Class Calculator
When registering for an event, you can now use NARRA's new and improved Class Calculator to see which class of USTT or USGTC to run in. We highly recommend using the calculator BEFORE registering for USTT or USGTC events!
Check out the calculator below, and look for it on the left side of the page when you register for your next event!
Gather the following info BEFORE using the calculator:
- The weight of your car. (Don't know the weight of your car? Google it here >>)
This should include the car weight in pounds (including all fluids except fuel). - The driver's weight.
- The car's maximum rear wheel horsepower.
- If you do not know the wheel horsepower, you can calculate it using crank horsepower:
≈ crank horsepower - 15% = ≈ wheel horsepower (Use the mini Hp. Calculator on the right.)
- If you do not know the wheel horsepower, you can calculate it using crank horsepower:
- The tire width in mm.
Class Calculator:
ALL FIELDS REQUIRED!
Car Weight (lbs):*
Driver Weight (lbs):*
Wheel Horsepower:*
OR Your Approx. Wheel Horsepower
Calculated on the Right
OR Your Approx. Wheel Horsepower
Calculated on the Right
YOUR CLASS:
To move up one class, loose (lbs)
To move down one class, add (lbs)
To move up one class, add (hp)
To move down one class, loose (hp)
Example:
Car Weight (lbs): 3000
Driver Weight (lbs): 160
Horsepower (Rear Wheel Hp): 500
Tire Width (Width in MM): 275
=
Your Class: GT-1 or TT-1
Mini Hp. Calculator:
(≈ crank horsepower - 15% = ≈ wheel horsepower)
(≈ crank horsepower - 15% = ≈ wheel horsepower)
≈ Crank Horsepower:
Your Approx. Wheel Horsepower is:
