Is this a worthwhile project? I'm thinking a variable speed DC motor to spin it, a rock solid clamping system to hold it. a cam degree wheel to indicate off of. Then a stable 12DVC supply for the coil or module, then a source of vac for the advance/retard. a 2:1 gear set to get the speed right. then a RPM and dwell meter. Think its worth the time/energy to build? Or will this be an HUGE waster of time, energy and material? Keith
If it can be made for less than the cost of an old machine it might go over well. I'd love to have one in any case. A little software and it could generate the curve plots for you. Any sources for wiring diagrams or other info on how the old machines work? I've never had the chance to play with one. 383 240z ---> I have some experience with AC and DC drives, etc. Let me know if I can help.
few questions for those that have used them. Do the factory made ones use a 2:1 gear set? Or is speed taken right from the motor? I drew up a few mounting designs today, I like one of them. My favorite one is nice but on;y will work with SBC's if I'm gonna build it, I might as well make it fit all units. I'm off to search for any videos I can find of a machine in use to steal some design cues from. also looking for static photos. Keith
Well...you can do a LOT of the work on the engine itself with a carefully done set of timing marks and a light. You do need to disconnect the vac to study the centrifugal system thoroughly. Vac can be studied against the pump on a machine, but that is fairly unlikely to duplicate the infinitely variable vac plus centrifugal combinatios the actual car will produce, so it really has to be flogged on the road til you hit the limits of your engines tolerance.
I am loading up a working Sun 400 unit for the Marion Co swap meet next week. I want $500 for it and $600 with the lower cabinent...
The Jalopy Journal
