I have a fairly steep driveway and the engine acts like it's not getting fuel. I have drained the tank, refilled with non-ethanol 87 octane, changed the oil, filter, fuel filters, plugs, wires, rotor, distributor cap, set the timing and set the carb to spec. The only thing I can think of is the angle of my driveway is causing the fuel to not fill the carb and run back towards the fuel line inlet