Automatics don't take as easily to high revs as a manual. If you are using the sportshift alot, or run it in high rpms, make sure to have a complete flush of your tranny fluid every 30k. Not the 50.00 drain and fill, but the 150.00 complete purge. If you haven't had the service yet, do it ASAP. As for VTEC engagement, VTEC only engages at 4800 when under hard acceleration. It will not engage when you are cruising or under light acceleration. It's a vaccum control, so the engement is pressure activated. If you are in 4th, you probably won't hit VTEC unless you put the hammer down and downshift to third or second, since 4th is a cruising only gear.