We have a dual stage intake. Its different, and does not make a big change in tone when it "hits."My buddy has a Celica GT-S and that thing sounds mean as hell when the variable valve timing kicks in. Since i'm a ZX3 guy hoping to convert to a SVT I was wondering if the SVT makes a similar change in engine tone?
Variable timing has been added to the intake camshaft, which is the first such application on a Ford vehicle in North America. Early Zetec I-4 engines had a variable timing system on the exhaust cam for emissions control, and now SVT Focus has it on the intake side to help increase engine performance.
Thats not entirely true, some cars loose power some don't. the one's that did loose power either lost it on top or on bottom, not across the whole rpm range. I GAINED bottom end without loosing anything on top, this was with FI but there were no changes in the tune between runs.VCT adds performance to the SVT, Turbo Tom has disabled the VCT and found he lost 5-6whp across the board