Guys,
After a little research, I have come to the conclusion that NO holes need be
bored in the 351W heads in order to bolt them onto the 289-302 blocks. To
wit:
>From the Bay Area Sunbeam Tiger Owners Association (undated, but printed when
you could still buy a 289 HiPo shortblock from Ford)
"351 Heads
For a 'bucks up' Tiger owner, a set of 351 Windsor heads will turn you car
inside-out. With GT-40 valves, the engine will start to wail like nothing
that you've ever seen. If you're totally insane, you can have the heads
ported and polished. 351 W heads are patterned after Fords' special 'Le
Mans' heads, and they really work; the combustion chambers were designed to
eliminate spark plug 'shrouding'.
351 heads should be used on 289-302 engines only. The valves are too large
to use on a 260 engine (the cylinders would have to be 'scalloped' to accept
the valves).
Special pistons must be used to conform to the combustion chamber design.
Consult a Ford 'Muscle Parts Book' for the proper parts to use with the 351
Windsor heads. Special bolts, gaskets, valve springs, retainers, pushrods,
and guide plates must be used with the 351 heads along with the pop- up
pistons."
No mention of any extra holes in the head.....
Next the old C.A.T. parts list from the mid 70's. Parts listed are shown to
be needed to use 351 heads on the 289-302 blocks. P/N's have not been
included but if you want them, I will put them on the net.
"16 Deflector jam nuts,16 rocker arms, 16 screw in rocker studs, 2 cyl heads,
8 ex valves, 8 int valves, 8 pushrod guide plates, 16 pushrods, 8 pop up
pistons, 2 intake manifold gaskets, 20 cyl head bolts (two different
lengths).
Heads are bolt on, no mods needed"
No extra holes mentioned....
Ford Muscle Parts catalog, Chap, 3 parts id and interchangeability, under
'Heads' there is an interchangeability chart. If you go to the 351W head
column and line up with the 289-302 (4.00 Bore) line you see a big "YES"
indicating that the heads will work . There is a footnote #8 indicating the
following: "Windsor heads require minor valve train modifications and
attaching parts per pages 30-31 of Muscle Parts Book".
Those pages merely list the usual parts (pushrods, valves, springs, etc.) No
where is there any mention of any extra holes that have to be drilled into
the 351W heads.
We turn to HP Books 'How to Rebuild Your Small-Block Ford' ( thanks to one of
the listers for rerminding me of that pub).
Chap 3 , "Parts Identification and Interchange" On page 34 and 35 there is
some discussion of the different pushrod lengths, combustion chamber size,
rocker arms, etc.
Under the subsection, 'Cyl head evolution' , there is "In 1968, the last
year of 289 production, 63cc combustion chambers made the 289 heads common
with the new 302 heads" As an aside, earlier paragraphs talk about the
earlier 289 heads in terms of different comb chamber cc's, valve size,
internal plumbing for an air pump, and different types of rocker arms. The
302 heads are discussed in terms of the various combustion chamber sizes (
302 4-bbl had a 53.5 cc and the standard 302 had the 63 cc chamber), valve
types, internal plumbing for the air pump, and the hardened tips for the
exhaust valves as well as the side rail rockers. It also mentions that the
'69 heads had 58.2 cc comb. chambers.
302 and 351 heads are charactorized as 'interchangable' except for the size
of the bolt holes in the head
Under the 351 section......"Even though they are unique, 351W cylinder heads
are basically the same as all other small-block Ford heads.
Starting in 1969, combustion chamber volumn is 60.4 cc 1.84" and 1.54" valves
with .3410" stems are used. Four extra intake manifold bolts are accomodated
by a corner cast into each of the intake manifold water passages. This
changed the water passag shape from a rectangle to an L shape requiring
different intake manfold gaskets." It goes on to say that the later 302 had
the same shaped passages and in 75 the extra bolts were dropped, and the
heads were internally manifolded for the air pump. Combustion chamber volumn
increased to 69cc.
As far as I can see, there is no mention of any modification that needs to be
made to the 351W head to make it work on the 289-302 block.
I also checked my copy of 'Hotrodding Ford Small-Blocks', with no luck on the
alleged holes.
I'm not going to say that the info on boring extra coolant holes into a 351W
head to make it work on a 289-302 doesn't exist, but the sources that I've
checked make no mention of it. I tend to think that this may be one of those
urban legends.
If anyone has any concrete information on this, I'd like to hear it.
Best Regards,
Ray
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