Also the online application calculates the difference in real speed and speedometer readings if the difference between tire 245/60 R18 and tire 245/45 R20 is significant. Calculate the difference in inches. If you want to compare other tire sizes, then select their sizes in the drop-down fields and click on the green button. Sizedifference between 215/45 R18 and 245/40 R18 tires. In the tire comparison table above, you can see a detailed calculation of the size difference between 215/45 R18 and 245/40 R18 tire. The calculation results are presented in the form of visual infographics, on which tire with size 215/45 R18 is on top, and tire with size 245/40 R18 below. BetterFuel Economy Factory Ratios Increased Power. vs 275/35-19 vs 255/40-19 vs 255/35-19. 245/45-R18 tires are 0.04 inches (0.9 mm) smaller in diameter than 245/40-R19 tires and the speedometer difference is 0.2%. Thedifference between the two tires is both in width and wall height. The 245 tire has a 75% ratio wall, equating to 183.75 mm, while the 265 tire has a 70% ratio wall, equating to 185.5 mm. In practice, the two could be considered the same height, just different widths as the smaller ratio of the 265 tires compensates for its larger width. Tiresize comparison. 275/40 R18 vs 245/45 R18. Calculate. CM INCHES. If your speedometer reads: Real speed is: Size difference between 275/40 R18 and 245/45 Thedifference in sizes and parameters between the 225/50 R18 tire and 235/40 R18 tire. Detailed calculations and graphics. Tire calculator online . Top comparisons; 225/45 R17: 245/40 R18: 235/45 R18: BetterFuel Economy Factory Ratios Increased Power. 245/45-R18 tires are 1.93 inches (49 mm) larger in diameter than 245/35-R18 tires and the speedometer difference is 7.2%. tyrereviewed on 2023-07-16 07:36:26. while driving a Cadillac 2014 ctsv. I also have a second set of 200tw tires/wheels for auto-x and HPDE days, so I At time of writing, prices were: Michelin $1,261; Continental $1,017; Bridgestone $981; Falken $815. $220 Conti rebate bright the ECS to $797. QE9kfUx.