There were two different A351 intakes, one was for for high port
(A3/B351/C302 heads) and one was for Yates heads. Both were for
9.5" (Windsor) deck blocks. However, it's common to machine them
for 9.2" (Cleveland deck blocks) in which case it's really a B351.
A351 (9.2") and B351 (9.5") intakes share the same casting, as do
C351 (9.5") and D351 (9.2"). The A331, A351, and B351 do not have
waternecks while the C351 and D351 do have waternecks. The high
port intakes will bolt up to 4V heads but there will be a port
mismatch. The best match is the Edelbrock A331 which has a 4V
width. The rest of the high port intakes (including the Roush
A331) have narrower ports. All have raised floors. The roof is
generally close but may require a bit of port matching. Sometimes
there will be a flange mismatch (gap) at the port floor. A Roush
port stuffer should fix that.
Be aware that most of the Yates intakes were designed for restrictor
plates and may not work as well as the high ports in unrestricted
applications. Also some are 2 piece designs, requiring a valley
cover. Some (the E351 for one) are very heavy since they were
designed with maximum material for porting.
I've got a small collection of high port intakes. If I get the
chance, I'll do a fit check this weekend to see how they match 4V
Ford re-used part numbers and changes the listings in the SVO/FRPP
catalog from year to year just to make things confusing. The
formatting may not make it thorough but here's my latest abridged
list of high port and Yates intake:
Intake Manifold List for Yates and SVO High Port Aluminum Heads
Part Number Deck Head A/B Description
M-9424-A331 9.2 A3 4.90/5.90 Similar to an Edelbrock Torker
casting with the lower port sections
filled in to match high port cylinder
ports, no air gap, no carb heat
M-9424-A331 9.2 A3/C302 6.25/6.25 NASCAR single plane, Roush
M-9424-A351 9.5 A3/C302 6.50/6.50 NASCAR single plane, Roush
M-9424-A351 9.5 Yates 6.50/6.50 NASCAR single plane, C3L flange
M-9424-A351 9.2 Yates 6.50/6.50 NASCAR single plane, C3L flange
M-9424-B302 8.2 Yates 7.00/7.00 C3L on 302 block, 2002 catalog shows
7.75 inch height
M-9424-B351 9.2 C302 6.30/6.30 NASCAR single plane, short track
M-9424-C351 9.5 C302 7.36/7.36 single plane Edelbrock, waterneck
M-9424-D351 9.2 A3/C302 6.94/6.94 NASCAR single plane, Edelbrock,
M-9424-E351 9.2 A3/C302 6.40/6.40 NASCAR restrictor plate
M-9424-E351 9.2 Yates 6.40/6.40 NASCAR single plane, restrictor,
C3L, heavy, thick walls for porting
M-9424-EE351 9.2 Yates 7.50/7.50 single plane, restrictor plate,
lightweight, no valley tray, 2002
catalog shows 7 inch height
M-9424-F351 9.5 A3/C302 6.60/6.60 NASCAR single plane, restrictor
M-9424-F351 9.5 Yates 6.60/6.60 NASCAR single plane, restrictor
M-9424-G351 9.2 2V iron 3.50/4.30 street dual plane, Edelbrock
M-9424-K351 all C302 ---/--- Kinsler fuel injection
M-9424-L351 all B351 ---/--- Kinsler fuel injection
M-9424-M351 all A3 ---/--- Kinsler fuel injection
M-9424-N351 9.5 A3/C302 ---/--- NASCAR, 2 piece for use with
M-9424-S352 9.2 Yates 6.75/6.75 NASCAR single plane, C3H, 19.5 lbs,
thick walls, tuned for high speed
tracks, 4 inch deep plenum, no valley
tray, can be modified for use with SC1
heads (slot hold down bolts)
M-9424-W351 9.2 Yates 6.87/6.87 NASCAR single plane, 4500-8500 RPM
M-9424-W351 9.2 Yates 7.97/7.97 single plane, no valley tray, C3L,
M-9425-W351 9.5 Yates 7.50/7.50 single plane, C3L, short track, no
M-9425-W351 9.5 Yates 7.00/7.00 short track, C3L flange, no
valley cover, 2002 catalog
M-9424-W352 9.2 Yates 7.50/7.50 short track, C3H flange, no valley
M-9424-X351 9.2 Yates 7.00/7.00 NASCAR single plane, C3/C3L, 19 lbs,
4 inch plenum depth, tuned for power
increase above 8500 RPM, no valley
tray, replaces M-9424-W351
M-9424-Y351 9.5 Yates 6.87/6.87 NASCAR single plane, 4500-8500
Edel #2932 9.2 SC1 8.38/8.38 single plane, 3.2 sq. in. runners
Edel #2933 9.2 SC1 8.27/8.27 single plane, 3.0 sq. in. runners,
Edel #2960 9.2 Yates 6.97/6.97 Victor GN 351-Y, NASCAR Busch,
Super Truck, and Winston Cup, no
Waterneck, 2.8 sq. in. runners
Edel #2961 9.2 Yates 6.97/6.97 Victor 351-Y Spider, NASCAR Busch,
Super Truck, Winston Cup, 5000-8500
RPM, no valley cover, 3.2 sq. in.
