I have a 1990 F350 with a 5.8 liter. I recently aquired a 95' 5.8 HO and was hoping I could swap the two. I am slightly concerned about the wiring differences if any and also about the difference between the stock and HO. If anyone has any insight I would greatly appreciate it. Thanks in advance.

 

Who told you it was a HO? there's really no such thing. The '95 motor does have a different cam than your '90 and it does generate a little more power but otherwise it is identical so it will swap in no problem.

 

Thank you for the input. The guy I got it from told me it was an HO. I did some reading and thought that the firing order was different because of the mild cam which he said he installed. I have read so many different things on the internet that I decided to go to the site with the people in the know! I was not sure if the wiring harness and computer from the 90'
would run the 95'. I do have the computer from the 95' but was also not sure if it would operate properly on the 90' harness. I want to have the least amount of trouble possible and get the truck back and running as soon as possible before the snow flies. I really appreciate the insight you are giving me. Thanks again!

 

There is probably not much to be gained by switching to the '95 PCM. Plenty of info here: Ford Fuel Injection EEC Program Codes Ryan has a pretty comprehensive listing of EEC-IV program codes. The wiring for most trucks did not change from 1987 to 1995. Your F350 did not change to Mass Airflow until the Super Duty came out in the later 90's. The F150/Bronco did change over from Speed Density to MAF ~1995. So unless the PO of your engine actually has a MAF version EEC-IV you will not see any appreciable difference from your existing PCM and the newer PCM.

 

The PO changed the cam? You need to find out exactly what cam was installed then, was it a 5.0HO cam and hence the reason he told you it's now a 5.8HO, or was it some aftermarket cam? The 5.0HO cam is good and is compatable with the truck EFI systems, but many aftermarket cams are not.

Also note that if the '95 PCM is from a mass air F150/Bronco is it not compatable with your '90 wiring harness, the mass air motors use sequential injection with an independent wire for each injector(9 total with power), while the SD system fires them in batches of 4 so there are only 3 wires total. Firing order on the 5.8 never changed either but it's tied to the cam and all Windsor family motors take the same cam so it is possible to use a 289 or 302 cam with the old firing order.

 

Thanks again for all the info! I need it. The motor came from an F250. I have called the former owner to find out if the cam he installed changed the firing order, he said it didn't. He also said he did not have to reprogram the computer. On another subject, I think I am due for a new torque converter, the lockup seems to be quite loose and the slightest headwind or throttle pressure pops it out. Supposedly the E4OD tranny was replaced with one from Ford about 20,000 ago. Not sure if the TC was also replaced. Napa claims to have a stock replacement for about $320, 12 month 12000 miles warranty. I am wondering if there is a better option for me, I plow and tow but not in overdrive. I am also on a very tight budget (aren't we all). Thanks for all this valuable info I really appreciate it.