Technical Question about road draft tube vs PCV

Those are available repo and you use a V100 screw in PCV valve at the back of the carb. Those will fit a 62-64 Ford YBlock valley cover also……I wonder how that happened….same with the valve. (manufacturer suppliers)

 

Road draft tubes have to have air moving past the end of the tube that is moving fast enough to create a venturi effect to draw the fumes out of the crank case. Amything that obstructs the flow such as lowring, bent or shortened tube or something that deflects the air from flowing under the rig negates the function of the tube.