Hey I got a 86 f150 xlt lariat. Its got the old 5.0 in it now it's 2 wheel drive. My motor is about shot I'm really debating on rebuilding what I got or put something bigger I was thinking about the 5.4 Triton v8 cuz of the pulling power.the truck is going to be a work / play truck it's going to c a lot of trailers and heavy *** loads for example I pulled a 25ft pull behind camper idk how much it ways I just know it's heavy.idk what motor really to get but I need advice on the matter please give advice nice or not I need all I can get

 

Welcome to the site, and your first post..

With the year truck you have, I'd stay away from the Tritons.. Sure, you can put anything into anything with enough time and money, but that would be a lot of work.

I'd stick with an engine from that era, but your only choices are going to be the 351 or the 460.

460's didn't come in the F150's, but I'd bet it would fit...

351's were put in them, but you'd want to add some parts to it to bring out some of it's power potential. I towed heavy with one in an E250 van when it was brand new (1988) and it was pedal to the floor, 1st gear, 25 mph up any grade... But, it did it without issue!

You could just rebuild the 302, but they are not known for their low end grunt, which is what you want for towing..

Or, just take the money you'd spend on this project and put it towards getting a used 97-03 F150... They might have some miles on them, but if they've been maintained, they will go a long way.. I traded my 97 F150 with the 5.4 in it on my 13 and it had 255,000 miles on it and going strong.. They didn't give me much for it, and I was sad to let it go that way, but that's what I did and someone out there got a damn nice truck for probably less than $6000...

Good luck!

Mitch

 

Yea but also take in mind that I'm also having to replace wording harness so that would really be a problem I'm also replacing front end well really and truly I'm redun pretty much from the Hood down

 

I owned a 1986 F150 Lariat SWB 302, C6 trans, 3.08 rear truck for a while. And i towed a 25' TT from Raleigh NC to Disney World. It did just fine on flat land. Turns out that at 65 mph the engine was at its torque peak which was perfect. Ford recommended a 3.55 or lower rear for towing.

I suggest you rebuild the 302 if you keep it and change the rear gear for towing. That is, if you keep it. The best solution would be to get a newer truck. When I traded my 94 XLT F150 302 SWB 4x4 for a new 2000 F150 XLT 5.4 Scab 4x4 I found the newer truck to be better on gas and had quite a bit more hp/torque also. The real reason I traded was that the 94 was noisy on the interstate where it stayed most of the time and the front tires cupped out no matter how well they were balanced due to the sort of dual Ibeam axle. I was very pleased with the 2000 and the 2002 I have now.

 

The 302 is a great engine and will/can perform every bit of the 5.0

 

The 351/5.8 has more torque than the 302/5.0 and is a better engine for towing and hauling heavy loads. That's why you won't see a 302 in a F-350, the 351 was the standard V8. It's also a fairly easy swap.

 

The 351 went to fuel injection in 88. So your 86 would be okay with a carb as far as the inspection is concerned if that is an issue. It will burn a lot more gas than the newer 5.4 engines. The 302 burns a lot more gas than the newer 5.4 with OD.

 

Here's how I see it. If you are just going to keep the truck with stock size tires, rebuild your engine, a mild cam, and put a 3.73 axle or maybe even a 4.10 axle in it. If you think you are going to jack it up and put 37" tires on it, go big block or forget it. The little engines just don't have the grunt necessary. You can find the old 429s and 460s in junk yards dirt cheap these days. They can be carbed or fuel injected. You can get the harness and PCM out of an F250 and it will work fine. Frankly, if you're going big tires, just find an old F250 with the 460 engine. There's a bunch of them out there with low miles as a lot of folks used them for trailer pulling but didn't like the fuel mileage so they got parked a lot.
FWIW, I had an 86 XLT Supercab with the 302 and 3.55 gears. While I liked the truck, it was no trailer puller. It just about run out of power with a 3500 lb trailer and that's with stock tires. Nice truck but the engine was no powerhouse even with the "new at the time" fuel injection. Mine had the AOD transmission. It was not a good long life transmission so consider a rebuild on the transmission in your budget.