[blykins]

1. If you could post a picture of your very lifter, I could tell you. I can't remember when they switched to the pressure fed lifter; I think it was around 2005-2006. You could call and ask.

2. This all depends on the application and the camshaft. If used on a street roller grind on a toy weekend cruiser, then I would inspect them every couple years or 7500 miles or so. You'll get varying opinions on that. But if the valvetrain is setup correctly, it's a mild lobe, you keep the idle up, etc., they'll last a long time.

On your application, where you're not sure which lifter you have, and you've had it on a track, I'd go ahead and pull them now. Better safe than sorry. At this interval (5 years and track time), I'd send them back to have them rebuilt. If they're not Endure-X lifters, then I would probably invest in a set of those, or some Crower lifters, or even Isky Red Zone lifters.

3. The heads really aren't what shoot you in the foot on a 302 based engine...it's the deck height.