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Someone might be able to answer this

2K views 15 replies 8 participants last post by  max_torque 
#1 ·
#2 ·
re

As far as I know you can't tell a 351 clevland apart from 302 because they have the same block but use different crank, rods, pistons & the 302's have small chamber heads. As for the windsors the 302 windsor has a deck height of 8.206 in & 351 windsor has deck heighet of 9.506 in. This makes the 351 wider and taller then the 302 windsor. The only way to tell the difference between the two is to measure the stroke. You have to pull one of the sparkplugs out (usualy number one) & turn the engine over by hand until the piston goes all the way up the bore & when you feel that it's trying to go down you stop & stick a piece of straight wire in the hole. You make sure that the piston is all the way up. You mark the spot on the wire & then you turn the engine over by hand and let the piston go all the way down untill you fill that the piston wants to go up again. You mark that on the wire as well & then you just mesure the difference between the two marks. This will roughly tell you how big is the stroke of the engine. The 351 should be 3.5 inches & the 302 should be 3 inches. The difference between the clevlands & windsors is the thermostat housing is bolted on the manifold on the Windsors & on the clevlands its bolted to the block. Clevlands have a cast iron factory intake manifold & windsors have an aloy factory intake manifold. I hope that helps.
 
#4 ·
Mate..... For a seriously impressive read.... Go see if you can still buy "Street Machine Workshop Series #2" It was published in 1989 & has all the info a Revhead could ever want on tough 302's & 351's. Cleve's & Windsors..... I keep mine locked away with afew other goodies :eek:p
 
#5 ·
The blocks are different, the cleveland has a longer block. It has an extra lip out the front for the water pump. Also the head ends up flush with the front of the block on a windsor while the clevelands extra long block hangs forward just over an inch. The rockers are massively different in that the cleveland has big rockers that are canted (splayed) while the windsors rockers are all in line and a lot smaller.
 
#6 ·
Dreders said:
The blocks are different, the cleveland has a longer block. It has an extra lip out the front for the water pump. Also the head ends up flush with the front of the block on a windsor while the clevelands extra long block hangs forward just over an inch. The rockers are massively different in that the cleveland has big rockers that are canted (splayed) while the windsors rockers are all in line and a lot smaller.
that's all good but he want's to know how he can tell it apart without pulling it apart
 
#7 ·
The longer block is pretty obvious, if there is a 1 inch chunk of cast iron block behind the water pump then its a cleveland. You dont have to remove anything or even be that close to the motor to see that. If I had a scanner I could show you what I mean but you dont have to remove anything.
Removing the valve covers is the best for absolute rookies but it isnt even fool proof because some people put cleveland heads on windsor blocks.
 
#10 ·
Generally speaking the early australian clevo 302's were released with orange/redish painted valve colours, & the 351's were painted blue.
This is by no means conclusive as it is quite simple to change the colour of valve covers, or even the type of cover fitted.
only conclusive way is to check stroke length, either by measuring through sprkplug hole,or removing head(s), or removing sump.(not forgeting overboring etc)
 
G
#11 ·
Wulos> overboring??? how does this impact on stroke??? The bores on 302s and 351s are std 3" - only the strokes are changed to achieve the extra swept displacement.

Trivia Q. Did you know that the 351 isn't really a 351 at all? It is in fact 352 cu in displacement but Ford didn't want to cause confusion between the old "Y" Block 352 so they called it "351"
 
#12 ·
Cobra188 said:
Wulos> overboring??? how does this impact on stroke??? The bores on 302s and 351s are std 3" - only the strokes are changed to achieve the extra swept displacement.


Ahh 4 inch bore on both mills matey!!!
 
#14 ·
I was thinking of factors that effect dislacement at the time.ie difference between 302 & 351......(not just about the more common crank swap)
Therefore I felt it necessary to mention overboring as well.
 
#15 ·
re

Now a 351 Windsor is really a slightly enlarged 289/302, as it's name implies it comes from Fords "Windsor" engine family (a.k.a. the 90-degree V engine family). The thin-wall cast SMALL BLOCK accepts regular sized spark plugs, uses a timing chain in the block, routes water through the intake manifold, features thin main-bearing caps, a very good oiling system, and uses the same heads for 2V & 4V versions. The heads are are small, utilizing in-line valves with relatively small ports. The valves are 1.78" intake and 1.54" exhaust, i.e. the same size as a 289/302. The valve covers are straight (front to rear), attached by 5 bolts, and when removed you can see 351 cast in the lifter valley. The small side-by side (in-line) valves are the dead give-away.

The 351 Cleveland, on the other hand, belongs to Ford's 335 engine family. This thin-wall cast BIG SMALL BLOCK uses the smaller 14mm spark plugs, has a separate front cover (bolted to the block) housing the timing chain and routing water - so that water does not go through the intake manifold, features beefy main caps (wide enough to drill for 4-bolt mains), a poor oiling system, and uses different heads for 2V & 4V versions. The heads make all the difference and these fire breathing babies make this motor the legend it is. On the 4V, the valves are HUGE, measuring 2.19" intake and 1.7n" exhaust (don't remember exactly). Valves this large are only possible via a canted valve arrangement, forming what Ford refers to as a "poly-angle" combustion chamber. The valve covers are not straight - the front is flat and parallel to the ground, but a curve twists the rear parallel to the head. They are attached by 8-bolts and when removed, there is a 4 cast into the corner of the 4V and a 2 cast into the corner of the 2V (at least in 1970). The canted valves are the dead giveaway.
 
#16 ·
clevo IDs

There is also a later 'black block' evolution of the cleveland. This has thicker walls, and smaller distributor bush size for electronic distributor. You can tell these externally because shield shaped bosses are cast into the outside wall just below the head surface.

If you have the cam out of a cleveland you can see in where the crank has the number cast.
 
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