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Indy 500 Free Hourly Air Density Tuning Data: testing, qualifying, raceday

Indianapolis 500 practice: May 14-17, 2019
Indianapolis 500 qualifying: Sat May 18, Sun May 19
Indianapolis 500 practice: Mon May 20
Indy 500 Miller Lite Carb Day: Fri May 24
Indy 500 Firestone Legends Day: Sat May 25
103rd running of the Indianapolis 500 high speed circle race: Sun May 26

current imperial weather units with map & weather forecast description:
current metric weather units with map & weather forecast description:
historical weather hourly data example:
forecast weather hourly data:

Air density data for tuning to those spark plug readings, aerodynamics, & tire drift.

Air Density Online adds historic air density data

Getting Day Old and Past Air Density Data for Tuning

After numerous requests, historic air density data was added to the track listed in Now race tuners can retrieve past air density data for race tracks and courses all over the world. Here is an example of one of 23 racing facilities listed for North Carolina, USA. A screen snapshot is shown for air density / density altitude / water grains data for Coastal Plains Raceway Park in Jacksonville for March 30, 2019, approx. 11 am.

For the site selected and the current time of the viewing, air density, density altitude, water grains, and other key weather info are all displayed.  Data is accessible from mobile or stationary web devices.  Clicking on the “forecast” link (shown on the lower-left of this screen snapshot), an hourly forecast appears that is used by racers world wide for event tuning plans. 

Historical Air Density Data for Yesterday

Next to that link in the first screen shot, a new link was added, “historical”.  When that link is chosen, the previous day’s hourly air density data is shown.  A screen snapshot is shown for that list.

After a hectic day of racing, a tuner can look up weather data for the previous day with air density units already calculated.  The tuner can better reconstruct air density records for the various racing rounds for that outing.

Historical Air Density Data Going Back Further

A race tuner can enter the year, month, and day into the “Choose a date” field (shown in the right-side-center of the previous screen snapshot).  The tuner can get historic air density, density altitude, grains, and other weather data going back further than yesterday’s data.  The tuner can go back several years for hourly air density data.  To properly adjust for a new round of racing, the tuner can look at the air density from previous outings at this track with air density units already calculated.  The tuner can also look at any other track, for that matter, to retrieve air density conditions from a prior run to better select a current tune-up.  A screen snapshot is shown for an example for this same location on July 4th, 2016 if that was a previous outing.

Note: Historical data is available for most of the tracks that are listed.  However historical data is not available for certain previous dates at certain tracks.  Some of the fields may be blank or zero for missing data.  In those cases, air density & density altitude computations may be blank or zero as well.

US Race Tracks & Courses List Link:
US Race Tracks
Note: over 500 tracks listed throughout the US, most racing with mechanical fuel injection.

US Race Tracks & Courses List Subset List Links:

International Race Tracks & Courses List Link:
Worldwide Race Tracks
Note: over 100 tracks throughout the world, most racing with mechanical fuel injection.

International Race Tracks & Courses Subset List Links:

NHRA Nostalgia Drag Racing March Meet Bakersfield

Read those drag racing spark plugs for good air density tuning at the; Mar 7-10, 2019.

Check for current air density, density altitude, water grains, temperature, humidity, uncorrected barometer, wind speed, wind direction, dew point, saturation pressure, vapor pressure in imperial or metric units.

Check for yesterday’s record already determined in air density units.

Check for tomorrow’s forecast  already determined in air density units.

Check for free air density calculations determined in air density units.

Check for racing mechanical fuel injection jetting calculator.

USAC West Coast Sprint Season Feb. 27-28

Check airdensityonline weather, las vegas for yesterday, current, and forecast air density for tuning; track map; elevation; water grains; wind direction; wind speed; weather forecast; data displayed in Imperial or metric units; air density data valuable for racers without portable weather stations; for racers with portable weather stations, data valuable for re-calibration, especially after a long bumpy drive.

Autorama Sacramento 2019

The Sacramento Autorama, February 15-17, 2019 was again a hit. Our favorites were an outstanding lime green Plymouth Daytona Street Hemi appraised at well over a million, a low rider Chevy convertible with stunning modifications probable too fine to ever drive again, numerous Roots blown street rods displayed in most every one of the different halls, as well as a host of mechanical fuel injection hot rods, all our favorites. A restored Nascar 57 Chevy sedan with Rochester fuel injection, a factory cold air pack, and Nascar 6 lug wheels was displayed in the East hall together with hundreds of other custom autos and trucks just in that building. Several thousand custom vehicles throughout.  Thanks to for this special event.

We’ll be at the Sacramento Autorama, February 15-17, 2019, Sacramento Cal Expo Fairgrounds.   The Sacramento Autoorama 2018 was spectacular with a 1941 Buick show car winning the Custom D’Elegance award.  Several of my favorite Roots blown cars were throughout.  Past shows featured live entertainment, celebrity signings, and great food.  Let us know if you are showing.  We will look you up.