Wondering if I dun goofed
 

I recently got new wheels and tires for my car and I think I may have chosen the wrong tire size.

Wheels are 18 x 8.5 and Tires are 245/40 R18

This wheel and tire combo increases the overall diameter by ~27mm (~1 inch)

In hindsight I feel like I should have gone with 245/35 R18 or 235/40 R18

Is this 1 inch increase in diameter too much?

What impact will this increase have?


Thanks in advance!

It will basically increase your overall gear ratio. Which may have a little effect on how quick your car is, but will give it a higher top speed (and higher in each gear)

It will also change the accuracy of the speedometer. Chances are it read a few MPH faster than you were actually going when stock. Now it might read a little slow. Remember this will change depending on speed. For example now you might be going 31 and only show 30 and might show 70 but be going 74.

You can do some measurements and a little math and get a good idea of where you will be.

According to this: https://tiresize.com/calculator/

Your actual speed will be 4.5% higher than what your speedometer reads.

It'll make the car feel slightly sluggish compared to stock and possibly look a little odd. If you're not tracking your car, you shouldn't have much to worry about. Like others have said, just keep in mind that your speedo is going to read lower than your actual.

You'll find that the speedo reading lower from your tire diameter change is pretty much offset by our cars reading faster from factory.

Go download a GPS speed app and drive at a constant speed. Look at your speedo and compare it to the app.

It's also going to affect your grip levels and balance. If you have not done any power mods, it'll make the car harder to drift and probably a little more boring to drive.

In short? Yes. You goofed.

Just curious.. did you see the thread under this and then started to think you goofed?