I'm thinking about doing an engine swap. I did a search for "engine swap" and didn't find the answers I was looking for.

What I have is a 94 F150 with factory MAF 5.0. I'm looking at swapping to a 5.8 from a salvage yard. From what I've read here that it's pretty much plug and play, but I'm a novice mechanic at best. I do my own maintenance, oil changes and such. I've swapped out accessories and I'm not a dumb azz.

What issues can I expect?

specific questions I have are;
1) with my 94 5.0 being MAF will the 5.8 need to be MAF or will my MAF work with the 5.8?
2) Will there be any connection to sensors or sensors themselves that will need to be changed?
3) will I need the ECU from the 5.8 or are they the same?
4)would it be a good idea to get the trans or would they be the same?


Thanks in advance for the help.

 

1)I *think* this should work, your engine won't know the difference. But if you do this you may need to tune the computer. I guess this depends on what, if any, other changes you will have. At the least, you'll need to change the engine displacement the computer uses from 301 to 351. There is a 3 letter code on the computer and that will help you identify if you have one that can be tuned.

3) You can pull the ECU from the 5.8 but it will only do you good if it's a MASS Air computer AND you can tune the computer. If you can't tune it then there's no need.

4) If you have an auto trans...there are some MASS Air computers that can control a transmission. You'll need to identify this by the catch code I mentioned above. If you don't get a MASS Air computer that can control a trans, there are third party controllers you can install and use.

 

Where can I get the code to know if my computer is tunable?

Before I put the 5.8 in I plan on cleaning it up and putting some headers in at the same time but that's about it. If my budget allows I might try my hand at installing a cam.

 

For certain the code will be on the computer itself. oldfuelinjection.com had a list but that site seems to be down now. I can get you a copy of the list when I get home. I am not sure if the code is located somewhere else so you might need to pull the computer to see what it is.

If you are going to put in a CAM and it is a radical one, then you are going to need to be able to tune the computer. You can get away with replacing a cam in a motor as long as the cam isn't too big, then you wouldn't need to tune the computer but since you are also changing engine sizes, plan on tuning the computer, I think you will have better results in the long run.

 

1) There is "MAF" engine per se. As long as you source an EFI 5.8L engine you should be good.
2) There is no knock sensor provision on a 5.8L engine. You can leave that on the old engine or just unscrew it from the old one, but leave it connected.
3) As long as the 5.8L engine is stock or very close to it there is no need to source a computer (PCM) for a 5.8L engine or worry about "tuning".
4) If your transmission is working fine, there is no need to pull one from a donor.

You will need a 5.8L flexplate to mate to the existing transmission. If the donor has the same transmission as your existing truck, snag it. If they are different then you will need to find one somewhere else. The flexplates for a 5.0L versus a 5.8L engine are different.

You will also need to modify the y-pipe to fit the 5.8L engine. The engine itself is slight wider.

 

What about the CID in the computer, won't that be wrong since he is going from a 5.0 to a 5.8?

 

You are the correct, the programmed CID will be wrong but the MAF-based PCM will adapt to the larger engine. That is why I was very specific with my statement "As long as the 5.8L engine is stock or very close to it there is no need to source a computer (PCM) for a 5.8L engine or worry about "tuning"

Once you start adding non-stock equipment then you will be on the edge or beyond of what the PCM can compensate for.

 

OK, so if I am following your line of thinking, you are thinking the long term fuel trims (KARMF) will be able to adjust to the demand?

 

Bingo!

 

thx

Green Griffin 420-
OK, that being the case then, and if you want to use a computer from a 5.0 truck for the 5.8 motor, then the only thing I'd mention is the motor may be a little hard to start/rough running if you disconnect the battery for more than 30 min and reconnect and try to start. The long term fuel trims are something the computer builds and stores as it runs the motor and makes small adjustments to get the fuel ratio correct. Disconnecting the battery for this amount of time will clear out the long term fuel trims which means the computer will need to re-create these if the power is pulled.

This shouldn't be that big of a deal but you will want to be aware of it, especially if you every have to take it to a shop and they disconnect your battery. When they start it up again it will run rough and they'll try to find something to replace to fix it.

 

Here are the computer codes I mentioned...

 

I'll probably get the PCM if mines not tunable. Long term I will do some mods. I'll let you guys know what I come up with.

 

RIKIL after going through that list, it seems as though all the 5.8s have an E4OD trans. Mine is a 4R70W trans. Is that an issue?

 

Honestly, I don't know. We'll have to wait for someone else to chime in.

Do you know the catch code of your computer now?

 

Trans doesn't matter in this case, the 4R70w is more than capable of handling the extra torque output of the 5.8 and it uses the same flexplate as the AOD so you just need a 28oz AOD flexplte to mate the two together.

Any MAF PCM is technically tunable but you will need find out is what batch code family it belongs to, if it's one of the families that have been mapped(decoded) then it will be compatible with tuners like the Quarterhorse and Tweecer. Figuring out the family starts with the calibration code which is usually found on the side of PCM connector so it will need to be pulled out to see it.

Overall a 5.8 swap is very much plug and play in a MAF truck no wiring or hardware changes necessary with a '94+ 5.8 motor.