Need help with a Holley carb, here's what is happening: The car runs and idles smoothly. It drives very well....but under "hard" acceleration (usually shifting into third gear around 70 mph) there is a hesitation. The car would recover after two seconds and "come back" to accelerate. I originally felt like maybe the carb was getting to much fuel (until yesterday) I got on the car and it hesitated (a feeling like taking your foot off the gas) again...this time no recovery. I backed off the gas and the car still did not recover. A gently pressure on the throttle and all I got was some coughing and sputtering. After that I never got above 50 on the ride home. When I checked the carb, I expected to find gas everywhere. Much to my surprise the two rear venturies were covered with a black smoky residue. What is going on? Is there any fuel in the secondaries at all?