Engine Carburetor Rebuild Kit For Holley 600-850 CFM Double-Pumper Carburetors ProformIf you do not have hours to spend accumulating all these small parts, then the PROFORM performance rebuild kit is the perfect solution. The kit includes two size 110 machined needle and seat assemblies, needle and seat adjustment screws and nuts, three accelerator pump diaphragms (30cc x2, 50cc x1), two high flow 4 window size 6. 5 power valves, four non stick precision die cut gaskets for metering blocks, six non stick precision die cut gaskets for