Ok, I have read earleir posts on how it would not be good to have VTEC engage at like, 4000 0r 3000 or whatever. Why is this bad? My friend thinks he is cool becuase he has his set at 3500 (he has a civic Type R motor) I told him that is bad but I cant explain why.

 

Well, every Honda motor is different. For the F20C, you can set it as low as 5600 RPMs, anything lower would bog the motor down. I don't know how, but I just read somewhere that you would actully decrease performance buy setting it too low. In the civic, I don't know where VTEC is engaged. If the Civic engages it's VTEC at 4500 RPMs then maybe dropping it to 3500 RPMs isn't too bad. Just remember that it depends on the particular motor and car.

 

First of all, I'm going to assume you know what VTEC is and how it works mechanically. You can only feed your engine so much air/fuel per giving rpm and load. If you feed it more, like when in VTEC, under certain conditions (like too low an rpm) the engine will bog because it can't use all of that fuel/air. It's no different that people with 4 barrel carbs who lock the secondary barrels open from the start thinking they will get more HP sooner. The engine just can't take it.
So if it makes you "feel" good to say, "Yeah, my engine goes into VTEC right off idle!" You go with it, baby! I'll be waiting for you at the next stop light (after having gone into Starbucks for a cuppa.)