notchback11s

i just got a 1988 notchback a month ago and when i first got it there was a slight knock seemed to be comeing from bottom of both heads! the guy that sold it to me beat the **** out of it before he sold it to me the next day the knock was gone and stayed gone until i rev the engine up to 5500 or 6000 rpms! i just took my plugs out and the are oiled up! it has a erson cam 512 lift
with stock e7 heads ported with dual valve springs. i know i have a intake leak just tested it yesterday with some pb blaster, so my queistions are could my intake leak cause the oil build up on my plug and cause detonation and the knock or do you think it more likly something like the valve guide! or something in the heads?

straight6racing

pull your dip stick and oil filler cap. if smoke is pouring out you have worn piston rings or worn valve guide seals. it is not likely that the intake leak is the cause of the oil on the plugs, but it could cause knocking if it is running lean.