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The signs of spring are unmistakable: flowers are
blooming, basketballs are bouncing in the playoffs, and
race car exhausts are booming. Racers are shaking off
their winter doldrums, and race cars are coming out of
hibernation in unheated garages and shops. But before
you rev up for the new season, it's essential to clean
the cobwebs out of both your brain cells and your race
car.
Racers have a tendency to focus on high-tech equipment,
but this is the time of year to pay attention to the
basics. Even the most sophisticated computers operate on
a very simple binary system: they reduce the universe to
ones and zeroes, to "Off" and "On."
A computer can tell you the driveshaft rpm at every
millisecond during a run, but it can't tell you why your
engine is popping and banging at the top of low gear.
That's something you're going to have to figure out
using your analog human brain.
Race cars are like athletes: they lose their edge when
they're inactive. They get rusty, both literally and
figuratively. There is an example sitting just outside
my office door. When Bruce Allen and I parked our
Reher-Morrison Pro Stock Firebird at the end of last
season, it had just qualified in the No. 1 spot in
Houston and |
advanced
to the semi-final round in Pomona. Ten weeks later at a
test session in Tucson, the car would hardly go down the
track!
We poured fresh gas in the fuel cell and then watched it
leak out through a seal in the fuel pump that had
hardened over the winter. When we tried to make a pass,
the engine misfired like an old lawn mower. It took a
full day's work just to get back to where we were when
we unloaded the car last November.
When an engine isn't running right, I go back to the old
"Combustion Triangle" we studied in auto shop.
The three sides of the triangle are air, fuel, and spark
- and you need all three to support combustion. If the
engine won't run, it's up to you to figure out which
element is missing.
Air supply is straightforward in a race car. Unless the
hood scoop configuration is really awful or the isolator
plate is missing, it's relatively easy to give an engine
all of the oxygen it needs. (You did remember to take
the plug out of the hood scoop opening, didn't you?)
The vast majority of engine problems are caused by the
fuel and ignition systems. These troubles can be
difficult to diagnose because |
