I've touched on this question before within other threads, but not totally nailed it down. I will post some pictures later today, but in the meantime, how do I determine if my engine is indeed a 351W or something else? I know one of the identifying features of a 351W is the 45ish degree radiator hose connection that goes into the intake manifold, but my engine has an Offenhauser intake manifold (that much I know for sure as it says Offenhauser right on top of it, just in front of the carb). So the radiator hose connects straight to that. It IS at a 45 degree angle or so, but still, it seems ambiguous to me because of the aftermarket intake. What else can I look at to remove all doubt?

It sounds pretty cool, if that helps.

Thanks! It's tough being a newbie and inexperienced. I have a few questions that are so embarrassing I won't even post them!

t

 

If the heads haven't been replaced you may be able to take the valve cover off and i'll be stamped in the heads. I know they were stamped in my 302.

 

hard to see, but the block number is stamped above where the starter is.

mine looks like this, notice the bottom of the block is at the top (where the oil pan connects)
this is a 1994 351w block that supports a roller lifter camshaft

sam

 

Quoting the master guide:
Frequently Asked Questions (FAQs) on Adapting Major Components of 1948 to 1960 Ford Trucks .: Articles

Q. How do I tell the difference between a 302, a 351W, a 351C, and a 351M?
A. By using combinations of the following facts, you should be able to positively identify what engine you have.

• The number of valve cover bolts per head

o FE = 5
o 351W = 6
o 351C = 8
o 351M = 8
o 335 series big blocks = 7

• The thermostat housing location

o 351W has it on the intake manifold
o 351C has it on the block

• Fuel pump mounting style

o 351W has bolts on each side of the fuel pump
o 351C has bolts on the top and bottom of the fuel pump

• Water pump boss

o 302 water pump boss goes right up to the bottom of the head
o 351W water pump boss stops below the top of the block " about 1” below the bottom of the head

• Firing order

o 302 firing order is 1-5-4-2-6-3-7-8
o 351W and late 302 H.O. firing order is 1-3-7-2-6-5-4-8

• Dipstick location

o 351C has the dipstick going into the block
o 351M has the dipstick going into the oil pan

• 351W eighth digit in the engine ID number is generally an “H”

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I'm more of a 302 guy, so have not owned a ton of these (only a W, never owned a C)... so I will leave it at that and let the experts give you any more info.

 

Here's a couple of the features that Brain75 mentioned:

Here's a 351 Cleveland....it has a straight up water outlet off the block and the dipstick in the front:



Here's a 351W with the intake manifold mounted water outlet, and you can see the distance between the water pump mounting boss and the top surface of the block (the head gasket line):



They all sound cool....so that's not a good way to determine which engine you have!

Dan

 

Tyler,
You can ask whatever questions you have. You might get some good natured ribbing but that's about it & your question will be answered.
If you post a pic of your engine I'm sure you will get the engine ID'd quickly.

Ben in Austin

 

I've barked at one guy here (and I probably shouldn't have) for "answer shopping" - asking the same question 6 times hoping to get the answer *he wanted* as opposed to the correct answer or a way to figure out the answer for himself... For the most part Ben is dead on - not many people here bark... The folks who bark aren't really welcome as we are a bunch of friendly guys hanging out in the shop.

(I deal with ignorant managers who answer shop at work, so I am a bit easily peeved by it.) But I do follow the philosophy here to be just a normal friendly guy and ask/answer as things come up. Everyone has good and bad days, and you have to let some things roll off your back occasionally .

You were really considering a rear end swap if I remember right. And I see you opened a mushy brake thread - did you swap, replace pinion, or?

 

Another way of determining between 351w and 302w (they did make a Boss 302 which uses cleveland style heads, but we won't go there to keep it simple) is the block width. The 302 is about 5 " across where the front intake gasket sits and the 351 is about 7". This is because the deck height is higher on a 351.

Between a 351W and a 351C (with stock heads) the spark plugs on a W take a 13/16" socket and a C uses a 5/8" socket.

Hope these help a little.

 

That's not a good rule to rely on. Ford did in fact use the larger plugs with a 13/16" hex on all the Windsor family small blocks - but only until about 1978. After that, they ran the same 5/8" hex plug that the old 351C used until the end of production in 2001.

 

When I bought the oil pan for my 351W, I "THINK" it was a different width than the 302 pan. 351W is wider, i think.. I have my old oil pan still and could measure the width or number of bolt holes real easy, but will that even help?
I know we gotta know for sure rather than just guess.
Also a dead giveaway should be the width of the intake manifold. they are not interchangeable 351W is wider. Okay some of you guys may not remember this, but TYLER posted pics of his engine in the beginning and if I remember correctly it was narrowed down to either a 302 or a 351W. I am going out to measure from inside of valve cover to inside of valve cover. Will be right back...

 

ok my 351W measures, from inside edge to inside edge of the valve cover, like right down where the gasket would be, 11 3/8 " thats real close.
Some one out the got a 302 with valve covers on? that can take a quick measurement?
I looked on Summit racing, and they list manifolds for the 260-289-302 and a different manifold for the 351W, so maybe this will get resolved for ya real soon!

 

I didn't catch this one at first, but I also checked my 351W and it is about 7"
where indicated above, but with the engine assembled, it's a bit difficult to get down low enough to really tell for sure. I don't have my front clip on so it wasn't too bad to do.
So agreeing with truckeemtnfords, the two engines have different width intake manifolds. this should help ya out! let us know!

 

Tyler the only stupid question is the one not asked. So never be embarresd to ask. I see your already a supporter, rite on and good luck with your progect.

 

If using other info from this thread, you've decided you have a "Windsor" small block...

The easiest way to determine whether it is a 302 or 351 is to look next to the distributor hold down bolt & if there is a 45* support rib cast into the block, it is a 351. No support rib, 302.

 

Hey Tyler,
Have you reached a conclusion on what type of engine you have?
We are like Paul Harvey - we need to hear "the rest of the story"....
I think the water pump outlets are the easiest clue to what you have -
351W has a very distinctive look.

Ben in Austin