I've just replaced the QJet on my 1974 350 Auto. - It wouldn't idle when hot - turns out the air horn was warped.
So I've got a replacement from a 1975 Auto. This carb. is a big improvement, starts from cold first time, idles smoothly when hot (or cold) and the idle mixtures screws are responsive (which the old one were not).
The ONLY problem with it is that is leaves soot markson the drive from the exhaust tips when I back it out of the garage from cold. I guess it is too rich when on choke.
I have an electric choke fitted (which works fine in terms of getting the car running when cold) - I've tried truning it clockwise to 'lean' out the choke, but that doesn't seem to stop the black marks on the drive (that I'm sure the wife will not be impressed with when she works out what is doing it
Constructive comments please - (change the carb. is only partially useful!).
Oops - posted this in general - can I delete this ?