Hot Rods How to tell the difference between a Ford 302 or 351?

The engine and tranny are in a early 70's Econoline conversion van, I'm not hip on casting numbers or even where to look for them on Windsor engines, nor where to look them up at if found.

Thanks.

Eit:

I might add I'd like to use the engine in my '36 Ford PU, possibly the C4 as well...just want to know what I might have

 

If I remember correctly, 302 was the only V8 they put in Econoline vans until 1976.

 

Econolines had 302s also. Visually there is a quick way to tell. The deck height is 1" more on a 351, so if you look at the intake mounting surface behind the distributor, on a 302 it is not very much taller than the flat the distributor sits on, but on a 351 it is noticeably taller. The 351 intake is wider too, but I don't have measurements for any of this.

 

If it has a C4 attached to it as OEM, it's a 302. Anything larger got the C6, although you will find 302/C6 combos in all but the light-duty trucks/vans. The only 'easy' and common visual indication is that the 351 is slightly taller/wider; the 221-302 motors are about 19" wide x 21" tall, the 351 is 21" wide and 24" tall (not including the exhaust manifolds and rounded off). There's a slight difference in the shape of the oil pan rails between them, and if it's a earlier 351 count the intake manifold bolts; the 351 has 16. The 302 only has 12 bolts, but the later 351 had the four 'extra' bolts deleted so it's not always a positive identifier.

 

The firing orders are different find number 1 on the cap the wire from the first plug on the passenger side go one place counter clockwise for a 302 the wire will go to number 5 front plug drivers side a 351 will be going to number 3

 

Thanks gents, I should have it out tomorrow...good info to go by!

 

That is true to an extent. 302 HOs have the 351 firing order, both flat tappet and roller versions.

 

Just look at the distance between timing chain cover and bottom of the heads 351 is 1" taller.

 

I use a similar method to quickly eyeball the difference!
There is about an inch extra space between the distributor boss and the bottom of the manifold on a 351w [the 302 is almost flush]

 

Pics were worth a 1000 words (302 by the way).

Thanks again all!