Adjusting a Distributor on a vintage Sun Distributor tester

A demonstration of testing and adjusting a distributor on a vintage Sun distributor testing machine.

[@jamesford7182]

Wow. The last time I saw one of those was at the St. Louis Corvette facility. They used it to demonstrate the new HEI ignition system.

[@MrsOveata]

Holy crap. The bulb is working! They were hand blown and Sun couldn't get them anymore which made the tester obsolete. Nice.

[@steveperry1344]

i remember the machines but never had access to one. i used to do all my own repairs and tune-ups but i would only use a feeler gauge and timing light.

[@rubenambriz5300]

Hello.. how can I have you curve my distributor for my 66 Mustang?

[@chuckb9867]

Always check your distributor shaft bushings you can play all day and never get it right if both bushings are bad trust me I've seen it many times

[@paulnuebel5261]

Anyone interested in one of these 404 versions that works that I inherited from my grandpa? Awesome video by the way..!!

[@hankthebugman]

..set dwell and then check with feeler gauge???/..that is backwards...cool machine.

[@pattygq]

Is there a calculation for knowing what the distributor curve should come in and end at?

[@ronbell3358]

It depends on your engine combo, and what fuel you are using. I tune a lot of different types of cars. I can tell you that cars running off of the modern 93 octane fuels like less aggressive timing advance, less total timing. Back in the 80s I went to an automotive school that had a lot of old tools, one being a distributor tester. I used to use it to set up the distributors for my 69 Mach 1. It worked pretty good, you knew for sure what you were getting for timing at what rpm. Also you could optimize the dwell, that was important back in the days of running points distributors. Not much of a factor with modern electronic ignition systems. Back to the optimized timing curve, you will need a dyno of some type to determine what your engine combo likes best. Without a dyno to let you know how the engine performs with various timing rates of advance, and what total timing the engine likes best, you are just guessing.

[@buskman3286]

The shade tree method that always worked very well for max engine power without access to a dyno was to advance the timing until you got some detonation when accelerating in a high gear under load then back the timing off 2 degrees. Just as with a dyno, the final setting would be determined by the gasoline being used. So setting for max on one brand/octane rating might be too much (or not enough) on another brand/octane rating. Yeah, shade tree but it works!