runners, no waterneck
Edel #2987 9.2 A3/C302 7.36/7.36 Victor 351-AH
Edel #2990 9.2 A3/C302 6.81/6.81 Victor 351-AH II 4500-8500, has
Edel #2991 9.2 Yates 6.97/6.97 Victor 351-Y 4500-8500 no waterneck,
2.95 sq. in. runners
IA-104BP 9.2 A3/C302 ---/--- Inglese downdraft Weber intake,
4 x 48 IDA
1. In the above list, A3/C302 refers to the entire range of high port,
non-Yates, heads - A3, B351, C302, C302B, D302, and D302B. The
Yates intakes cover all except the recent "high port" version of
the Yates heads.
2. Note there are two A331 intakes for the 9.2" deck height block.
One is a Roush intake and has "Jack Roush Eng" cast into one
of the intake runners and the A331 part number cast into another.
It has a level carb base (A/B heights equal) and is an air gap
intake like most of the other SVO high port intakes. The other
is basically an Edelbrock Torker with the lower portion of the
ports filled in. It has the A331 part number and Ford Motorsport
cast into the valley cover part of the intake and a canted carb
base. I have never seen any mention of the Edelbrock A331 in any
of the Motorsport literature.
3. The Kinsler manifold includes magnesium two piece castings (each
bank of four injectors bolts independently to a head), 2 7/16"
diameter throttle plates, stainless steel throttle shafts with
bronze bushings. Since they are two piece manifolds, bolting
directly each cylinder head, they will fit any deck height block.
Originally, SVO also listed three separate part numbers for the
Kinsler mechanical injection manifolds. Part number M-9424-K351
was for C302 heads, M-9424-L351 for B351's, and M-9424-M351 was
for A3's. In later years, only one part number, M-9424-K351 was
listed for the Kinsler injection.
4. It is rumored that when SVO introduced the Yates heads, there was
a screw up with the part numbers for the intakes, assigning the same
numbers to both the standard high port intakes and the Yates intakes.
If you look at the table of intake manifolds above, you'll see
several part numbers that are shared by both the A3/B351/C302 and
Yates compatible intakes. I've been told that SVO's response was to
destroy the remaining non-Yates intake. Whether or not that is true,
it is true that intakes for the A3/B351/C302 heads are rarer than the
cylinder heads. Also, many of the intakes on the used market have
been ported, typically to increase high rpm power. If you're looking
to run one of these on the street, try to find one that's not been
ported or only lightly ported.
5. Now that Brodix has introduced a C302B replacement head, there's a
rumor that a second party may reintroduce the A351 and B351 SVO
high port intakes.
6. Intakes meant for standard Cleveland heads can be used with SVO high
port heads, though the extent of re-work necessary will vary with the
individual port size. The A3 intake ports are *not* relocated upward.
They simply have the lower portion filled in so any 4V intake will
bolt up. All that's required is to fill the lower part of the port
with aluminum weld and port match. I noticed this would be particularly
easy to do on my Offy 360. The port opens up (more precisely drops down)
at the end of the runner. Only a short section of the runner would
need to be welded up to match. B351 and C302 heads have smaller ports
so may require additional welding and/or port matching.