does my vtec swith on and off? at WOT, my b16a's vtec opens up at 4800 rpm, but i was thinkin, "if i'm cruisin on the freeway at 4800 rpm, will it open and close like crazy?" so will it? or does the ecu know not to activate the vtec at a constant rpm?

 

i thought about this before and rekon that it comes on at a slightly higher rpm than it goes off at (say 20 rpm). im not sure about this at all. but i do know that other control systems operate like this to save wearing of parts (hysteresis loop i think)

does anybody KNOW the answer to this? i'm just guessing

 

Yeah, the ecu will switch off vtec slightly below the point when it engages. like --> ben_vtec said.

Actually, the APEXi Vafc lets you set the point when it switches up, and when it drops back down. Not sure about the fields.


[Modified by RioNinja, 6:13 PM 9/18/2001]

 

If you are 'cruising' on the freeway, VTEC will not engage. PERIOD.

VTEC will only engage when the throttle is depressed beyond 75%. If you SLOWLY accelerate through VTEC, say with only 30% throttle, you'll notice that VTEC doesn't switch over.

If you are using a unit such as the VAFC or Fields, then it will switch over to the high cam regardless of throttle position. That is the only downfall for using one of those.