I just passed the 200k mark the other day on my EP I havent touched the tensioner or chain. Ive inspected but still looks good to what I can see. All engines are different from one another but whatever makes you feel comfortable do it. They always say if it's not broken then dont fix it. I say I may over do it when it comes to maint on my EP but it's lasted this long so it makes me feeler a little safer everytime I drive down the road. I did replace my water pump at 110k though. I may change it again here soon. I change my oil every 5k with a filer change at 3k. I change my tranny fluid every 10k. I use to change my iridum spark plugs every 15k but that became an overkill since these are 75 to 100k plugs. I'm still on my stock original clutch as well. I'll be curious to see how things last when I'm done with my k24a1 build.