disortion in quieter than clean!

yo, i have a crappy roktek distortion pedal, a peavey rage 158 prac amp and a peavey predator plus. when i play clean, i can get a decent vomume out of it, but when i stamp on the pedal, it goes real silent and washy as hell! all the pedals controls are on full, and still it's really quiet when compared to the clean. i need some serious help, as this is pissing me off a treat.
# 1
The only advise i have or you is to throw out the rockett and get a Boss MT-2 metal pedal (hey that rhymes).
"I need a girl who's as hot as my guitar."
# 2