I tried a R-1 carb on my R-2 Avanti when I was having trouble with the
original carb.  I found out why they require sealing the screws on the R-2.
I was literally blowing gas out of the carb.
Paul Johnson

Dave T-Bow does a very nice clone carb - works great, looks right.

Rich,
   It sounds as if you created the problem by adding the pressure
regulator. As the boost comes up, it has to pressurize the pump as
well. Otherwise the pressure in the carb will be higher than  the pump
can produce. They sometimes refer to a stude pump with the pressure
line going to it as a "boost referenced fuel pump" Adding the regulator
has removed your fuel pumps reference.
     I had problems passing NJ state inspection with my R-2 it was
idling way too rich. The aftermarket R-2 fuel pumps are not sealed the
same as the factory R-2 pumps. Also the rebuilding kits-for a factory
R-2 are not the same as what came out of a stock R-2 pump. I finally
rebuilt my factory pump with a kit from Jon Myers.It matched exactly
what the factory used. My car now has no flat spots where it stops
accelerating.
    It would be much easier if I just plain E-mailed you some pictures
of the different diaphrams that I have been sold for rebuilding the
factory pump.
   Bottom line ,make sure you have a correct factory pump,get a
rebuild kit from Myers.Install the correct kit.It has 2 seperate seals
on the shaft.It also has a much stronger spring on it as well. Remove
the pressure regulator and go out and raise hell with it. If you have
any questions for me write to me off of the newsgroup, Joe Flannery