Too much dwell can cause a late spark, rough running, lack of RPM potential, early point anc condenser failures. The closer the points are to the point cam, the larger the dwell. The point adjustment is simply how close each point set is to the point cam. The dwell is controlled by the design of the distributor (distributor point cam, point design, and adjustment). When running, you can then check the centrifugal advance and its rate with a simple timing light, revving the engine up to 2,000 in steps with a tuneup tach and timing light. Measure crank pulley, compute how wide a degree would be on the circumference, and mark it off up to about 30 degrees in maybe 5 degree steps. Static time it to the stock mark for ually close enough for a starting point. If gap needs to be altered to get total dwell right, you mess with the first set of points to open, not the second one that controls firing. ![]() Repeat with other set, then repeat with both working. Hook up flashlight type light across points, stick a piece of paper between one set, rotate distrib and see how many degrees light is on. You can't study rate of advance without either a running engine or a distributor machine, but if advance is stiff you will likely be needing lighter springs-Older Mallorys at least often use two very different springs, a very light one to allow quick start to advance and a heavier one with some slack that takes up later in the curve.ĭwell: Setting points to spec will getit close enough usually, but better is to check so: 2 numbers, dwell for each point separately, dwell for both working together which will be roughly 10 degrees more. ![]() There is an adjustable stop in there somewhere to reset total, don't remember details. In other words, you are hoping for about 8 which would be 16 crank. This is distributor degrees of advance, multiply them by 2 to get crankshaft degrees. Repeat several times with eyeball right over it til you are satisfied marks are accurate, measure on protractor. Now grab the rotor and twist it in the direction of rotation till it stops, marking off starting and stopping point on rim of distributor. This is of course a starting point for experimentation-every engine has its own tastes.īefore engine is running, study it so: Get a degree wheel or protractor and either bore it out with a holesaw or make a special fitted one carefully drawn on cardboard so it fits snugly over distrib in place of cap. do I just set the point gap on the leading and trailing points then adjust the trailing points until I get the correct dwell?Ĭlick to expand.You probably want about 4 degrees static and enough centrifugal to take it up to about 20, and the curve should be fast, starting in right off idle and getting done before 2,000. My biggest question is setting the dwell on this thing. anyone happen to know what recurve kit I would have to order? also, someone mentioned a replacement condensor from napa, would anyone happen to have the part# for that (just in case kinda thing). ![]() I've heard you can get advance recurve kits from mallory to set these up with the right advance for a flathead instead of a SBC. I'm gonna set the initial timing around 5-6 degrees. question is, what should I set my point gap and dwell at. it's got about 7-10k miles on it with no problems yet, points cap and rotor all look new. it has been pretty good up to this point despite all the bad mouthing I hear about them. I have a mallory dual point in it that was purchased and installed in about 1992. I'm going to be resetting the dizzy in my dormant flatmotor tonight and was looking for the generic starting points. ![]() Hey guys, I've searched around the flathead ignition stuff and still have a few questions.
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