Circuit Breaker
To smooth out the fuel curve across the entire
range of demands for air-and-fuel-curve delivery,
great detail must be paid to the transitions among
the three basic circuits of the carburetor. Each
circuit exists to serve its own purpose, yet all
must work together in transition to smooth out
the fuel curve, as one is crucial to the efficient
operation of the next. If any one of the circuits
fails in its task to deliver fuel, the next will
fail on its mission.
The low-speed circuit controls the idle. In the
middle is the intermediate circuit. At the very
top of the curve is the power circuit. To get a
Holley Dominator to act civilized throughout the
entire RPM band, it must be painstakingly prepared
in the same way a race engine is blueprinted in
order to hold up under the punishment of competition.
The factors that control which direction this preparation
takes depend largely on to which engine and combination
the carburetor is to be attached. Engine displacement,
converter stall, total HP and torque, and suspension
setup determine what exactly is done to influence
the operation of the circuits to make them act
naturally on raceday.
Quality, Not Quantity
As Scott Fleenor of E-Carb likes to say about
building carburetors and shaping fuel delivery, "It's
not the quantity of the fuel, it's the quality.” Scott
has been rebuilding carburetors of every sort for
almost 20 years and knows what it takes to get
a Dominator to deliver on its promises. Starting
with a bare 1050 casting from Holley, Fleenor and
his crew at E-Carb build up each part of every
system according to the custom-tailored purpose
of the carburetor. In the case of a T/S-1050 destined
for a racecar equipped with a mountain motor and
a throttle stop, great attention is paid to improving
the low-speed and intermediate throttle response,
along with improved power at WOT. A series of seemingly
minute changes adds up to serious gains in consistency
of fuel delivery, especially in the critical area
of throttle-stop "recovery.”
Beyond the workbench, every T/S-1050 is tested
and flowed on an engine before it leaves E-Carb.
Even so, Scott cautions that some minor tweaking
may be in the cards. "Obviously, my motor
is not my customer's motor, so some fine-tuning
might be required,” he said.
E-Carb supplied an impressive list of heads-up customers. Two
of the heaviest hitters, NHRA sportsman stars Steve
Williams and Mike Ferderer, confirmed increases in
both consistency and top-end horsepower after simply
installing E-Carb’s T/S-1050. Williams
added that he picked up four miles per hour, with
no other changes made to his Super Comp dragster. That’s
a level of performance that is sometimes promised
for bolt-on parts, but rarely delivered! |
