what is dual vtec engagement?

[zerosilver19]

I found an ecu for my jdm gsr motor that i'm building to go in to my 99 civic ex and the ecu is a chiped ecu by mugen it says, it lists that it has dual vtec engagement at 4600rpm and 5800rpm. What does that mean i know vtec engagement in the 5k rpm range is good but whats does it mean when it lists it has dual engagement at those rpm levels? thanks

[strodda]

im not certain, but i think it has to do with throttle %. like if youre over a set %, then itll engage at 4600, and if youre under that % then itll engage higher.

[YellowITR479]

I think it has to do with the GSR Intake Manifold w/ has dual runners (believe on is long...the other short) and hey switch inbetween RPM for better performance. You can amost hear the manifold click if you have ever driven a GSR w/ a stock Intake Manifold

[SiGNAL748]

yellowitr is correct.

also check this thread http://www.automotiveforums.com/vbul...d.php?t=237961

[strodda]

i have dualrunners as well... when the butterflies open, that is not the first stage of vtec. but it is possible to have dual stage vtec. a friend of mine programmed it into his wifes gsr... and i was in the car while she was driving. depending on if she was cruising or at wot, it would determine what point vtec engaged. might not be a normal feature in ecu's, but it can be programmed in.