255s on stock R-Spec rims??

[Crusty Old Shellback]

Since the 245/45 19 tires are a factory option, One would think that they would calibrate the speedo for that tire. And since that is the last check on most assembly lines, I have no reason to think differently.

Mine came with the 245/45 19 tires.

 

[Jbo]

The Bridgestone PO4's were a Port Installed Option or PIO, the speedo was set up for the 235X45X19's and is slightly off with PO4's. you check with GPS.

 

[brfatal]

Just throwing in my opinion about the speedometer, if hyundai is like other car companies, they calibrate the certain car for the tires on it so the speedometer is correct. Like I have a 2012 ram and my speedometer is calibrated for the factory 275/60/20 tires, whereas my 2011 ram was calibrated for the factory 285/45/22 tires, and if the truck has the 17" wheels with 265/70/17 tires then the speedometer is calibrated for those tires. However if I was to swap wheels and tires on my current truck to the 285/45/22 I could go to the dealer and have my speedometer recalibrated for those tires

Your dealer cannot recalibrate for different size wheels. Your speedo is set for whatever it will be. All cars are calibrated for whatever the stock tire size for that model is, in this case 235/45/19. Even the ones that came with the optional Bridgestones, however the rolling diameter difference is not huge between the 2. Generally with every 2 sizes wider you want to go down one size in side wall ratio.

You're still wanting to run the wrong size. 255/40/19 is the closest to stock and will have the least effect on the speedometer and odometer. They will also have stiffer sidewalls so you will end up with better peak grip and steering response and the fact that they are a smidgen smaller than stock will in some minute way improve acceleration as you're raising your gear ratio. However you cannot run them on the stock wheels.

 

[RSPEC429]

I got what you're saying. Looks like I'm going to have to stick with the Bridgestone S-04s.

Looks like 245/40/19s could be an options as well. That would still throw off speedometer however.

 

[scottdk]

Please don't advise if you don't know what you're talking about.

255s will NOT fit on either 4.6L 18x7.5 wheels nor on R-Spec 19x8 wheels.

For a 255/40/19 tire, manufacturer specs require a minimum 9" wide wheel. Running this tire on a narrower wheel will cause excessive sidewall flex and will completely void the manufacturer warranty.

For a 255/45/18, manufacturer specs require at least an 8" wide wheel. WALLYMN is running an incorrect tire size.

My bad..........................................................

 

[Big_tugg]

Your dealer cannot recalibrate for different size wheels. Your speedo is set for whatever it will be. All cars are calibrated for whatever the stock tire size for that model is, in this case 235/45/19. Even the ones that came with the optional Bridgestones, however the rolling diameter difference is not huge between the 2. Generally with every 2 sizes wider you want to go down one size in side wall ratio.

You're still wanting to run the wrong size. 255/40/19 is the closest to stock and will have the least effect on the speedometer and odometer. They will also have stiffer sidewalls so you will end up with better peak grip and steering response and the fact that they are a smidgen smaller than stock will in some minute way improve acceleration as you're raising your gear ratio. However you cannot run them on the stock wheels.

is this Hyundai specfic? I've got mine calibrated by the dealer many times...not Hyundai though

 

[wd40]

I'm not looking at the wrong tire size. I want 255/45/19s... You misunderstood me.

Here is the chart so you can look at and compare the height, with and mph difference for the two tires. I think I will be going with the 245/45/19 when it is time to change.

View attachment Tire Size Calculator .pdf

 

[EXBMWGUY]

Here is the chart so you can look at and compare the height, with and mph difference for the two tires. I think I will be going with the 245/45/19 when it is time to change.

View attachment 2892

Ditto.