I have used the search, and even brought back up a couple of old threads,but came away with not much for an answer.

I bought another 1987 Ford F150 project the other day. ( I already have a 87 4x4) This truck has a slight rod knock, but came with another engine. the engine is a 1990 model 5.0 roller motor. Will I run into any problems with installing this motor but using my factory fuel injection and computer from the truck?

 

Just swap the plug wires to the HO firing order, and it will work.

 

Thanks....anyone else want to chime in with their experiance?

 

Be sure that it is an HO motor before you swap the plug wires. It could have came out of a crown vic/grand marquis/lincoln. Those cars all had roller cams, but used the standard(non HO) firing order. Also check the back of the block (on the top right behind the intake) for a knock sensor. If it dosent have one you may need to drill and tap a hole for it.

 

Thanks for the info. I will check that out later.

The extra motor is actually a 1985 Mustang shortblock (early CFI non-roller style) but I had a friend give me a 1990 model Mustang roller shortblock.

The motor that is in the truck now is a 1986 model Mustang roller motor with E7 heads on it that started knocking when the previous owner first cranked it. He got discouraged and I got a good deal on it.

So I plan on putting the E7 heads on the 90 roller shortblock and using my factory truck computer and truck intake setup.

 

BTW, for future reference, ALL 5.0 engines made from 1988 on, used roller blocks, including trucks. They didn't all come with roller cams, but they are all able to accept roller cams. The blocks, both HO and non HO, are the same (from '88 on).

Take care,
~Chris

 

Thanks again to everyone.

Here is a pic of the old motor coming out.

 

Okay I got the motor put back in today.
I used the 90 Mustang roller shortblock with the E7 heads, factory 87 truck fuel injection and wiring. I have two computers, the 87 truck computer and a 88 5.0 Mustang auto computer.

The truck runs like crap. I have done over a dozen motor swaps and this one is pissing me off

The truck runs worse with the 87 computer, really wont even run unless you rev it up rather high.
The 88 GT computer seems to do much better, but It seems like I have a vacuum leak (power brakes are not great) and the truck will not idle unless I keep my foot on the gas. It also seems like it is skipping a slight bit.

I have another 87 truck that is a 4x4. I pulled the computer in it and put the 88 GT computer in it, seemed to run okay at first then started skipping really badly when I drove it around the block.

Any suggestions?

 

Did you remember to use the HO firing order? Definately find out where your vacume leak is.
Keep us posted.

 

did you try using the other 87 truck computer? assuming it was running correctly before. does kind of sound like an ignition problem, but it seems odd it wont idle, any chance the distributor is a tooth off?

oh yah, nice looking garage man, whats under the cover?

 

Yep tried the other 87 truck computer....same as the original 87 computer....like crap.

double and triple checked the dist. and the firing order.

Now that I have slept on it, I still think I have a vacuum leak somewhere causing my problems.
When I get home from work today I am going to remove all lines that are drawing vacuum from the motor and try to isolate the culprit.

Thanks for the compliments on my garage, I am kind of proud of it since I built it all myself.
That is my 1995 Z28 under the cover, it is a show car/ race car toy of mine. But it is mostly a Garage Queen, it hasnt left the garage since feb., I really need to sell it and put some more stuff on my Lightning!!

 

Okay.....update.

I definaltly have a vacuum leak.

the truck runs great when cold but as soon as it warms up the least bit it starts running bad, and the power brakes suck.

I found a few small leaks from rotten vacuum hoses, that got the truck running better, and I went back to the original truck computer.

So tommorrow I am going to use some WD40 and spay around to see if I can isolate the bigger vacuum leak, I hope it is something from the upper intake or above. I hope not the lower intake.

 

Check the lines going to your bypass for the smog pump.


Now then, is your Mustang ECM federal or California? There is a very big difference. If it's California, you'll be lucky to run at all, unless you have installed a MAF, but if you did, your truck ECM would make it run like crap.

 

Also, try a portable propane torch (turned on full, but not lit) instead of WD-40 to find the vacuum leak. Much cleaner!

 

Yeah, I know that 88 Cali Mustangs were MAF cars.

Thanks for the propane idea....I will try it in a little while!!