Originally posted by MrFatBooty
Secondaries aren't a "stage" of VTEC. More VTEC motors come without a variable-length manifold than with it. Hell just the sheer multitude of B16's out there probably is more than all other VTEC motors combined. Add the B17, B16B, B18C5 and F20C and yeah, that's a lot. BTW the H22 and H23 both have a variable manifold and the H23 isn't even a VTEC motor.
werd.
VTEC happens only once in a single sweep of the rpm's.
the initial sound change that happens in GSR with stock intake manifolds, is the butterflies in the secondary runners opening up. from this extra air, you get the extra sound (and performance)..kinda like getting an aftermarket air filter...slightly more air so when you floor it, it makes more noise.
when VTEC actually "kicks in", is when the pin get pushed and locked in and the cams are now using the VTEC lobe... THAT's when VTEC "kicks in" for lack of better terms.