Daktronics C44 - Manual (Page 32)

3-4 C-44 Race Timer
Operation
Altitude Adjustment
An Introduction to Altitude Adjustment
Many race car engines run better, and consequently the cars move faster, when the
air available to the engine is denser. In general, cars will run faster at sea-level
tracks than at high elevation tracks such as in “mile high” Denver. The drag racing
industry has developed lists of altitude correction factors that can be used to adjust
E.T. and MPH values for races that are run at various altitudes. The basic concept is
to adjust the E.T. and MPH values that are experienced at the higher elevation tracks
to sea-level values so that all results can be directly compared.
In the past, the E.T. and MPH values had to be manually adjusted using the altitude
correction factor when preparing a timer for a race or verifying the results. The
altitude adjustment feature of the C-44 timer allows this operation to be performed
automatically by the timer to prevent errors and allow quicker verification of race
results. The C-44 also allows the automatic altitude adjustment function to be
quickly switched off if manual calculations are desired or if the altitude correction
factors are not used for some races.
The C-44 system allows three sets of adjustment factors to be entered by the
operator. Each set contains one factor for adjusting the E.T. and one factor for
adjusting the MPH. This allows different categories of classes to have different
adjustment factors pre-entered and quickly available for each race. The
determination and accuracy of the actual factors used are the responsibility of the
track operator and the track’s sanctioning body.
Altitude Adjustment Example
Figure 2 shows the results of a race that was run using the altitude adjustment factors
of the C-44.
1. Notice at the bottom of the screen: Altitude adjustment feature is turned on
("ADJ"). Adjustment factor set #1 is selected. This factor set has an E.T. factor
= 1.0000 and speed factor = 1.0000.
2. Dial-ins were entered as sea-level dial-ins. Dial-ins of 10.25 for the left lane and
10.17 for the right lane were entered.
3. The C-44 automatically divides the sea-level dial-in by the E.T. adjustment
factor to produce an actual (at altitude) elapsed time value that will be used to
Figure 2: Altitude Adjustment Example