It sounds like the pulleys are not aligned properly
i have bought bbk under drive pulleys and it seem to burn my belt bad after awhile i have replace the tensioner i put a lil bigger belt on and it seem to still melt the belt what do you think i should do ..
buy steeda ud pulleys bbk piggy back pulleys are DUMB yes they will slow your alt and water pump but you still use that big heavy harmonic dampner the steeda uses a one piece smaller SFI unit that is 100 times better.