lowering VTEC engagment

[ChargeR]

Sorry, I should have been more clear. My questions about fuel economy and power were rhetorical. I agree with your comments above.

The point that I was trying to make was that Honda did not raise vtec to its stock point (6000rpm?) because of noise and pollution. They raised it for 'volumetric efficiency' of the engine. They used small exhausts with restrictive exhausts to reduce noise and catalytic converters to minimise pollution.

Your point here is unclear. Are you suggesting that Honda set the VTEC engagement point at such a high RPM because it it gave the engine superior volumetric efficiency?

[EK4R]

think mugsee means its more efficient with the restrictive exhaust system and cat OEM used...

i could be wrong though

[mugsee]

Your point here is unclear. Are you suggesting that Honda set the VTEC engagement point at such a high RPM because it it gave the engine superior volumetric efficiency?

I believe that Honda set the VTEC point at the (high) RPM point because it provides the most efficient output (power and torque) for that given engine when taking into consideration the state of the tune and associated components (i/e/h/etc).

If you set VTEC too low, the high cam will not be as effective as the low cam at that crossover point and those leading up to the optimum crossover. If you set VTEC too high, the low cam will not be as effective as the high cam in the lead up to the optimum crossover as well.