Posted by Todd Wilson on Thursday, August 07, 2003 at 11:51PM :
In Reply to: Re: Vacuum Gauge Reading posted by wally on Thursday, August 07, 2003 at 6:56PM :
Both valves slightly open is valve overlap. Designed to have the velocity of the exhaust gas going out help pull in new air/fuel and keep the continuous flow of air through the engine.
Todd