When I had my 489 cu in built it was dyno'd to 'prove' HP and TQ output. However being an engine dyno it was tested for maximum power and not part throttle or lower rpm use. Consequently when dyno'd it would have been running-off primaries AND secondaries on wide open throttle and therefore not representative of typical use.
The car drove OK'ish but had a huge flat spot when accelerating on primaries. Inspection of plugs showed a white colour - obviously too weak. I re-jetted the primary main jets - after several attempts and 5 or 6 larger jet sizes I eventually 'nailed-it' (old-school style).
However whilst primary jetting was 'spot-on' it was certainly still showing a degree of hesitation when 'cracking' the gas pedal - and really indicative of an insufficient primary squirter 'shot'.
Again much like the primary jetting I had to experiment with primary 'squirter' sizes - and eventually I settled on the largest size Holley makes - with some tweaking to the squirter 'delivery' with the operating cam I eventually got perfect response.
Secondary jets - probably little need to worry too much about these other than to be sure the engine isn't running too weak on wide open throttle (unlikely) - they are only used infrequently and for only a few seconds (unless being used on the race track) my carb is a 950 cfm - I know the main jets are quite rich (I've comments from people following me when I 'nail-it' that their eyes water from the fumes......I'd rather the safety factor of engine running rich than too weak at WOT. In real terms secondaries are only ever used infrequently and will make little difference to fuel economy unless you are frequently 'pushing pedal to the metal'........
You did check that you get a continuous squirt of fuel into each barrel as you actuate the throttle?
,Yes Two nice continuous squirts. While on the subject of carbs, all the manual choke seems in situ with just a cable and pull required into the cabin. Any thoughts on whether it ‘d be good to fit one as just pumping and feathering the pedal is a bit hit and miss, many others done this. ? If its there it seems to make sense to use it.