20 Winning
Engine Tips
Gems From The Pros For Increased Engine Performance
By David Miller
Racers are always looking for ways to win, but to win you must
first be competitive. Being competitive takes a lot of dedication and
attention to detail. Often a race program can lose focus on some
smaller things that add up to a better race car. This is especially
true when it comes to an engine. There are some things that can be done
to secure better engine performance without taking out a bank loan.
With this is mind, we spoke with engine builders to get some
suggestions on ways to secure more performance from an engine. Noted
motor specialists James Lyle, Eddie Labretone, and Keith Dorton
provided us with some pretty interesting suggestions on how to get
improved performance under the hood. Taken individually or as a group,
these ideas may provide new insight into a stronger engine program, and
we think they are potentially--20 ways to win.
Carburetor
1. Proper carburetor jetting has an impact on engine
performance. After an engine has been shut off, look inside the header
tube to determine the header color. This can reveal some things about
the carburetor. Charcoal-gray headers are an indication that the carb
is set up right, but powdery-white or dark-black colors may indicate
the carburetor jet is set up lean or rich, respectively. This is a
simple check that can lead to better engine output.
2. Incorrect fuel supply robs an engine of peak performance.
Running a carburetor with an angled float can help solve this problem
and regain or maintain smooth fuel flow, especially in the turns. In
the turns, standard fuel floats can restrict the fuel, while an angled
float does not. As a do-it-yourself project, this simple suggestion can
be one more building block to better engine performance.
Fuel System
3. High fuel temperature is a source of power reduction.
Insulation of the fuel line can help keep the fuel cool. Using a
heat-reflective material to wrap the fuel line is one way to keep the
fuel temperature down.
4. Heat transfer from an engine block to the fuel pump is a
source for raising gas temperature. Providing a focused air source to
the fuel pump will ease this. Fuel-pump cooling can be one of the small
things you can do to add power.
5. Don't overlook the importance of fuel delivery because
insufficient fuel volume to the carburetor can cost you power. It's
recommended that fuel lines to the fuel pump should be #10 fittings so
that a good volume of fuel is available for the pump. The exit out of
the fuel pump should be a #8 fitting, which permits the fuel pump to
keep the line constantly full.
Water
6. Although it's general knowledge that excessively hot water
temperature can rob an engine of power, it bears repeating. Hot water
can cost power. For the best performance, water temperature should be
in the range of 200-210 degrees F.
7. In the water system, severe bends in water hoses can steal
power as well. Abrupt turns in hoses can cause water pumps to work
harder, and that translates to performance loss. Water lines should
have gentle bends for the best water flow and reduction of water-pump
stress.
8. To keep water at desired temperatures, proper airflow to
the radiator is required. It's important to make sure the air-induction
shroud is completely sealed so that all the air flows through the
radiator. This is another cumulative way of getting superior engine
output.
Air
9. Keeping air to the engine cooled is an often-neglected
source of power. One way to keep air to the engine cool is to wrap air
cleaners with heat-resistant material. Doing this can keep
engine-compartment heat from elevating the engine-air source as it
passes through an air-cleaner chamber. There are some companies that
will apply coatings to air cleaners to achieve the same thing.
10. Since cooler equals free horsepower, consideration should
be given to the use of a mechanical fan to move the air out of the
engine compartment. In some applications where a mechanical fan makes
sense, this can help engine performance. This is not a blanket
suggestion that electric fans should be replaced. It is meant as a
suggestion, an alternative for moving engine heat away from the engine
compartment. Any loss in friction because of an added belt may be
offset by reduction of the load on the alternators.
Oil
11. Keeping valvesprings cool is a doorway to good engine
production. Many good oil-spray valve covers are available to help in
spring cooling. A key to making these systems work to their fullest
potential lies in the oil source. A separate oil line directly from the
oil cooler is recommended. Taking the oil out of the block before it
has gone through the oil-cooling unit is placing hot oil into a hot
environment. Keeping valvesprings cool is a means of maintaining seat
pressures. This translates into consistent power from the green to the
checkered flag.
12. The temperature range of the engine oil should be 220-230
degrees F. High oil temperatures reduce engine performance. Use of a
good radiator with an oil cooler embedded in the water tank or a good
external oil-cooling unit can help provide a solution to this potential
power bandit.
Distributor
13. Make sure the distributor is set up right. Whether the
distributor is new (right out of the box) or used, there are some
spring and weight adjustments that should be done by a reliable speed
shop that can do this kind of setup. This is a modest expense that can
deliver confidence that a distributor is at peak operating condition.
Most recommendations call for the curve advance, which should be
adjusted to 3,600-3,800 rpm.
14. When working on a distributor, any replacement of caps,
rotors, or other parts should always be from the same manufacturer as
the distributor. Often, mixed distributor parts can lead to stuck
rotors and other malfunctions. Following this rule may not be newfound
power, however, it can prevent distributor failure, which equals no
power.
15. In a 9:1 motor, running a locked distributor may be
helpful in uniform power output. By removing the springs and weights,
the plate may be locked so that it's always on full advance. With the
timing set at 38 degrees, this can provide consistent power since the
advance will not be coming in and out. Make sure you get help on this
from a qualified distributor specialist.
16. During the dog days of summer, an additional advance of
timing may be a source of better engine production. The addition of a
couple of degrees to the distributor setting might make the engine
happier and help in livening it up under the high-barometric and
high-humidity conditions of summer racing.
Electric
17. A good electric impulse to the spark plugs is important
for maximum engine power. Binding plug wires together can allow
electric impulses to cross over from one wire to another and can cause
impulse, dissipation, or interruption. A situation like this can rob
you of critical electric spark and reduce engine output. The solution
is to make sure that they are separated. There are many wire holders
available for this purpose.
18. Excessive heat can produce electric-signal interruption as
well. It's important to put thought into the routing of plug wires.
Wherever possible, they should be kept away from extremely hot surfaces
such as headers and so on. If your wires are too short to achieve
cooler routing, there are a couple of companies that make custom
lengths available to solve this problem. Any interruption of electric
impulse can steal performance from an engine. Conversely, strong and
uninterrupted signals can be a source of a powerful engine performance.
Exhaust
19. Power can be found with the right header setup. Not just
the headers, but the entire header, collector, and crossover exhaust
setup is important for engine performance. Depending on the torque
range, header configuration can be an additional ticket to higher
output. For most Saturday-night applications, good performance is seen
with the crossover pipes located 11-13 inches in back of the
collectors. As any part of the engine setup is changed, thought should
be given to a change in header setup. For example, a change in a
carburetor, camshaft, or other changes may call for a change in the
exhaust system. Consulting with a reliable engine builder of
exhaust-system combinations is a strong recommendation.
20. A rich- or lean-running engine is a source for reduction
of engine performance. A simple way to read for a rich or lean fuel
condition is by looking at the color inside a tailpipe. Using a light,
look about a foot up into the pipe. You are looking for a color that is
medium brown, which is an indication that engine fuel mixture is good.
If the color is a powdery whitish gray, it's an indication of a lean
fuel condition. A dark black color is an indication of a rich mixture.
This quick read can be done without taking the plugs out. Removal of
plugs at the track is always a potential source for introduction of
power-robbing contamination.