5.0 HO Engine in to 91 f-150
 

Does anybody know what extra work will be involved in putting a 91 5.0 H.O. thunderbird engine in to a 91 f-150? I currently have the Edelbrock shorty headers. Will they bolt back up? Will the computers be the same? Will my clutch still work? Oil pan? Am I missing something else? Thanks in advance for the help.

Sorry.... Forgot to say I cuttently have a 5.0 in it with 222,000 miles.

Everything will swap over to the HO , main difference is the roller cam , headers will work fine , so will the truck computer and oil pan and intake and accessories , if you use the truck distributor it will need a steel gear on it , you will need to use the HO firing order....Lew

All 5.0 motors are built using the same basic components(block and heads) so if you strip the car engine down to the bare longblock all the truck specific parts will bolt right on. Those parts include the oilpan and pickup, complete intake and fuel rail, timing cover and water pump, accessory brackets, and the distributor if necessary. Note that if your truck has a distributor with the TFI module mounted on it then you can use the car distributor which is setup the same, and you want to use the car dizzy because it has a steel drive gear for the roller cam in that motor. If however your truck has a fender mounted TFI module you will have to pull the steel gear off the car distributor and press it on your truck dizzy.

With all that done the motor will bolt right in place of the old one using the existing flywheel or flexplate, and connect to the stock truck wiring harness, the only change necessary is to route the spark plug wires for the HO firing order. You can expect the motor to be a little softer at low rpms but it will have more midrange and top end power.

Thanks for the info. I was curious about the firing order. It seems like everything else will work. I do have the ignition unit on the dizzy. So it sounds like all I will have to worry about is the firing order. Thanks again. Your answer was very helpful. My main concern was the computer, but it sounds like that will work. My current motor now has a map sensor, not mass air. I am not sure what that other motor has yet.

It doesn't matter what EFI system the other vehicle has, it has no impact on engine compatability with your truck.

Ok. One more question. What about the injector firing order. Do I put the wires in the same place as the non h.o. motor and only change the spark plug wires? Or does all that stay the same? I pick the motor up tonight. I should start stuffing it in tomorrow. I will follow up with how it went. Once again I appreciate all the help.

On the 91 the injectors are batch fired so leave them the same , just change the plug wires to the HO -351 order....

the 91 5.0 truck is a roller motor so the truck dizzy will work . like the others said swap the needed accessories , and pan.

Ok. Just an update. Got the old motor tore down and the new motor prepped and sitting in the truck now. Nothing is hooked up yet ( I should have it running tonight). The old motor was not a roller motor, I thought it was. Had to extract the front 2 intake manifold bolts on the new motor. common problem from what I hear. The inside of the new motor looks great. The old motor had a hole thru #8 piston. Commom problem from what I hear because of the pcv. I have already done the switch moving the pcv to the vaccum tree. Also the inside of the old motor looked like someone poured 10 gallons of stp in at every oil change every 30,000 miles. Worst motor I have ever seen. Thanks for all the help. I will update tomorrow if I get it running tonight.
:-drink

you need to get a dizzy out of a 92-95 truck then for it

Not necessarally, worst case he may need to remove the steel drive gear from the car distributor and press it on the old truck distributor, but if both motors had distributor mounted TFI modules then he can use the car dizzy as it is.

Actualy the one I pulled out of my truck had a steel gear. I plan on re-using that.

awsome! conanski, i agree to, but getting the gears off in 1 peice isnt always easy!

Sure it is. Take it to a machine shop and have them press off the old gear and press on the new one. takes 10 minutes.