Tire size and speedometer

Down-sizing or installing a shorter tire will cause the speedometer to read a faster speed than you are actually driving. Or lower if you have gone with a smaller tire than stock.

Another tire size calculator we have is our speedometer correction calculator.

Tire size and speedometer. When you go to bigger tires the circumference of the tires is larger meaning the distance around the tire is longer. Thus with each revolution you are traveling further than before. Therefore your actual speed is higher than your speedometer reads.

Or lower if you have gone with a smaller tire than stock. Down-sizing or installing a shorter tire will cause the speedometer to read a faster speed than you are actually driving. This is because the smaller tire will have a smaller circumference causing the tire to travel less distance per rotation than the original equipment tire.

How a Change in Tire Size Affects Speedometer Accuracy When you change out your tires and wheels for a larger wheel you always want to respect the overall diameter OD of the original tire. A lower profile tire must be placed on a larger wheel to keep the OD close to the same as the tirewheel combination being replaced. Tire Size and Comparison Calculator Calculate tire diameter from code and compare speedometer differences for tire sizes.

The first number is the tire width in millimeters. The 2nd number is used to calculate the sidewall height or aspect ratio by percentage. So the sidewall height of a.

Altered Tire Size For those who have off-road vehicles and put larger tires on for better performance on the trail the speedometer will be affected. Since there is more surface area and a larger circumference on the outside edge of the tire the wheels will actually spin slower at any given speed than the stock setup would. Why does changing the tire size affect the speedometer.

Most vehicles have a speedometer that is calibrated to the tire size that came from the factory. If you change the size of the tire you alter the total circumference and the amount of travel per rotation. If you know specific information about your vehicle gear ratios RPM etc then use the Gear Ratio calculator its probably a little more accurate.

Speedometer Check in MPH Orig Tire Dia. Formula used New Tire Diameter Old Tire Diameter Speedometer MPH Actual MPH. Changing the stock parts including the vehicles tires can throw off the speedometer calibration.

Larger tires cause the speedometer to read a speed slower than the vehicles actual speed while smaller tires cause the speedometer to read a speed faster than the vehicles actual speed. You may recalibrate a speedometer in a few simple steps. When your speedometer reads with the new tires your vehicle will actually be traveling at which is than the original tires.

The overall diameter variance of the new tire is which is different than the original. You should never go beyond 3 of the original tire otherwise you run the risk of brake failure. A very useful tire calculator when searching for tires that are a different size than stock.

Another tire size calculator we have is our speedometer correction calculator. This is valuable if you plan to or are already running bigger tires than stock and want to know the speed you are actually traveling compared to youre speedometer reading. A bigger tire has a larger circumference thus traveling a further distance for each revolution.

How Tire Size Affect the Speedometer. There is a sensor where the speedometer is attached which is able to detect the turning speed of the wheel. The programming of this sensor detects the speed according to the tire size which came from the manufacturer.

Using a different tire size like this isnt a radical change. Its about 12 wider and approximately 12 smaller in diameter. However there will be some negligible speedometer differences of 14 your speedometer will overestimate your actual speed by 08.

Larger tires cause the speedometer to show slower speeds than reality and smaller tires show faster speeds. You can reprogram a vehicle when changing tire size using an on-board diagnostics system or OBDII. OBDII systems are in most cars and light trucks and were introduced in the mid 1990s.

This diagnostics system monitors parts of the chassis accessory devices as well as tire size. If youve installed tires that are larger or smaller than original equipment tires or if you have installed a ring and pinion gear set with a different rear gear ratio the Speedometer Calibrator allows you to correct speedometer and odometer readings. The Flashcal for Truck is your answer.

Its a handheld automotive calibration device that adjusts your trucks speedometer for aftermarket wheels tires and gears. Is it Easy to Use. Flashcal is big on easy.

Just plug into your trucks OBD-II port and select your new tire size or gear ratio and your truck is calibrated. Product description Hypertechs Speedometer Calibrator can correct the speedometer for tires up to 54 inches depending on the application andor non-stock rear gear ratios. Speedometer gears are quick and easy to install with simple hand tools.

Also suggested is the purchase of a new speedometer O-ring to prevent any leaks on the new installation. Check out all of our Speedo Gears here. 93-06 Short Shaft Electric Driven Speedometer Gear Chart.

Ram Speedometer Calibrator 18-20 Ram 1500 2500 3500. Calibrator helps you quickly and easily reprogram your vehicles speedometer to match the output of your larger tires. Your vehicles computer is designed to track the speed based on your stock tire height.

When upgrading to larger tires there will be a discrepancy between your.