Okay to Go From OEM 225/55/18s to 275/40/20s ?

[OhThatGuy]

This would help eat up some of the gap in the wheel well but it is over 3% larger in diameter which one site warns results in the potential for brake failure. Any tire experts able to weight in on exactly what aspect of the increased diameter results in potential brake failure? The overall wheel+tire weight difference is pretty minimal.


It eats up the gap in the wheel well nicely compared to the 285/35's from the GT-R. Here is a photoshop of what 275/40/20s would look like...

 

[OhThatGuy]

Well, I'm thinking of taking the leap as I have a local buyer for my 2 rear GT-R runflat 285/35/20's. Toyo Proxes 4 Plus in 275/40/20 can be had for around $710 shipped (for all 4!). Hopefully going up just past 3% in overall tire diameter doesn't mess up the electronic nannies.

 

[OhThatGuy]

Got the 275/40/20 Toyo Proxes 4 Plus tires all around today. Notice that it is about 1.1 cm higher but with 1.1cm less wheel well gap. No rubbing noticed yet and the lighter tires (10 lbs. lighter each than the GT-R rear runflats) feel great. As minor as 1.1 cm is, you feel that slight jump in ride height when you first sit in the car. I wish I could drop it 2 cms from where it is now. The 275 width rubber is perfect and cures most of the excess poke that it had with the 285's out back.

 

[JasperEdwards]

Assuming you end up doing this, what are your plans for your existing OEM wheels and tires?

 

[GEE50FX]

Assuming you end up doing this, what are your plans for your existing OEM wheels and tires?

He got rid of his EX.