I had terrible spark knock on my '66 (which has very similar timing specs as '59), and after much trial and error and endless adjustments, the problem was fixed by installing a correct, new vacuum advance. Hasn't pinged since. I suspect the problem is that the initial timing is already pretty far advanced in early big blocks - 10 BTDC, as I recall for '59. Relatively little vacuum advance is used compared to '67 and later. Therefore, if the springs in the vacuum advance get weak, you get too much vacuum advance too soon. The result is pinging, especially on light acceleration when vacuum is highest. Of course, you need the highest octane gas you can find, as well as proper fuel delivery in the right mixture, and the engine running at the correct temperature. Even proper timing cannot overcome lapses in these areas. Correct vacuum advances appear on E-bay periodically. Don't buy a generic from NAPA - I can guarantee you it is set for 1967-and-later specs. And speaking of vacuum, a vacuum leak can lean out the fuel mixture, too, contributing to pinging. I assume it idles smoothly? If so, chances are there are no leaks. If it has a lumpy idle, look for a leak. Happy motoring, Chris H. 60 NY T&C 66 LeBaron --- Rex Crews <rexcrews@xxxxxxxxxxxxx> wrote: > Hi, Guys and Gals, > > I would like some feedback on spark knocking or > pinging on my '59. I have > changed the points, checked, set and re-set the > timing, and bought different > gasolines. Still, I have a weird problem with spark > knock on acceleration > and can even hear it at high speeds. The odd > symptom is, though, that the > problem is not consistent. One day it doesn't ping > at all, and the next day > it is terrible. My mechanic thinks the distributor > shaft is worn and is > shifting the timing, but the car has only 75,000 > original miles. Any > suggestions about the cause? BTW, my 60 and 61 > Imperials have zero spark > knock.... Thanks in advance. > > Rex Crews '59 and '60 Crowns, '61 Custom > > >