There is a post here *somewhere* that described a clear intake manifold used to test meth kits to see where the meth ended up when sprayed like for kits like mine. (single nozzel high output spray). As it turns out more meth typically ends up in one bank versus another due to swirling under heavy spray where not all of it evaps..
*As a crackpot theory* one bank is running much cooler than the other. And the step colder plugs prevented self cleaning/high temp insulator burn off and the combo == my front back of sadness after just 10k miles.
in my case the front banks were extra carbon cripsy .. and not good like a nice steak carbon. the backs were much cleaner.. but also fouled to a degree worth replacing.
Back bank,,, not nearly as bad as the front. but bad enough to warrant replacement as they were only going to get worse with time.
