I'm sure it didn't do much, but the performance gain is noticable. The car has 105k on the clock and Letting some B-12 sit on the valves for a little while must have done something. It's most noticable in the lower RPMs. I'd love to do a rebuild but I'm sure on my engine that would just be opening up a whole new can of worms. Plus i don't have the stones to do it myself.
