The "P" stands for projected nose. On most 2 strokes the comustion chamber has enough of a pocket to give lots of clearance to run the "P" type. Hillclimber, the fine wire electodes like on the EV, EG, or EIX plugs run at a much, much higher temperature which is why they don't foul -they burn themselves clean. I found that my bike started noticeably better with the "P" plug, routinely 1 kick hot or cold. You should be able to get those at O'reily's also for $2. I never bothered with plug indexing on a 2 stroke since the intake charge mostly comes from the sides. Maybe I should. Cam.