I've been looking at a set of Advanti A4 Kudos rims lately and thinking about pulling the trigger, however i'm curious about the optimal tire width i should be running.

Currently im on stock 17x8's with the 225 and 245 rubber f/r.

These advanti rims are 18x8 +40 offset, and wheelsnext suggests 225 rubber front and back.

225 doesn't seem very wide for the rears and im worried about any lost performance (granted im driving a IS250 RWD and its not exactly a race car by any means). How wide do you guys think i could go for rubber on the rears without having any issues? 235 or 245? or should i just stick with 225.

these are the rims:



I know they aren't volks or works by any means, but i think they look nice and they fit the budget

 

I've been looking into this for a few weeks now and have gotten a lot of different information.

The stock 18" wheels for the IS350 are 18x8 and 18x8.5 and they run 225/40/18 and 255/40/18 respectively. The tires are a little fat in the back and you plan on running 18x8 all the way around so I'd say you would be ok with going 245s in the back.

Stock diameters for stock 225/40s and 255/40s are:
Front - 25.08661 in
Rear - 26.0315 in

If you use different than what stock is:
235/40 - 25.40157 in
245/40 - 25.71654 in

You want to be as close as what your stock came to so the speedometer and mpg don't change that much. Once again, I am new to this scene too. This is only what I have found out so far from reading the forums and from TireRack.

Guys, correct if I'm wrong. Thanks.

 

i think that is fine but to keep everything same and constant.. get it staggered if possible.. if not.... i think that is just fine

 

+1

Since you're driving a rwd, you should consider getting wider wheels in the rear, The car will look better if the wheels have a wide lip in the rear.

 

so should i be runnin on 235 since its a + 40 offset to be safe? or would i definitely be ok with a 245 width tire?

 

okay here's the thing you might wanna listen.... first... get a staggered... if you don't wanna compromise ride quality get 18s.. not 17s.. please... and you are firstly not using AWD so you should get staggered... so here's my suggestion.

18x8.5 +30 225/40-18
18x.9.5 +30 265/35-18 if they make it in that size....

Andre

 

lol yeah, i've been through all the wheel threads and i have a good idea for tire sizes on 8.5's and 9.5's at this point... however, it seems like no one is running 18x8's front and back so i don't have anything to reference from.

245 seems like it should be perfectly ok though.

 

gah... okay here's the thing.... wider rims and tires give you more stability and control.... a little but it affects your driving thats why the OEM 18s are staggered althoough only 0.5" but yeah go with our advice go staggered and you'll never go wrong... +40 offset has got nothing to do with how wide your tires should be... the tire width depends on your clearance and also your rim width... a 8" rim should be using 235/35 tops... 245 is just really too fat.... IMO...

 

245 is too small!!! u r not gonna get a flush look!! unless... u throw in some major spacers!!! like 15mm in the front and 20mm in the back!!! then it would look pretty good

 

because staggered is the way to go!

 

245 is the tire size.... to get the flushed look is the offset... and... with a 15mm front you'll be +25 and you might rub with 245... you definitely have to go down to 225 or 215.... and... the rear you should get somehting like 235 and go with +15 offset... but here's the thing...

GO STAGGERED... GET BETTER WHEELS.....