Hi!
Need some wheel advise.
Will i be able to fit 19*11 ET 40 rear and 19*8,5 ET 52 on my S4...?

 

You can, but I wouldn't. To keep your tire diameter near stock you will need a very low profile tire. It won't take much of a hit to damage the wheels. I have 18 inch Panamera wheels on my car. That's as low a profile as I want to go....for safety and comfort.

 

What about 10,5 x 18 ET 51 in the rear on my s4..?

 

There is a comprehensive spreadsheet floating around here that shows figment and will help in making the right descision. I think it's in OA's signature.
I run Carrara III 18x11 et51. Running 295-35. The tires rub slightly on certain turns and articulation points and I have a passenger over 200lbs LOL. My fenders were rolled by the PO.

 

Ok,i'll Look for it. Thank's.