6 pack tuning

I agree with crackedback on the timing, if you are sure it's right, the vacuum secondary springs are the next place to look. If it still has the yellow springs in it, they are likely too light allowing the opening of the secondaries too quick. The best way to do it is to go to each heavier spring until the bog is gone but it's a lot of work to take them apart multiple times so if you want to correct the bog AND TIMING had been eliminated as the culprit, then buy 2 sets of springs and start with the purple, if that still doesn't correct it then go on to the brown or black. Six packs are a lot of work to tune but when they are right, they are righteous! And yeah, Ma Mopar never put a 2 speed wiper motor in a six pack car for that reason, they were all 3 speeds due to the clearance issue with the air cleaner