the wheels are (F) 18x8.5 (25mm) (R) 18x9.5 (30mm)
the recomended sizes are (F) 245/40/18, (R) 275/40/18

beside the fact that the stock RE040's suck, what are the other consequences?

stock tires are: ( F) 225/45/18, (R) 245/45/18

 

you can run the stockers on there... not the best thing in the world to do since it isnt the greatest rubber... but it works.

here is a picture of stockers on LMGT4's

 

i'm assuming the handling sucks compared to the 245/40, 275's/40 setup

 

You can run the stock tires on the Nismo 18s but Nissan say that this will screw with the VDC.

Technically Nissan says you have to have the larger size tires plus
s tune susp, and sways to not screw with the VDC, but Jeff at performance nissan has plenty of experience with these without the s tunes and sway to make a judgement.

Even Jeff recommend the larger tires with the Nismo 18s.

Just what I have heard.
I have had my Nismo 18s for two weeks, with
245/40/18 and 275/40/18 Goodyear Eagle F1 GS D3 all around.
Best change that I could make the car. Better grip and better handliing. Love me.

See ya.

 

One downside of wearing rubber that is narrower than recommended is that when installed, the tire sidewalls are "spread" farther apart than intended because of the increased rim width. That makes the tire rim protector (which the RE040 does have) turn away from the rim and not serve its intended purpose of protecting the edge of your expensive wheel rim from being curbed first.

 

the diamater is the same with the 225/45 as the 245/40 so it works...

but handling is nothing like it would be with the 245/275 with the better rubber...