In a nut shell my 496 was tuned on the dyno before it was put in the car. Now that it's in the car it has ran great, but the only issue I'm having is that when idling the exaust will burn your freaking eyes out. Any recommendations? I did want to see what size power valves were in it after I checked my vacuum. I have 6" of vacuum in drive at idle and the carb has a #4 power valve in the primary metering block and a plug in the secondary metering block would you guys recommend droping to a #3 or is the #4 close enough? Primary jets 78-78 and secondary jets 86-86. Carb is set to highest vac seems to run great, but the exaust at idle will make you cry!