H&R "states" a 1.7 and 2.4 drop but that is extreme. 20's are perfect with these springs, you will love them. I called tirebuyer.com and they did the homework/math for me and everything turned out perfect.
Roush Stage 1 blower, Roush axle backs,MRT resonator delete,Roush coilovers,MM camber plates,Blowfish shifter bracket,Whiteline trans bushing,Steeda g-force brace,SR rear sway bar,Roush rear spoiler and heat extractors,25mm wheel spacers,and Ford Performance hood shocks,JLT oil separator,Flossy heavy weight shift knob and a newly acquired super speeder ticket!!!