>Thanks for the quick reply. I've done a bit of research on the A3's
>and it turns out SVO made 3 different aluminum canted valve heads
>(non-Yates heads). The A3 has the largest ports of all the Ford
>Motorsport "high port" heads (A3, B351, C302).
Yes. However, be aware there were also additional variants. One
of my A3 sets is a "Phase 1 3/4" set which combines a narrower B351
intake port with an A3 exhaust port.
>They have pretty high flow numbers right out of the box. Here’s a
>good table assembled by Dan Jones comparing the 2V, 2V with 4V
>valves, 4V and A3 heads:
Hmmm, where have I heard that name before?
>
http://realbig.com/detomaso/1999-09/1157.html
You can also see some pictures of a few of my high port intakes and
heads at:
http://www.panteraplace.com/page35.htm
Craig's mate is right about the supply of intake manifolds for the
A3 heads. Most of the Ford Motorsport intake manifolds (Roush and
Edelbrock) were cast with C302 intake ports. The A3 intake has a
wider port. The only high port intake that I'm aware of that fits
the A3 (as cast) is the Edelbrock A331 (not to be confused with the
Roush A331). However, you can run the other high port intakes (A331,
B351, etc.) if you don't mind the port mismatch. Also, since the A3
intake port is essentially a raised floor 4V port, it shares it's
port width and roof with the 4V. That means you can use any 4V intake
if you weld or epoxy up the port floors to match. The Holley Strip
Dominator is a good candidate for this.
As far as streetability goes, the A3's might give up some low end
response to the narrower C302B's but the ports are still smaller
than a 4V Cleveland, so it's not that big of deal. They do come
alive with more cubes though. I've got a set waiting to go on a 408
cube Cleveland stroker for my Pantera. The A3's are popular among the
Pantera crowd because they share the 4V combustion chambers, valve
train, and pistons and there are off-the-shelf headers available.
Yates heads require custom everything and are several times more
expensive out the door. They also have good flow out of the box and
can be used without expensive porting. Of course, porting can up
the flow (into the 350-370 CFM range).
>I've come across a pair of SVO A3 aluminum heads setup for a solid
>roller with Manley valves (2.19 / 1.73) and K-Motion springs
Ignore the springs that are on the head and use whatever your cam calls
for.
>The only problem is the heads have been decked from the original 65 cc
>down to 50 cc, so the compression would be way up there.
The Motorsport castings are fairly thick but aluminum is less rigid
than iron so I usually pass on ones that have been milled a lot.
>Does anyone have any experience with one of these blocks? It's a windsor
>design (oiling, camshaft, distributor, etc.) with siamese bores (.030 over
>from Ford, can be bored up to .125) but has a cleveland deck height (9.2")
>and main bearing diameter (2.75"). It also has 4 bolt splayed main caps,
These blocks will often use common diameter cam bearings and require a
custom
oil pan (the pan layout is similar to a Windsor but one of the
rails does not match). When the seller calims wet sump, verify there's
a pad for the pump. Many run an external pump with wet pan. Also, the
block may have no provisions for an
oil filter (use a remote set-up).
Dan Jones