Air Density Online

Try ProCalc for free!

Set up your new fuel system using ProCalc!
Get 2 weeks free courtesy of Air Density Online.

With a ProCalc membership, you get 1 year of access to 4 fuel injection jetting calculators that will enable you to virtually jet your MFI engine according to the local weather and elevation. You also get weather updated much more frequently in the tracks list.

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or try ProCalc free for 14 days by filling out the form below:

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Features include:
  • Up to 8 cylinders with up to 4 jets per cylinder, 1 main bypass and up to 2 high speed bypasses
  • For normally (naturally) aspirated, blown, or turbocharged 4 cycle, 2 cycle, or rotary engines
  • For racing engines on methanol or nitromethane; also E85 or gas
  • Up to 3 Baselines for storing different engine setups
  • Calculate main bypass and system pressure
  • Re-calculate specific engine nozzles
  • Export data as a csv file
  • Calculations are based on air-fuel ratio which is a proven method of maintaining consistency
  • Access your calculations on your internet-enabled cell phone while at the track.
  • Ad-free use of the whole site
  • Track weather updated approx every 15 minutes

Fill out the form to start your free trial today!

Want to see what Pro Calc can offer? Try it free for 14 days and see for yourself!

If you have a constant flow mechanical fuel injection race engine running methanol or nitro fuel, try out Pro Calc for accurate setup and tuning. After 14 days, you will have the option to pay for a full year of access.

fine print:
-Check your spam folder if you do not receive your confirmation email. If the emails are sent to your spam folder, please whitelist the domain in order to receive future correspondence.
-Your email address is not shared with third parties. It is used to resend lost passwords and to send occasional announcements regarding your subscription.
-After 14 days, you can pay for the full year by logging in and going to the account page.
-Questions or comments can be directed here.


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