I was wondering on the slant six is there a cylinder that is on its intake stroke while another one is in over lap. I know on a V-8 this can make the engine think that its got a vacuum leak if the intake is an open plenum stile. If this takes place on a slant six then wouldn't you need to limit duration to keep a good flat torque curve? Thanks for any info. I'm looking to put a better cam in my 78 Aspen. I want it to look stock when I pop the hood but I want it to blow the doors off some of these rice burners.