I am tweaking this new rebuilt 235 and found sooty spark plugs and some dark splotches in the exhaust, so I want to tweak the carb a bit. The Jet has a 56 stamped on it. The numbered drill bit that will go through this stamped 56 Jet is a #53 drill bit.
Mike has a really nice chart that is in decimal, but with the above being the case on four different jets, I am confused as to what to go by. The 52 was too lean, the 54 was almost right, but I had to choke it just a hair too much. I am confused as to how Rochester numbered these Jets! Is there a conversion chart somewhere that converts Rochesters decimal system to ours? Are my chinese numbered drill bits that far off?