Rex, the main cause will no dought be the poor quality of fuel available now days, and this can change between every Gas Station or between each delivery to you local Gas Station. Here in Australia they drop any old junk they have left over into the fuel, high amounts of Ethanol, old stale jet fuel, just about anything really, so I bet they do the same in the US. To adjust your motor to suit the poor fuel you may need to run a lower advance, droping it back to say 5 Degres and if you have the spring loaded Vacume Advance you need to add some washers to keep that advance back a bit. The very simple equation is the worse the fuel, the less advance your motor can handle. I run my old Valiant ( 318 V8 ) on Propane, and because it has a higher octane than Petrol it never knocks, but if I change it over to Gas ( Petrol ) she will rattle it's head off when I try to work her hard, regards George. ----- Original Message ----- From: "Rex Crews" <rexcrews@xxxxxxxxxxxxx> To: <mailing-list@xxxxxxxxxxxxxxxx> Sent: Monday, March 08, 2004 8:20 AM Subject: IML: Spark Knock in my '59 > 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 > > >