I've got a 79 with a 351 and many manuals differentiate between the W and the H model engines with regard to tune ups, etc. What's the difference between the W and the H model engines. I can't even figure out which one I have in the truck. How do you tell? Are there advantages to having one over the other? Different parts when making repairs?

Thanks for the help.

 

First off, welcome to FTE...

I've never heard of a 351H. There's a 351 windsor, 351 cleveland and 351M. Your '79 would have had a 351M from the factory - but someone could've swapped in a 351 windsor or 351 cleveland.

Count the number of valve cover bolts and notice wether the thermostat housing bolts to the block or the intake. Let us know what you find, that will tell us which 351 you have...

Marty

 

The W and H are VIN codes. you need to look at what your VIN engie code is. I do not remeber the differances off hand.

 

The H covers Both the 351M & 351W

It just depends on what year truck you are talking about.

In 1978 the H = 351M

In 1984 the H = 351W

These two engines are completely different and take 2 seconds to tell the difference.

Vans were slightly different.

If you go to the 2nd from the top sticky thread in this forum.
It will lead to a specs for both engines in 1978

 

Dont remember what the vin codes were for the 70's 351's, but once in the 80's and the 17 digit vin, ig the 8th digit was an H, you had a 351w with a 4bbl, or later ones were EFI if I recall. G codes were the 2bbl option. Do like the others say, and count the valve cover bolts, check where the outlet is for the thermostat etc, and look at the exhaust manifolds. 351m's have diagnal pattern on each port for the exhaust manifolds, where as the windsors were all inline with each other.

 

I have a 1987 F-150 4x4 351W H.O.
its a carbed 4V

 

I'm looking for the difference between a 8-351W and 8-351M (not H... stupid.... stupid... stupid). I counted 8 valve cover bolts on each valve cover and the thermostat housing bolts to the block.

The reason i'm asking is that i just purchased this vehicle a couple of months ago and the rebuilt engine has only 40k on it. tyring to figure out more as i go on...

Thanks for the help.

i can send pictures if that'd be easier. Send e-mail address.

 

No photos are necessary.

Have a look here.

http://www.oemfordparts.com/faq/smal...v8.htm#351M%20(MOUNTED)%20AND%20400

 

You can find lots of info on the 351M in the 351M/400/351 Cleveland Forum