How do you tell the difference between a 360 and a 390 ? Looking at a 76 F-150 4x4 and the guy says its a 390. What years did the 390 come in ? Im not up on these years. Thanks for your help.

 

No way to tell them apart by looking at them. You've got to pull a spark plug and measure the stroke. 3.50" = 360; 3.78" = 390.

 

Go to the the FE engine forum. The truck would have had a 360 stock. Not a single truck was ever made with a 390 that was 4x4.

 

I was afraid of that.

 

Slug, It's not that hard, but it's most likely a 360. People call them 390s on sale day and can say "that's what I was told it was."

Grab a Sharpie, about 8" of white house wire, a socket that will fit the crank bolt, along with a helper. Pull the coil wire and ign. switch key and one of the front spark plugs. Place the wire in the hole and rest the Sharpie on the manifold touching the wire. Have the helper with a pull handle and socket rotate the engine a couple rounds and measure the length of the mark left on the wire.

Removing all 8 plugs can make the rotating easier.

John

 

The 4th digit of the VIN is the engine code.

1973/76 4WD engine choices: A = 240 I-6 (1973/74 only) / B = 300 I-6 / Y = 360 2V.

As previously mentioned, no 390 engines were ever factory installed in F100, F150 or F250 4WD's.

F100/350: 1965/67: The only V8 offered was the 352 / 360/390 introduced in 1968, used thru 1976. No 390's in 4WD's.

 

OK, thanks for the help. I told him i would let him know today if I would buy it. I think Im still going to get it for a winter rebuild project. Ill have more questions on how to get more cubes out of with junk parts later.

 

Don't lose heart. It was common practice for owners to drop in a 390 if the 360 needed major work.

I bought a used 360 just to get my truck on the road while I rebuilt the 390. Just a few weeks ago I poked around enough to determine it is in fact a 390. The PO told me it was a 360, the donor truck's VIN said it was a 360. I didn't even think to question it's being a 360. That did turn out to be a nice surprise. LOL

 

I had my 360 rebuilt into a 390. You do not have to change the bore, just the stroke to get the extra 30 cubic inches. Beware though, after you do that, you will probably want to go to a 4 bbl carb and intake manifold, then get headers, then... you are out of money! Good luck with it.

 

You have to bore the block if it's a 352, because a 352's bore is 4.00"

A 360 has the same bore as a 390 = 4.05"

 

I am curious, what was the last year the 352 was used in trucks?

 

Seems I have read if you do go to a 390 crank the bore needs to be reviewed very closely as it will most likely bet smaller at the top and snap the new sings in short order.

 

The last year for the 352 in the trucks was 1967.