CA53W

Hello everyone, I couldn't find a "will it fit" thread for the 3IS so I'm asking here for help regarding which wheel offset I need without using wheels spacers.
My car (2015 IS250 F Sport AWD) is completely stock at the moment but after I get wheels I'm considering RSR Downs or Super Downs.
I plan on staying with the oem spec tire size. Yokohama Apex 225/40-18 & 255/35-18
I also read that incorrect wheel sizes can cause differential problems, so I hope I could get help to choose what I need to keep my car's reliability.

I plan to purchase a set of TE37 Sagas but need help deciding which offset to go with.
Here is the available offset from the website I have been looking at.
Front, 18x9 +35 or +45
Rear, 18x9.5 +22, +30, +38 or +45
I prefer a staggered setup with a concave look but whatever works best is good enough for me.

All help is appreciated, thank you everyone

Sasnuke

Based on the specs you provided, this is your choice for a staggered setup, and using the OEM tire sizes:
18x9 +35 with 225/40/18
18x9.5 +38 with 255/35/18

You could go larger if you like...here is my setup on basically the same car as yours, mine is a 2014:
18x8.5 +35 235/40/18
18x9.5 +38 265/35/18
I'm using Firestone Firehawk Indy 500 tires...which are a narrow fitting tire, so it clears the rear no problem, and I'm on RSR Downs.

CA53W

Thanks for the quick reply!
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Personally i want to stay at 18", but I'd be willing to go even wider.
What's the maximum width you'd recommend for 18"?
I have 18x10 available in +35
And 18x10.5 in +15 and +24.
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Sasnuke

If you go with a square setup, then 18x9.5 +38 is the widest.
If you go with a staggered setup, then front 18x9.5 and rear 18x10 +42...you might be able to squeeze an 18x10.5, but offset and tire size/brand has to be perfect at that point.

CA53W

Okay thanks again.
It looks like I'll be going with
18x9 +35 with 225/40/18
18x9.5 +38 with 255/35/18
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I'll send photos after I have them installed.

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