Holley question, what do think of Vacuum Secondary vs "Double Pumper"?

For those of us who read all kind of stuff to learn things...........what is pinning a carb? I've never heard the term before.


Post 20 nailed it, but I use pin gauges, which are pretty inexpensive because they go up in .001 increments, where the number drills (which I have because you need them) go up in .003-.004 or something like that.

You can’t be quite as accurate with number drills but you can certainly get the job done and done well pinning with them.