Have had the rochester carbs rebuilt on the A i am running a progressive linkage with a standard small block chevy. Noticed the jets for the outer carbs are 55 with 43 on the centre one is this correct?
If I remember correctly, I was running 55s in the center and 58's on the dumps on my 406. Check with these guys - they can give you a good starting point if you tell them your motor details. http://www.hotrodcarburetion.com/ Mutt
My 348 has 52 centers and 55s on the ends with a HUGE cam for the displacement (425hp/409cam,solid). Works really well. 43 is really small! I cant find them under 50 in any of my notes...........I would guess they are either custom drilled out or made for some dinky single app?
im running 58's in all 3 on my 348, works really well...43 is extreamly small, i would definately change that.
The 348/409 site says they use 61s on all 3 carbs. Interesting you useing 58s I will try them allso. My plugs are running real white on the electrode. John