493 carburetor tuning question

Mattax has you going in the right direction. When tuning any carb for the first time always get brand new plugs it in first, then get your timing at idle correct and you would want something in the low 20*s without vac advance with that cam imo. Then get the total set at about 35* without vac advance. Then get the tune on the mix screws and they with end up some where between 1-2 full turns out and all 4 should be exactly the same turns out. The idle blade screw will be about 1.5 turns out to get the t-slot exposed, you will have to take the the carb off and check. Adjust both pri and secondary t-slot with .020 exposure. If your mix screws need to be less than 1 turn out you will need to change the IFR to a smaller one. If the mix screws are not out enough you will have a stumble because these screws initialize the fuel transfer when you crack the throttle. Check your plugs for how its burning. should be fairly clean on the base circle on the shell of the plug and the ground strap should show the burn to the bend of the strap, if its burned to the weld its too much timing and if its on the tip not enough, on the bend is just right. Others things can influence that as well like different fuel as the ground strap is a heat indicator, but is does help to get timing close. Yes, also make sure the float level is in the middle of the glass with the new holleys and at the bottom if you have the brass plugs before you start. Hope this helps

Thank you, I'm hoping this random April snow will go away so I can get back to it. Only have time on the weekends to work with it.