[arpad_m]

The 305/345 setup you're planning should work.

The front to rear ratio difference vs stock is +1.4%, which is well within the tire size difference range that the ECM can automatically compensate for. Those 345 rears will be almost an inch taller than stock, which will help with launches. Your speedo will read 2 mph lower than actual at 60 mph unless you recalibrate it in the tune.

Indeed you may need spacers to avoid rubbing the wheel well liner or hitting the suspension, I've never tried to fit a 345/30/19 tire.

Also, that 555RII tire has a W speed rating, so its max speed is only 168 mph. Just something to keep in mind if you want to do, say, a max speed run and hit 200 mph, because it won't be safe to attempt on these tires.