I’ve had a lot of carburetors on my cars over my lifetime and have never had to drill holes in my plates. Never had to never will
Actually some Holley carbs come right out of the box with the primary plates drilled with a .125 hole in each one. Ron
Yes but technology has changed and carbs are more tunable now. And like you said some carbs came that way. No longer needed.
I still think it depends upon the carb and the application. Every Braswell 4760/4825 or Braswell-modified Holley 4150 I've seen over the years (and that includes what they're selling new today) has drilled throttle plates.
If you can't get the ide speed up where it needs to be unless you're off the idle circuit and the carb doesn't have an internal bypass air bleed adjustment that can be tuned, what other choices are there?
Exactly... Technology has changed but my old Holley DP (2-corner idle) and mushroom cam hasn't
With the transfer slots "square" on primary and secondary, and PCV operating, the only way to get enough additional air into my 451 with 272@.050 cam was to drill all four blades. Don't remember the size right now but think 3/32". Now it idles at 1000-1050 at 7"Hg.
Someday I'll spring for a 4-corner carb and have Thumperdart go through it
