Wideband idle tuning with large cams

To jbc426; I read your post #4 saying "it MUST be hooked up to manifold vacuum...". Whats your thinking on that?------And to the OP;are you saying that there is only 16 inches of pipe on the end of the header? In my limited experience with WB sensors, they liked more pipe after them. Seems that atmospheric air gets up into those short pipes giving erroneous readings.I had a car once with a 292/509 in it at 10.7cr, w/alum.heads, and RPMairgap. It did that too.The almost cure was 18* initial, cr bumped to 11.2, and a fair bit of work on the 750dp.Eventually I got rid of that cam. Put in a Hughes fast rate [email protected];more torque and more power and best of all a clean exhaust. I think most of the stink was in the overlap&initial timing.Hope this helps.