OK, so I'm late to the party.
Youse guys were right. This is, hands down, the best fix for Weber carburetors ever invented.
And it's not new idle jets or jet doctors or jet gurus or jet cleaners or anything that has anything to do with jets. My engine was jetted to perfection and just purred.
Well, sort of.
There was that little, almost imperceptible, nothing you'd hardly notice, wee bit o' fuzziness between when you first stomped on it and when noise happened and you'd start to move out. Nothing you couldn't get around by stomping down a little harder. Nothing worth bothering about.
Except, well, like it was always there. And OK, maybe it might have bothered me just a little.
In my gut I knew what the cause was, but actually doing something about it was harder than swapping in new idle jets and messing with the mixture screws. So, that's what I and most other guys with Webers would do every now and then when the old girl just needed a tune.
But last week, I finally got off my butt, got online, and got to work. Saturday, the brown truck arrived.
It wasn't that much harder than swapping in new idle jets. There was about the same amount of reaching for stuff that you can't actually see and maybe about twice as much cursing. But nothing you couldn't do in the privacy of your own garage.
I still don't know how it makes the Webers work better, though, since it doesn't connect to them in any way: