been nearly forty years since the first 289 and 302's made their
debut in Ford automobiles. Legends like Carrol Shelby immediately
went to work in search of more power out of these engines. However
back then the aftermarket availability for "bolt on" induction
parts was in its infancy. Squeezing more power out of the induction
system meant experimenting with different cam profiles, designing
and modifying intake and exhaust manifolds, and of course, porting
the stock heads. The factory 289,302,351 heads were identified
as being of poor design. The ports were small and restrictive,
even for a stock engine. The transitions from the runners to
the bowls were not conducive to smooth flow and optimum atomization
of the air/fuel mixture. Anybody that was serious about racing
their small block ford knew that the heads needed significant
port work to increase their flow capabilities. Even Ford accepted
this fact for their own race endeavors; eventually hybridizing
the solid small block bottom end with the well breathing Cleveland
heads to create the BOSS 302 and BOSS 351.
That was then. Decades of research, experience, and
of course a good economy, have created an immensely
robust aftermarket for small block Ford induction parts.
There are no less than a dozen different companies producing
twice as many varieties of small block Ford heads. No
longer is iron the only choice, but in fact it is downright
out of style. Lightweight aluminum is in, and at affordable
prices. In fact the selection is so vast that the consumer
is presented with a series of dilemmas; Which head
is right for my combination? How much can you
really gain with a home ported head? How much
better are the brand name aluminum heads?
Companies like Holley and Edelbrock have attempted to
offer a "complete solution", offering a total induction
package of heads, cam, and intakes. Seeing that 90%
of the heads on the market fall into a price range of
$1000 to $1500 per pair, it seems as if selecting a
cylinder head for your 302 is a can't lose proposition.
The fact is that there is quite a bit of difference
in the offerings, and getting the right head for your
combination ultimately means getting the most horsepower
for your hard earneddollar. The question of which head
to go with has plagued us at FORDMUSCLE for quite some
time. In fact we simply grew tired of all the conflicting
data presented in the magazines, on the web, and even
on TV. Depending on who is paying the bills that month,
their head seemed to be the best flowing, or the head
of choice for all 302's. We got frustrated with that
line of approach, and decided it was time to do our
own independent "study". Don't get us wrong, we aren't
saying that everything we've ever read or seen is a
lie or embellishment. We simply don't know what to believe,
so we wanted to get results for ourselves, and offer
them as a collective, independent source of information.
goal was to provide you the reader with an independent
source of information that you could use to make your
head selection decision. Of course we needed an objective
way to compare the heads. That is where the flow bench
comes in. But we should make some disclaimers. Simply
looking at flowbench numbers doesn't mean much of anything.
Like a dyno or any other piece of test equipment, there
are margins of error and confidence levels. Comparing
flow numbers from manufacturer to those from another
is not a sound comparison, since the heads were not
tested at the same time, by the same operator, on the
same machine, etc. That is why we wanted to get all
the heads under one roof and test them under the same
conditions. This way you can be assured the differences
in flow numbers between the heads is accurate and reliable.
However don't expect to see our numbers to be dead on
with what the manufacturer's catalogs state.
The point of this article isn't to simply find the highest
flowing head and proclaim a "winner". Rather,
the point is to compare and contrast the different heads,
and compile a buyers guide that will assist you- the
consumer -in your selection. The bottom line is that
every head in our test has seen varying levels of success..and
failure, so it would be foolish for us to say Brand
A is the best head, since on the wrong engine the results
could be terrible.
Getting the Heads
The first step was to obtain and flow test virtually
every small block Ford head on the market. If it sounds
like a tough task, trust us... it was. So much so that
several times we contemplated canceling the project.
The hardest part was to obtain all the heads. We contacted
every major manufacturer and invited them to participate
by loaning us an off the shelf head. We would test it,
photograph it, and return it when we were finished.
The manufacturers of course would receive product exposure
via this article in exchange. Keep in mind none of the
manufacturers paid us to include their head. Furthermore
none of the manufacturers pay for advertising on this
site. In the end we ended up a large selection of heads,
covering the majority of the market, however we did
not get every head out there. We excluded the really
exotic stuff, like the Brodix Neal, and Edelbrock Victor.
Anyone really in the market for a head of that caliber
is beyond the knowledge presented in this article! This
article focuses primarily on heads which are offered
complete, and can be bolted on a 289, 302, or 351 without
Needless to say some companies declined to participate,
others only sent one model eventhough they offer several,
and some still tell us they are planning to send us
heads...some eight months after we first contacted them...
uh huh, right. Nevertheless, we did get a critical mass
to do our study. One important lesson learned here was
regarding customer service. The companies that immediately
followed up with our invitation, whether it was to participate
or decline, gave us the impression that they would be
good to deal with if you had any problems or tech needs
after purchasing their products. On the other hand the
manufacturers that kept yanking our chain, breaking
promises, and holding up our schedule, in our opinion
may do the same when you have a problem with their product.
Air Flow Research (AFR) did not submit either of their
two highly touted 5.0 heads. Ironically, this whole
project idea was kicked off back in September 1999 when
we met AFR at the SEMA show. At the time they had been
promising their new 5.0 heads to the public for nearly
a year. They promised to deliver us heads for the article
by Thanksgiving of that year. To make a long story short,
we waited and waited, but they never came through and
thus the delay in getting this article to you the readers.
Canfield respectfully declined, stating that they no
longer have any desire to work with the media, because
they recently had been burned by a magazine article
that printed a competitors flow numbers even though
the editor of that magazine knew the heads had been
modified. Whatever, we tried. Of course we could have
spent our own money and bought the heads we didn't get,
but again we don't have the budget, and we aren't about
to get stuck with heads we don't need.