im using 30k atm and im bashing.....if ur bashing u might want around 50k or so even more....100k....a dude that was racing his 4.6 ss had 50k front and back......i dont race alot but i bash like hell.....i got the 4.6 ss and its pretty good...if ur racing u might want around 10k or so...but for bashing 30k is good and i bet 50 would be even better