Sort of a noob question. I know how all the wonderful tricks in i-Vtec work; ball valve in intake manifold to direct air through short or longer runners at certain rpm, oil pressure sensitive cam gear retarding or advancing cam timing according to certain rpm, and an oil pressure switch that locks in a third higher duration and lift cam lobe. But what about Vtec before the i? I believe it was the type R's that had a butterfly valve in the intake manifold, but was that it? What else was involved with regular Vtec?

 

Vtec is simply the "extra cam lobes" that effectively take over valve control at a fixed engine speed. The multi port intake manifold has nothing to do with vtec. The multiport IM was found on GSR motors, not type r's or B16's

 

Ok, so Vtec was just the third cam lobe, got it, thanks man.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BryanPendleton &raquo;</TD></TR><TR><TD CLASS="quote">multiport IM was found on GSR motors, not type r's or B16's</TD></TR></TABLE>

Thanks for the correction btw