just bought wheels 19 8.5 fr and rear offset 45 both....help for best tires size

So you didn't but a staggered set up? Are you a RWD or AWD? On my RWD I had 19x8.5 and 19x9.5. Tires were 235/35/19 and 275/30/19. You can go with a wide tire like that cause the offsets are weak. A lot of people are running (myself included) Hancook Ventus V12. Check the vendor section for Tire Rack. They have one of the best prices and have reviews of the tire and it's performance on there.

Not staggered.. I got rwd

I have pirreli eurofi 235/45/19.what you think.

You will be just fine with Sffd setup

You want 235/35/19 like Mariano suggested. I believe this is close as you can get to stock rolling diameter anyway. +1 for Hankook V12's.