What are the variables that determine whether or not vtec engages? I know oil pressure is a factor but what about throttle position, etc, etc. This came to mind while driving in 4th gear ~25mph(came out of a corner, didnt have a free hand to shift so i just let it go). The thing is that your speed climbs very slowly when in such a high gear but eventually it gets up into the 7 grand range, does vtec engage or just keep on revving on the original cam profile?

Ryan