I've had many a Lexus and traded my 2007 IS250 in yesterday for a low mile 2013 GS350 AWD.
I recently bought new wheels/tires for the IS and can't seem to find if they will fit.
They are 225/40ZR-18 Continental ExtremeContacts on 18x8 Enkei Performance rims.
Right now my GS has the 235/45-18 package.
Including a pic of my old IS for reference.
Thanks!

 

What's the offset of the IS wheels? Those may look good on the GS but may look a bit small cause they're only 18".

 

I was thinking that as well because of the low profile.
Offset is 50mm.

 

Are you planning to get new tires? Your current IS tires will be narrower by 10mm and overall diameter will be smaller by 31.5mm. Your speedo and mileage will be definitely be off. You'll be racking up a lot of miles in the car's mind in comparison to actual traveled.

 

That's what I thought as well. I'll probably add these to my collection of tires/rims that I've taken off cars I've sold and won't fit my new rides.
Thanks for the help!

 

Sell the new tires (ones on the IS) and mount the old ones (from the GS) on the new wheel. But double check if your calipers will clear before going through the trouble.

 

So 50mm all around? I think it'll fit cause they're so close in size with the stock GS, u just need a meatier tires.

This is comparing against my 19" FSport wheels.


Front


Rear

 

They're both 18's... just swap the tires.

 

18s will look terrible on the GS dude dont do it, might as well leave the stockies on for now.

 

But the stock non-FSport GS has 18's.

 

http://www.tirerack.com/wheels/resul...utoModClar=AWD

The Enkei RSF5 looks pretty close to the Advanti RN REIN. Choose your car color and then play with the wheel size settings and you'll see the difference between 18&19. Also it'll give you a basic idea of how these wheels will look on your car.

 

You are almost correct! The smaller tires will cause odometer to be off by about 5% which isn't too bad. I would be a bit concerned with the height loss of about 16mm or 0.6" and the setup looks too small on your car.
I actually did the opposite with my IS350. I picked up a set of Fsport wheels from a 2013 GS350.

 

Overall height loss of the tire is 31.5mm. But yeah. The height of the car is lowered by half. I was thinking along the lines of the circumference. Per revolution the smaller tires is short by about 3.9 inch. 5% over time is going to add up. Especially since my car is leased.

 

Took me a few takes to realize that was an IS350. Looks good. GS size tires or did you swap out for IS ones?

 

18x8 will fit fine on the GS350. The smaller wheels would mean you need a bigger sidewall tire to get stock diameter and that may not look as good to some people. However, you will get the benefit of both a faster car and better ride from the lighter wheels and bigger sidewall. So its really your call.

That being said, 50mm offset is going to look a bit sunken in from the side. I have 18x8.5 Enkei RPF1s at +30mm and they are not quit flush in the rear.

If you are a visual guy then the thing to consider is spoke design on the wheels. The RPF1s I have are black with the rim lip section and short spokes makes them look like 16s on my car. If your spokes runs to the wheel's edge it would enhance the visual of the size versus a wheel with a lip on it and shorter spokes. Stock 19s look good on the GS because of the spokes running all the way to the edge. If you get 18s with that type of spoke design it will look better. The design of your wheels will look ok on the GS as far as size is concerned.

I would go for something like TSW Bathurst if I were to replace mine with aftermarket lightweight cast wheels again in 18 size. 19 inch I would have to go for something forged to keep the weight reasonable.