so does that mean the tach-gauge is slightly off then? my car seems to rev into 9K around 9200 or so before fuel-cut comes into play.

 

when i shift my ap1 i light up the whole rpm bar ... therefor displaying 9500 rpms.... does this mean that the rpm tack is wrong/false????

 

all displayed measures of revolutions per minute are wrong to some degree. when you are driving 50 you are most likely 2-5 MPH off in either direction. when it says 9000 RPMs on your dash there is def going to be some degree of error involved in the calculation.

 

The tachometer is not that accurate - people who hook the engines up to external monitors have shown exactly where the engines cut out.

Also, near redline, the red rpm lines all flash - its not that you are actually at 9500 rpm.

Also, there's no point in lowering VTEC (too much) - the point of VTEC is to allow an engine to continue to make power at higher rpms - normally the power curve dips at a certain point and it doesn't make sense to keep revving. Basically, Honda's VTEC is two cam profiles that basically give the engine two power curves - one for "normal" rpms 0-6k, like on most cars, and another for extended rpms - 6k+.

For all S engines, VTEC can be lowered to around 5k-5.5k for more power/less mpg. Lower it too much, and the cam profile will make less power though.

 

The reason AP2s don't have such a violent shift into VTEC is because they make more power below VTEC - when Honda bored out the engine, it moved the whole power band lower. The result is more power down low so you're not waiting to hit VTEC to get any juice.

 

Each motor likes a different RPM to to engage VTEC. Looking at the dyno graph and seeing where the torque curve is most flat (between low and high cam engagement) is usually a good indication of where VTEC should be engaged. For the people who do lower their VTEC to around 4k don't see any less fuel mileage while cruising. The higher cam doesn't engage just by RPM, but also throttle percentage among other things. Also, the difference between the f20 and f20 is stroke, not bore.

 

Actually has to do with their MAP or whatever

Because on the updated 2.0L (F20c) engines in 2004+ models, the VTEC transition is also very smooth and the lower revs felt a bit more torquey than 2000-2003 F20c engines. I'm not sure how Honda did it, but the 2004+ F20c engines feel very much like the F22c engines if I don't know for a fact that the engines are different. However, the 2000-2003 and 2004+ F20c engines are very very different ...