Classic/Antique Car Repair: 1950 chev pickup fuel system, psi test, return spring

Question
Hey Roger,
What could cause my truck to run fine up to 35 mph
and then just bog down as if there is not enough fuel.  Carburetor has been rebuilt, fuel filter cleaned.  I have done everything imaginable as far
as checking fuel lines.  Any ideas?
Thanks,  Linn

Answer
LINN;
hi;
  it sounds like a fuel condition , is the excil. pump ok, or is it cracked ? or the return spring bad.  you could have a kink or a spec of dirt in the line.The first thing that I would do is to take a fuel pump psi test  to see what kind of pressure you are getting to the carb.also take a look at the choke as it could be closing up on you. and check the points and cond. and rotor while you are at it.