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

September 1, 2022

What’s New – September 2022

We are so close to our goal of 1,000 courses on this site. We are less than 50 away! Keep sending in your tracks if you don't see them listed on the site. The tracks we added last month include:

August 1, 2022

What’s New – August 2022

We are slowly getting closer to our goal of 1,000 courses listed on this site. If you don't see your track listed here, we want to know! In the meantime, here are the tracks we added or updated in the last month.

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."

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