Last Friday, I had the '57 out at the track for the 2nd to last race of the summer season. I'm in the season points lead by one round's worth of points, first time in a long time I've been there. 1st time trial, the car just didn't want to pull to the shift point, was a tenth slower than I expected it to run for the weather conditions. Thinking it had been two weeks since I had run the car and the fuel might be a little stale in the secondaries, I went back in for a 2nd TT - not only didn't improve, got worse, I shifted 200 RPMs early, lost another tenth. Thinking the density altitude was about as bad as it had been all summer, I decided to jet down a step and see what happened. During that process, I thought the secondary float seemed to be pretty low, physically, but I had set it with the site plug before, so I put it back together, and went to recheck the float levels. The primary was fine, but the secondary was way low, only about half way up. Reset that, idle was terrible, fiddled with that for about 20 minutes, went out for my 3rd and final time trial - expecting huge improvement.

Nope, still as slow as it was for the 2nd time trial, really struggled through the RPMs. I figured it must have been the low float, not the jetting, so proceeded to put the original jets back in. As soon as I took the air cleaner off, I saw the PCV valve hose laying there - I never hooked it back up to the carb when I put the secondary bowl back on (I pulled the hose off because the bowl lip caught on the hose).

I went ahead and put the original jets back in, made sure the hose was hooked up, and answered the call for the first round of eliminations, dialing a good .05 sec fat. It worked, the other guy broke out, I ran it through 1000' to get a rough idea what I should dial next round, made it to the semifinals.

Most likely, when I first set that secondary float level, there was something in the needle/seat that held the needle slightly off the seat until there was sufficient pressure from the float to shut off flow. That eventually flushed out, lowered the fuel level, and left it running lean.

Moral of the story (not a new one) - check the basics before you go for the glamorous. The float level is the #1 "basic".