Imprezagl

Hi I have 17x7.5 wheel but after I installed c speed full bodykit the wheel look small! Now I'm thinking to use rays te37 18x8 or 18x7.5 but will this wheel make the car have slow acceleration ? Will this 18 wheel hit fenders or springs when turn in corners or it will work fine? Which tire should I use if I will install the 18 wheel ?

Thanks