Air Density Online

weather calculations for racing engine tuning


Jet your car from anywhere with an internet connection. Have a smartphone? You now have a portable jetting calculator.

for tracks

Real-time density altitude from current weather data at various tracks including: NHRA & IHRA dragstrips, road courses, dirt ovals.


Get your MFI fuel system setup programmed into ProCalc. Even get your dyno data added. You get 1 year of access to ProCalc too!

Thanks for visiting our site. We provide real-time, historical, and forecast weather data for racing engine tuning. We also provide engine tuning tools for mechancial fuel injected racing engines. We are constantly adding tracks to the site. If you'd like to see your track added to the list, send it over. Learn more about this site and it's creators or read some of the articles we've written.

What's New

June 9, 2022

More on the High Speed Bypass for MFI from Brad Cauzillo, Kinsler FI

high speed bypass from an Outlaw Sprint Car

In our recent MFI high speed bypass article, a photo is included showing a high speed bypass from an Outlaw Sprint Car running at the Placerville Raceway, Placerville, Ca:

Brad Cauzillo, Marketing Manager, Kinsler Fuel Injection, added the following info to that photo: " NOT to plumb your race car.

The bypass valves should:

  • a) Be plumbed as close to the pressure change source(barrel valve) as possible
  • b) Never rely on a aluminum union fitting as a mounting source.
  • c) Be connected with a length of hose on the inlet and outlet to provide anti-vibration for the internal components."

June 1, 2022

What’s New – June 2022

It's heating up here in Las Vegas and in the rest of the country. We've added some new tracks to the site and are constantly adding more tracks all the time. Here are some of the tracks we recently added:

If your track isn't listed on our site, let us know and we'll add it!

May 20, 2022

New Article for RacingJunk!

Check out our newest article posted on

Subtle Variations Can Make a Big Difference In a Racers Tune Up

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