At what RPM does the Honda i-VTEC engine engage?
1 Answers
Honda's i-VTEC system activates at 3500 RPM. Here are the details: RPM: 3500 RPM (listen carefully to the engine compartment sound). On the R18A1 engine, the VTEC engagement timing is set to potentially intervene at any RPM between 1000-3500, and beyond this range the VTEC mechanism will not activate regardless of how high the RPM goes. Working principle: When the engine exceeds 4800 RPM, coolant temperature is above 60°C, and the intake manifold vacuum meets factory specifications, the VTEC solenoid valve opens to direct oil pressure into the rocker arms, pushing the free piston to engage the high-lift cam. This extends intake valve closing time, increasing air intake volume at high RPM.