I just purchased my first IS300 yesterday and ordered c8 sport SSD+ coilovers. I want a Stretched tire look with a very wide stance. i was thinking about running 18 x 10 in wheels with 235/40/18 tires. The only concern i have is if the 10' wide wheels are too wide. I want them as wide as possible. (planning on rolling & stretching the fenders if necessary) I will not go any lower the 9" wide wheels.

If you're willing to mod your fenders, then the sky is the limit when coming to widths. Just take into account the offset of the wheels and clearance of suspension components.

^^True. There's a member running 18x10 all around with a pretty aggressive offset. He's got a thread on here somewhere. Check it out

Yeah, I have been trying to find a good fitment thread but cant seem to find any info. i know the 18 x 10's wont be an issue in the rear, im just worried about the clearance in the front on turning angles.

My current set up is 18x9.75 +20 offset on 215/40 all around. Only had my fender rolled the fitment
is perfect.

Sigh...i'll never understand this whole obsession with wide rims, skinny tires, messed up fenders, and only getting 1/4 of a life out of your tires.

new idea. the xxr 521 wheels that i want are on back order so i am now looking at 18 x 9 enkei ls-5 wheels. these wheels have a +40 offset which im not too happy about so i was thinking about running a 20 mm spacer in the rear and maybe a 15 in the front. i think im going to run either a 225/40/18 tire or 225/35/18. any thoughts on how this will look? i cant find an accurate thread about tire stretch either.

can you post pictures of your tire stretch? 9.75in wide with a 215 tire must be an insane stretch. im curious as to what that looks like. i was thinking now about running a 18 x 9 with a 225

I'm running 19x10 et 43 and it is completely flush in the rear with a 265/30 only had to roll fenders. You don't need spacers the wheels will be aggressive enough with that low offset

Sorry read that wRong on the offset, I'd do a 10mm all round