Holley carb off idle bog/hesitation

[Jeff H]

I finally got the T-block fitting in and put the new fuel lines/T-block on the L78 and got it fired up and running without a leak. But I'm getting a little bog/hesitation just off idle. This is with a rebuilt by me Holley 780(4557) with stock jets(72 and 70 I think) and a 9.5 and 8.5 power valves. I tried advancing the timing a little to see if it would help but didn't seem to. I tried adjusting the accelerator pump bolt but it didn't cure it either. The carb has the stock acc pump cam too. I'm wondering if the secondaries aren't quite closed all the way and air is getting past causing the bog. Open to any thoughts on getting rid of the bog. I'll pull the carb and check the secondaries but what else can I check without opening up the carb?