sunmile

Hi guys since it's my first post on the forum I'd like to say hello.

I am rookie and wondering about buying new wheels for my IS250. I'm from Poland and my choice is very narrow since 5x144,3 system is not popular at all. I've found wheels which will fit my requirements more or less but I'm not sure about specs.
Which specs of should i go with if it comes to wheels and tires.

http://www.borbet.de/en/graphite-pol..._XRT/a-P000005

Wheels: I've planned to go with
FRONT: 8,0x18x35 REAR: 9,0x18x40 (i'm not sure about offsets, don't know how it should work or should they be the same? 35?)

Tires - I don't really know what to pick here. I saw 8 inches wide rims both with 225 tire or even 255 tire.
My purpose is to reach kind of upgraded look, that break even point which will enchance the overall appearnace (atm with 16'' rims wheels the car look like they were toys) BUT roads in Poland are poor. I mean most of them aint flat with ruts, bumps and holes. Thta's why picking 19 inches rims would make driving the car horrible.

So to sum up, I need ur advice about wheels offset and tires specs to reach a situation so my ride will be quite comfortable with a nice look of the car.

Sasnuke

Welcome Sunmile!

The wheels you suggested (18X8 +35 and 18X9 +40) will fit just fine.
Because those specs are very close to the F Sport OEM rims, you can use the same tire sizes found in the Owners Manual:
Front: 225/40/18
Rear: 255/35/18

If the roads are really that bad, and you need a little more cushion from the tires, then you could use:
Front: 235/40/18
Rear: 265/35/18

But I'd recommend the OEM sizes for the F Sport model.

sunmile

What would your recommendations be if I asked about bigger tires (Niche Vosso M204 which i rly like but sizing starts at 19'') would they fit in the arches? front: R19 8,5 ET35(optionally 45 - which would be better?); rear: R19 9,5 ET35

Sasnuke

Typical fitment for 19X8.5 is 235/35/19.
Typical fitment for 19X9.5 is 265/30/19.
That's already a plus one fitment to what the tire sizes should be for 19 inch rims.

At the sizes above you'd have to keep the vehicle at stock height...if you lower it there is a chance the rear might rub on big bumps.
But from the sounds of the roads where you are, I doubt you'll be lowering the car.

sunmile

What if I'd go with a tires 235/40/19 and 265/35/19? How will it influence look/comfort and possibly cause any problems like rubbing? I won't lower car for sure.

Sasnuke

The front would be ok, but the rear stands a good chance of rubbing with a loaded vehicle or over big bumps.
Also your speedometer isn't going to be accurate.