WHEW! That is one giant, earth-friendly monkey off my back. TC is green again, passing with the lowest readings ever on CO -- 13 gpm with a 40 limit! Not bad!



How? Part of it was the tester was smooth on and off the throttle, but the carb tweaking I did had a big influence, since CO dropped 85% since last time!

After installing #52 jets in the Motorcraft 2150, the truck was running way too lean. I adjusted one of my two altitude compensating aneroids just enough until TC ran a little better.

Aneroids are devices developed for high altitude WWII fighter planes that allow more air into the carb to lean out the mixture, at higher altitudes using an atmospheric pressure sensitive bellows. I believe Ford tacked on electronic controls in place of the bellows to build a electronic feedback controlled 2150 prior to development of EFI.