Jeffrey262

This may seem like a silly question but, is there a disadvantage of putting 20" rims v 18" rims on a Mustang besides the looks? I have a Brand New 05 Roush Mustang Sport that came with Bullitt style rims (17"). I want to change the rims and enhance the suspension. Here is the package that came on the car: 6 Piece Aerobody Kit (Front Fascia, Rocker Panels, Rear Valances and Rear Wing), Rear Exit High Performance Exhaust, Exhaust Tips, Lower Valance Fog Lamps, ROUSH Embroidered Floor Mats, ROUSH Fender Badges, ROUSH Front Winshield Banner, ROUSH Sport Leather Seating, ROUSH White Face Gauge Cluster w/ Illuminated "Jack Roush" Autograph, Interior Dash Trim Kit (Engine Swirl Design), and ROUSH Pedals. I was thinking about adding the ROUSH Suspension System (Front Struts, Rear Shocks, Front and Rear Springs, Front Sway Bar) but I do not want a bumpy/hard ride. Will I get it with this suspension kit? If I add 20" rims will I have a problem once the new springs are installed? The kit say's the car will be lowered by 1-1 1/2 inches. Should I buy 18" rims and lower the car? Any recommendations?
Thank you,
--jeff

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