not likely on a coupe, on a sedan probably. i had that exact setup on a sedan and the rear passenger side rubbed. but it also depends on the manufacturer of the wheel. different manufacturers measure offsets differently.
it's likely to be the same, the coupe has a larger wheel well than a sedan so the profile of the tire shouldnt matter much (other than for speedo/odometer issues). its more the width of the rims, offset and width of the tires that matters more.
225/40/18 is closer to stock, therefore it doesnt affect your odo as much, but the ride will be a bit harsher than a 45 series tire. basically its just looks vs comfort.
also if there are lots of potholes on the streets around your area you might wanna think about getting a tire with a larger profile to protect the wheels for getting bent. if they're smooth the lower the profile the better lol.
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