Air Density Online

Announcing: ProTune!
Get moving with your best setup!

Get the ProTune Package and get setup with ProCalc for your car or boat!

We have been assisting racers with their mechanical fuel injected setups for over a decade. We've helped racers make record-setting runs and we've helped racers get started with their first race. We've even written several articles about it. Now we want to help you!

Here's how it works: Get 1 year of access to ProCalc including access to 4 calculators, ability to export your data, and numerous help videos on engine tuning. You will also receive a questionnaire you will need to fill out. Using that data, we will create a custom baseline on ProCalc for your fuel injection engine combination and provide a write-up on how best to tune your engine.

get ProTune from

That means that an engine setup will be customized to your engine!

  • The racer will fill out a questionnaire regarding their current setup and their goals in racing.
  • We will use that data to set up your first baseline and save it in your list of available baselines in ProCalc.
  • Included will be a custom write-up about your fuel system, extensive visual guide for using ProCalc, and tips for engine tuning for your type of racing. Your custom baseline will be saved in the ProCalc jetting calculator for you to access as long as you have a ProCalc membership.
  • All material will be available in a downloadable format for you to keep.

We offer two options

With the ProTune Package, we will take data provided by you and set you up to use ProCalc with your ideal baseline setup. We will provide recommended air fuel ratios and notes to be aware of with your existing setup.

With ProTune Advanced, we will take your data and provide an analysis of your data from an existing setup, dynomometer data sheet, or fuel injection supplier and set you up with a recommended baseline. We will also provide recommended air fuel ratios and notes to be aware of for your recommended setup.


ProTune Package


  • ProCalc membership for 1 year
  • ProTune setup of your engine's baseline saved for your access based on an existing setup data provided by you
  • Downloadable custom write-up and record set for your recommended baseline.

ProTune Advanced


  • ProCalc membership for 1 year
  • ProTune custom set up from our analysis & development
  • Downloadable custom write-up and record set for your recommended baselines.
  • Custom analysis of your fuel injection combo to determine improvements such as adding a high speed, increasing fuel pressure for more response, or precision leaning out for more power
  • Analysis can include the following:
    • develop a setup for a new combination
    • convert an old setup to a new combination
    • conversion of flow bench or dyno test to the race track
    • calibrate ProCalc to a flow bench or dyno test result
    • low end, high end, ram air, high altitude tuning
    • convert to other fuels such as adding nitro

Get the ProTune Package

Get ProCalc for 1 year and get ProTune to get you started. Learn more


Get ProTune Advanced

Get a detailed analysis of your setup and access to the ProCalc 1 year. Learn more


I am using the ProCalc ProTuning information for fuel pressure analysis to get the best throttle response from the fuel injection system in our 305 Sprint Car.

— Frank Semerod, Slippery Rock, PA

I depend on the ProCalc calculator app. for my fuel injection tuning. I do not have to rely on my engine builder or prior flow bench test any longer.

— Bill Ketterman, long-time drag racer

The calculator does what no one person can do...unless you have thirty plus years in racing and know over 1100 computations. Get it right every time...

— Mike Shriver, SpeedSports

Get your car dialed in for any track, anywhere you race.

— Bob Szabo,

Helping racers with their best setup

Bob Szabo in action

ProCalc and ProTune were created by father-daughter duo Bob and Jennifer Szabo in order to help racing teams get the best jetting for their MFI combination.

Bob Szabo is a retired welding engineer, long-time drag racer, and author of 6 books about racing mechanical fuel injection at Bob has decades of experience in the automotive industry and as a drag racer. He has put that experience together in order to assist racers with their engine setups.

If you would like further information or have any questions, Bob and his web-developer daughter, Jennifer, will be happy to talk with you. Fill out the contact form and they will get back to you ASAP!

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.
-You have access to ProCalc for 1 year from the date your payment is received. You can renew your ProCalc membership annually for the current price of ProCalc. You will not be charged annually for your ProTune setup.
-As soon as your payment is received, you will be emailed a questionnaire about your fuel injection engine and you will be given immediate access to the ProTune area of ProCalc. However, the full setup cannot be made available until we have received your questionnaire and have had time to process your setup. Please allow up to 5 business days once your questionnaire has been received to finish your ProTune setup.
-Please be aware that we may contact you by email for further information regarding your setup. While we will work to provide your details as quickly as possible, we will not proceed until we receive all the information requested.
-If you have not received your questionnaire or have further instructions regarding ProTune, contact us for further information.
-You will have access to the ProTune data for the duration of your ProCalc membership. It is advisable to download the data provided for your records.
-Your setup is confidential, we will not access your ProCalc data after your setup is done without your permission. Let us know of your preferences. Regardless, we will not share your fuel injection setup information with others.

-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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