In my ignorance, I bought a 1981 F100 on CL for $400 in the dream of using the 351W as my engine. I drove it home last Saturday and started thinking. With help on the FTE 1980-1986 forum I learned that this truck came with a 255 ci V8 (2.4L). I have never heard of that engine. This engine is a week dog of an engine in response to fuel improving demands during the late 70s-early 80s. This engine was only used a couple years then discontinued. What I thought was a 351W is actually a 255W.

I have a decision to make. Try to resell this engine and get what I initially wanted. Or, keep this engine and make it work. As a discussion piece, it is interesting and somewhat a rare piece or gem to the truck. I am just concerned that replacement parts maybe troublesome.

Opinions are very welcome and appreciated. Thanks

 

I knew they put those in the T'Birds, LTD's, maybe mustangs for a couple of years but never knew they put them in the F-100's.
I think they have a light weight crank in them that some search out for high revving builds.
Are you sure it is not a 302?

 

Are you sure it's a 255? I don't think I've ever seen a 4.2L in a truck. I've owned a few in Mustangs and a LTD.

I would not waste any money on a 255. Find a 302 or 351W. And do some research so you can tell the difference before you shell out your cash. I've been burned a few times buying things that the seller says is one thing and it's not what they say.

And the 255 is a 4.2L not a 2.4L.

 

I'm with the don't waste your money on this engine crowd.

 

If the transmission is an automatic, I would try to sell the whole truck without touching a thing. Hopefully someone is looking for a truck to use as a normal pickup.

Then you can find the engine you want.

If the transmission is a manual, then I would look into seeing if it's a TOD or similar OD stick, and keep that, and sell the rest as parts.

 

I'll add my concurrence with the others and say don't waste your time with the 255. Too many different, unique parts that don't interchange with other Windsor engines. If you want a 351, get a 351. And I also never knew Ford used that engine in trucks. Yuck.

 

52 F3-I read about the sought after light crank. I have learned that 302 (stock) intake manifold measures 7 inches and the 351w measures 9 inches. My engine measures 9 inches. The only visual clue is that the intake has the open runner (?) intake similar to the old Y blocks.

Fordman75- I am about 90% sure because the rocker arm/valve cover sticker says BK890AA (you can see the discussion on 80-86 forum under the title "VIN Help"). I am amazed how smart a person can be on the subject of Fords and the FTE users prove that time and time again.

Havi- The trans is a C4. It lost reverse so that is why I got it for $400. I am not sure what causes a trans to loose reverse but when I checked trans dip stick it was grossly high.

All- thanks for the responses. I think I will look for another donor car that has a 351w.

Good news: I bought the truck for $400. I already had a fellow FTE visit me and bought $130 worth of parts for his 82 F150. I think I can use the 9 inch because the measurement is only one inch longer than stock 53-56 measurement. With the eight wheels this may work. Finally the bench seat in this truck measures 61 at it widest. Being optimistic, this may not have been a bad deal even with the engine confusion.

Thanks again- Stephen

 

The 9" is a little too wide. But it really depends on your tire choice on the rear.

Here's my 54 when I bought it. It had a mid 80's 8.8" rear diff in it ( same width as your 9" ) .

 

Just FYI.
I believe the 80's F-100's did not have the same wheel bolt pattern as the F-150's.
It was a smaller pattern that I believe was the same as the Explorers.
That might be either good or bad depending on your plans.
Check it out.

 

The 81 F100 rear axle bolt pattern is 5 X 4.5. This is perfect because I installed an aerostar IFS that has the same configuration.

 

Yeah, Chevy did something like that too with their 267 V8. Don't waste any resources on the 255!

 

I looked in the Chilton repair manual for 1976-1986 and it does list a 255 (4.2) for 1981 and 1982, it also lists a 232 (3.8) for 1982 and 1983 can you say boat anchor.

 

Cars or trucks?

 

Sorry, Pick-ups and bronco 1976-86 repair manual.

 

Im pretty sure that scrap value of that truck is at least 1-1/2 times what you paid for it, so I dont think you did too bad on it.

Back when I was class racing I would have been interested in that 255 crankshaft. There is a very small market for them still, but typically the buyers dont want to pay much for them. In fact, I'd still buy it to put in my collection of 8.2 deck cranks. But it probably wouldnt be worth your time to remove it.