1973 pass, Nova, Chevelle, Camaro, Monte Carlo, 350/145 horsepower, A/T.
1112844 uses a stock GM vacuum advance of 1973502. B28 is a good performance addition, but needs at least, the rubber tube bushing on the pull pin, or it will give too many degrees of advance. Better yet, add a metal stop, instructions, with pictures, ask for them, [email protected]
- they are free.
Some of those engines are very emissons laden, and do not use much mechanical advance. Problems can be from gunk/grease loading up between the distributor main shaft and points cam, other mechanical advance parts, and/or wear on the weights and center scroll.
Test, pull the springs, weights off the top of the advance, and move the plate through its travel, does it run free, or is there resistance? Resistance, grease is stopping the free movement of the advance, clean shaft and advance parts.
Test, take the advance and move it clockwise, and let it go, if it moves freely, good, if not, dirty grease, other issues are in play, disassemble and clean.