well it really depends on wat u wanna do w/ ur pony. 20s are alot more heavier than 18s and have alot more roll resistance, o and did i mention that theyre alot heavier? if u wanna go fast u should go w/ smaller wheels but if u have the money u could get 20s and then a different set for the strip.
|3rd carbon splitter|street scene GEN II window scoop|Alpina 15" subwoover| Streeet Scene full body kit|Rk- sport spoiler | california dream side scoop | Hallo frnot light | black turn signal | carbonfiber tail light| honey comp tail light dash
Go 20's it will look amazing. You could go wid a classic five start look with a foose such as the nitrous or the speedster or could go with a more complex five start pattern such as the df-5. Plus you always have people say ohhh its a foose.
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2005 Screaming Yellow V6 Mustang - 5 Speed Manual, In Dash DVD/Navigation, Eibach Pro Kit, 10" Black Stripes with 1/2" Pinstripes, 10" Sub Woofer with Sony Amplifier, 20" Foose DF-5 Rims with paint matched center pieces.
2009 Shelby GT500 - White w/ Red Stripes - Stock (For Now)
20 inch rims look so gotti on a mustang imo. Plus the ride with them is pretty bad from what I hear. Stick to 18s, those are more than enough. 20's make a mustang look so ackward.
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-A7X- ~Stang Syndicate Boston~*2006 Torch Red GT*10/10/07 Performance:Borla FRPP Stingers w/ True Dual Midpipes, Magnaflow High Flow Cats, JLT CAI, Bama 93 Race Tune, Ford Racing 4.10 Gears, Nitto 555 Extremes. Visual: Black AVS Tail Light Trim, Honeycomb Tail Light Vinyl, Black Racing stripes, 35% Window Tint, Trunk Blackout Panel, Billet Antenna Delete, Mirror Covers, 17" Konig "Further" Rims, Quarter Window Louvers, 20% Tinted Head Light/Turn Signal, Boss C-Stripes, CS/GT C-Scoops.
Roll resistance... the bigger your wheels, the harder your engine has to work to get them to spin faster. It means the bigger your rims, the slower your car. Personally Id go with 18s and lower your car.
two of my friends have 20"s and Eiabach pro-kits... the ride is stiff, but still pretty nice, not uncomfortable at all. get any size you want, 20s will look good.
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2005 Mustang GT - ROUSH CAI, FRPP Stingers, Silverhorse Blackout Panel, Brushed "Aluminum" Dash Kit, chrome American Racing ROGUE wheels 20x8.5 with 255/35/20 Yokohama S.Drive tires, ROUSH rear springs
I like the look of 20's for show cars, but have to agree that they will slow you down speed wise. If you want to race your car, getting 20's might be the wrong direction. If you want to look stylish then 20's will probably work for you. It all depends on what your goals for your car are.
I have the Foose Nitrous 20's on my 06 GT, with Ford suspension pack. The ride is stiff but it handles like it is on rails. I am running Nitto 275/35-20 on rear and 255/35 20 on front.
18 with some low profile tires seem to look bigger than with normal tires but if your goin for 20's make sure to get some light ones its so much harder to spin the tires with heavy rims
2006 V6 Mustang... Need advice on 20 inch wheels 
