- Fri Mar 13, 2009 6:41 pm
#102993
"Harder it will hit" is the stupidest, most subjective explanation I've ever heard.
Okay maybe not. There's a lot of ignorant ricers out there that are overly concerned with how VTEC "feels". You never hear this kind of crap from people who understand how valvetrains work.
What your ass feels in the driver's seat is
a dramatic change in torque. You can't feel horsepower, and you can't even feel anything well enough to make an accurate judgment of whether you've improved power or not.
So the trick your ass is playing on you by messing with the VTEC crossover RPM is that torque massively drops off once you pass the ideal point, then it engages late and suddenly there's a big increase in torque as you catch up to the point of the dyno graph you should have been at. The truth is, you made your car SLOWER. It's the same thing as if you go light throttle all the way up to high RPM and then suddenly gun it. Does that make your car faster? NO! But you FEEL it. That's why you need a dyno.
Unless you've changed the cam, the OEM VTEC crossover RPM is ideal. Raising it or lowering it will only damage your power curve. Especially if you're not able to adjust fuel and ignition timing along with changing the crossover RPM.
Ideally you would not feel VTEC engage at all. The original VTEC is a very primitive setup with only two states, On or Off. The newest executions of infinitely variable valve timing are totally seemless. Where your power band would naturally fall off, instead it continues to climb steadily because the ECU adjusts valve timing, duration, lift, and hence overlap.
In short, the best point for the VTEC crossover is the point at which you feel the transition THE LEAST.
