By
now most of you have probably read our two comprehensive
articles on small block Ford cylinder heads. "Heads
Up! 302 Head Buyers guide and Flowtesting" was a comparison
of the most popular stock and aftermarket heads available
at the time. "Porting
Stock Heads" was our do-it-yourself guide on porting
your stock heads. In this article we're going to discuss
the benefits of professional cylinder porting. This will
complete the spectrum of consumer cylinder head options,
as most people will either modify their stockers, bolt
on a set of aftermarket castings, or turn to an experienced
shop to get the most performance possible out of their
heads.
Head porting is as much of an art as it is a science.
Just about anyone who carefully studies and follows our
Head Porting article can see noticable gains from their
stock heads. However it takes years of practice to truly
be considered a master porter. In fact to really be a
reputable porter you not only need practice, but education
on air flow dynamics, as well as considerable experience
with a variety of heads and flow testing tools. It is
for this reason that of the masses of people who have
wielded a die grinder, only a very small few are really
master cylinder head porters. These few earn their reputation
not on the flow numbers they turn out, but on the number
of racers winning with their heads.
One such master craftsman is Brian Tooley, president of
Total Engine Airflow. The companies name alone gives precise
insight to the philosophy behind their work. As their
motto states, "It's not about flow. It's about power."
Brian has been involved with cylinder head design and
modification for most of his adult life. As a engineer
for Holley, he was a lead designer of the Holley Systemax
heads. TEA currently specializes in Trick Flow heads,
obtaining over 300cfm at half-inch lifts on just their
stage 2 porting! However Brian is quick to explain his
methodology, "The objective is to get mid-lift airflow
as big as possible. Peak flow numbers are not important."
TEA's heads crown the engines of some of the fastest Mustangs
in the country. In fact the fastest modular motor Mustang
(7.59@184mph) uses TEA ported heads! NMRA Renegade, Pure
Street, and Trophy Stock champions past and present also
turn to TEA for their head modifications.
However don't let TEA's list of heavy hitters lead you
to believe they are not accessible to the average enthusiast.
In fact just the opposite is true. TEA does the majority
of their business with guys and gals like you and I, people
that are looking to go just a little bit faster than the
competition, but are not willing to break the bank to
do so.
We contacted TEA late last year and told them about our
"Project 11.99" car, and our desires to shave a few more
tenths off the ET. Brian felt we certainly had room for
improvement with some cylinder head work. The motor had
run a best of 11.94 @ 115 with basically box-stock World
Sr. iron heads. However rather than change brands (Brian
would have preferred for us to run his Trick Flow Twisted
Wedge heads), we wanted to see what we could accomplish
with the World castings. TEA felt the 2.02" intake valve
on the World Sr. was probably too large for our 4.00"
bore, and the valve was probably shrouded. So we opted
to step down to the World Jr. casting, which has a 1.94"
intake valve and smaller 180cc (compared to 198cc) intake
runner volume. Starting off smaller would help the shrouding
issue, and allow TEA to reshape the runner for greater
flow without fear of losing air velocity into the chamber.
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 (Flow
Testing.)
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TEA reshaped the intake runners
to be a straight shot to the valve. The tapered port
creates a venturi effect, promoting better fuel atomization
and increased velocity of the charge through the runner.
Note the immaculately tear-dropped and laid back valve
guide boss.
Most small block Ford heads, stock and aftermarket,
have a restriction in the intake port due to the pushrod
hole. TEA ports through this to create the desired shape,
then sleeves it with a brass tube.
The intake port opening is matched to the Fel Pro 1262
intake gasket (1.28" x 2.10").
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TEA does not believe in overly
large exhaust ports and valves. In fact Brian generally
leans towards smaller valves, and felt even the 1.60"
valve in the World head is too large for his taste.
His reasoning is that you don't want to over-scavenge
the combustion chamber, a situation where the intake
charge is literally sucked out of the chamber during
the overlap phase of the cam cycle. Furthermore testing
shows a larger valve rarely helps. TEA aims to keep
exhaust side flow between 70-80% of intake flow.
The exhaust port opening is matched
to the Fel Pro 1415 header gasket (1.25" x 1.48").
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