[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]
On 10 Jun 2005 at 11:40, Daniel Baum wrote: > > Detonation. Try backing your timing off about 2-3 degrees. > > OK. I did that. It is now timed at 0 degrees, which is actually by the book > for a 69. The timing light shows 29 degrees of maximum advance with the > vacuum hose disconnected. Before it was timed at 31 degrees. Okay, I didn't know that you were trying to run more advanced timing than suggested. It's really best to stick to the stock recommendation. You can certainly get more power out of the engine with more advance, but that will almost always have bad effects which will shorten the engine life. Advanced timing can lead to detonation (knock, ping, etc) because the flame front inside the combustion chamber is compressing the mixture ahead of it. If that compression gets high enough, parts of the mixture may ignite explosively causing the pinging that you hear, while also putting excessive mechanical strain on the engine parts. -- Jim Adney jadney@vwtype3.org Madison, WI 53711-3054 USA ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~