Air Density Online

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Renew or upgrade your existing membership here.

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.


Select ProCalc


Get 1 year of ProCalc including 4 jetting calculators and racetrack weather.
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Select ProTune


Get 1 year of ProCalc and get your baselines setup for you based on your engine.
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Select ProTune Advanced


Get 1 year of ProCalc and get a custom analysis and setup for your engine.
Learn more.

*Price is for the first year of use and includes analysis of one engine application. Renewing your ProCalc subscription in subsequent year will be charged at the current annual ProCalc price of $89.99.

The fine print:
-Payments are handled through paypal. Upon successful payment you will receive an email that will direct you to complete the registration process. Please check your spam folder in the event that you do not receive your confirmation email.
-All payments are good for 1 year. You must log in and pay again in order to extend your membership. Memberships are not automatically re-billed.
-Your contact information, including your email address, are never shared with third parties. A reminder email will be sent when your membership is nearing it's expiration date and we reserve the right to send occasional announcement emails.
-Questions and comments can be sent via our contact page.
-You can view our full legal and privacy policy here.


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