, To make an non-HO to an H.O you need:

1)Swap the harness if you want mass air
2)Swap the EEC
a) If you don't swap the engine harness for mass air get an speed density EEC
b) If you swap to mass air get a mass air EEC .
3) Swap the cam
4) Change to 351 firing order
5) Swap injectors to 19's or bigger with match maf(if mass air)
6) Swap heads to E7's
7) Swap intakes, you want one from an 87-93

I did this swap on my brothers 88 T-bird with a 302 with all my stock 88GT parts.

Yes, you do need to swap the harness. Batch fired injectors have 3 wires going to the injectors; a common hot wire, and a signal wire for 2 sets of 4 injectors. It is impossible for the ECM to sequentially fire the injectors unless each one has it's own signal wire.

The attached picture is the schematic for a non-HO 5.0. Look at the injector wiring.

This attached picture is the wiring schematic for an HO 5.0. Again, check the wiring for the injectors.

When I did the swap on my brother's 88 bird all we did was swap the upper half of the motor, cam, EEC and injectors and used all the existing wire harnesses. Didn't swap any harnesses and the car ran fine. I am just saying how I did it and it worked fine...Not saying who is right and wrong here..

You don't need your 5.0 HO to be sequentially fired. Replacing the harness is not nessisary for it to run good. My cougar's HO converted 5.0 pulled harder than all of my friends stock 5.0 mustangs. It may be batch fired, but they will run hard.

Was this felt on a "butt dyno", actual dyno, or track?

Well, it was extremely rich, too. I hope you change your oil frequently.

:)

wires to injectors
 

OK I have two wires going to each injector. So they must be sequentially fired right? How could injectors be batch fired? some of them would be firing on the exhaust stroke. What does the fuel just sit in the manifold til the intake valve opens and it gets sucked in?So I have change the computer, dont change it. Change the harness, dont change it. Use the old firing order,use the new firing order. Im going to change four wires in the ECC connector and see what happens. Should be ready to fire up this week.

Re: wires to injectors
 

That would be my understanding. Maybe PKRWUD can enlighten us on this concept?

Nope, wasn't too rich, ran great, no problems with the motor at all.

Cougar weighed in at a mega heavy 3600 pounds and went 14.5 at 97 mph with a T5 and 3.55's in back, 2.0 60 foot was the best i could get out of it. The motor didn't run rich or have any other problems, I'm telling you guys, go to www.coolcats.net, people on that site do the HO conversion ALL THE TIME, and they may end up with a batch fired 5.0, but it runs hard, and has no problems with the stock non HO harness. Trust me, it's been done, and it works.

Re: wires to injectors
 

Batch fired and sequentially fired injectors both have two wires going to each injector. Check the color of the wires. If each one has a common color wire, and a different color wire from all the rest, then it is already sequentially fired. If it has a common wire color for all 8, and then another common color for one bank, and a third common color for the other bank, it's batch fired. See the images I attached before.

Batch fired, known by Ford as Multiport Fuel Injection (MFI), sends fuel through the injectors in groups of four at a time. Right bank and left bank. The intake valve only opens once during each of four strokes, and that is when the accumulated fuel enters that cylinder. To keep the engine from running extremely rich, one of two measures is taken; either 14 pound injectors are used, or the pulsewidth is greatly reduced by the ECM. It depends on the application. This is why the ECM, the wiring harness, and the injectors should all be replaced.


Then you should write a book. You've figured out how to do something that scientists and engineers the world over couldn't.

Listen man, if you're so smart, think about it, one of two things is happening when people swap HO computers and injectors onto the harnesses in the 80s cougars.

1. The motor ends up MFI or batch fired as you call it, and each bank is fired by one of the pins on the computer which is used to fire one of the HO's individual injectors. So the fuel sits in the intake port for a fraction of a second before the valve opens and draws it into the cylinder. There is the same amount of fuel being delivered as in the sequentially fired HO engine, so if you think it would run rich just because the fuel would sit in the port for a little longer, you're wrong, because it does that in the MFI setup too. The reason they have 14# injectors instead of 19# is because the upper intake is different, the throttle body is smaller, the cam is a lot different, the heads are different. They all flow less air which means less fuel is needed. The 14# injectors are not because it is batch fired.

2. It is possible that the diagram you have is for certain non HO engines and that the cougar's non HO engine harness is sequentially fired. This is probably the case, because the intake plate on top of the intake says "Ford 5.0 - SEFI" which stands for Sequential Electronic Fuel Injection. This is probably what is going on. The harnesses on cougars, t-birds, and probably crown victorias from 1986 up to 1994 which is when they started putting the 4.6 into cougars and t-birds, were all SEFI. I donno what engine that diagram is from but all of the non HO engines that I know of (are they used on another vehicle?) are SEFI.

Anyway, if they used the non HO on another car and it was MFI, then you might be right, maybe the car wouldn't run perfectly, but i still don't think that a batch fired 5.0 would run bad. The air/fuel mix would be good because the pulse width for each injector is exactly the same as if you were running SEFI, they just all fire at one time. But when you're talking about an engine where each cylinder is firing more than 7 times a second. I don't think the fuel is going to collect on the walls of the port if it sits for 1/7th of a second or less. I may be wrong, you may be right.

First off, he never said where the non HO was from.


Wrong. It would make a huge difference. That's why the batch fired systems work the way they do. If what you're suggesting would work smoothly, don't you think they would have done that? That's why I said you should write a book; you've figured something out that they couldn't. As far as the injector size, I've got a '95 4.9L that is batch fired, and it has 14 pound injectors. My buddy in Valencia has a '96 with Sequentially fired injectors, and he has 19 pounders. His cam and intake are identical to mine. Under the same pressure, a larger injector will flow more fuel with the same pulsewidth. Since the injectors are only being pulsed once every 4 strokes, versus once every other stroke, the injector size was increased. If they simply changed the pulsewidth, they would run into problems at higher rpms.


All of the 5.0's used in Ford trucks and vans were non HO until '93. Every single one was batch fired. After '93, they were HO engines, complete with SEFI. The Crown Vics used everything. Even the police Crown Vics through '91 still had carbs, and didn't use any fuel injection. There were many possible combinations a person could come across, but the best plan for converting a non HO to an HO is to replace the ECM, the injectors, and the harness.

its an HO from an '86 mustang supposedly. It has a casting # of E6SE. I know the S is supposed to be t-bird. But by watching the lifters I can tell the firing order is 13726548. So I assume its HO right?