See this critter?

http://chevy.oldcarmanualproject.com/shop/1948_51truck/51ctsm0663.htm

Item #9 in this picture. It must be free and smooth in its operation.
This is the part that will cause a hesitation just off idle under mild acceleration. It needs a vacuum signal to pull it off the seat and add fuel at a tipping point. That gives a slightly rich mixture for just a moment and keeps the hesitation away at the transition from idle to run. You now have two of these and...much less vacuum to move each one. One of the many joys of dual cab set up. It will work, but these must be free and smooth in the bore. Good news? They are in the cover and can be accessed easily. I have put them in my drill and polished with 600 grit paper to make certain they are smooth and free. Be sure they are straight and move easily when installed. Should help with that transition.




Steve H