Updated: Apr 15
I frequently get asked what to set the initial timing to on whatever perticular car and whether I have any dual quad distributors in stock. You can turn any 57 to 66 nailhead distributor into a dual quad distributor. Matter of fact, other years had similiar curves from the factory. All curves except dual quad 425s got detuned after the 400 trans got released in 64 "to keep people from breaking the tires loose." As for what to set the initial to, you can't go by the book. The factory nylon limiter bushings are almost never intact still. So if you set it by the book, it will over advance. there is no such thing as "setting the timing by ear," thats good way to inflict engine damage over time. detonation is no different than beating your engine with a hammer. You need 30 degrees total for stock and mild cams. no more than 34 degrees on big cams. almost all nailheads used ported manifold vacuum for the vacuum advance. on an edelbrock, that port is on the passenger side. if hooked up, you get misfiring, after setting your mechanical as described, then you need a limiting bracket or an adjustable vacuum advance installed. Base your initial off your required total. For $250 and a core exchange I'll recurve your distributor for performance, cooling, and fuel economy (with pertronix conversion). I do 2 to 5 distributors every week. Turn around time is typically 1 day. MSD also makes a good distributor. But the quality isn't even better than the stock distributor (which is bulletproof) and msd still has to be recurved out the box before being used. for stock and mild cams with MSD, use black bushing with one heavy silver spring and one light silver spring. . Stay away from all those garbage Chinatown HEIs... and those fake hundred and fifty dollar MSDS! they are not phased properly and arnt even usable. The 57 to 66 distributors also work on the 264 and 322, have a better breaker plate design than the early distributors. You can actually set the dwell through the cap. Aftermarket rotors don't fit well on the early distributors and vacuum advances are not made new.(we do sell rebuild vacuum advances.) I also get asked whether I will sell bushings and springs outright without my service. Unfortunately not, as there's many different advance yokes and weights depending on year and model which require different springs and limiting bushings. Its not a one size fits all.