I recently purchased a 1959 Apache 3200 with a 235 inline 6. The truck has 63,000 original miles. From the beginning it has always and still starts easily without even having to choke it. It runs well until you hit approximately 1500 rpm's and it just bogs and misses. It does it in every gear and load is not a factor.

I thought a tune up would help. So far I have installed new plugs, plug wires, points, condensor, rotor button, coil, cap, fuel pump, fuel lines, rebuilt carb., cleaned tank, and installed inline fuel filter. The truck still performs the same.

Any suggestions on where to go from here.

Also I noticed a siver knob on the side of the distibutor about the size of a dime in diameter that turns. What is this for?

Any help and guidance would be greatly appreciated.