Advanced or retarded timming settings?

[crashmy911]

When setting my timming with light where should I set the timming. This is a three liter sc engine with 964 cam grind and the higher rpm valve springs. When we set the timming slightly advanced a knocking developed on the left side of engine. We turned the engine off quickly, now I'm waiting for some advice on where to go from here. Engine wasn't knocking when I did the valve seating for twenty minutes only after setting the timming slightly advanced?

[911pcars]

Hennie Youngman, of the quick retort-style of comedy and of "Take my wife .... please", fame also had this story:

Patient says to doctor:
"Doc, it hurts when I do this. What should I do"

Doctor says:
"It hurts when you do that? Don't do that."

The engine is telling you something with the timing advanced, don't advance it (as far). Try again.

I assume this happens during acceleration under a load (car moving). It sounds like detonation unless a chain tensioner suddenly decided to loose it's juice.

Hope this helps,
Sherwood Lee
http://members.rennlist.org/911pcars

[fredmeister]

I have a similar engine set-up. Stock piston and cylinders with 8.5 to 1 compression. 964 cams. Larger intake valves and high perf springs. SSI heat exchangers with Bursch muffler.
I can tell you that my timing with the stock distributor at idle speed of 950 rpm is 8 degrees before TDC and I have no knocking issues that I am aware of under load.
Make sure that the CIS is working properly....not leaned out.
Also make sure that the distributor advance works properly to give a maximum of about 26 degrees BTDC at 5500 rpm. The distributor has a habit of freezing the advance mechanism every few years. It is a must to lubricate it often by dropping oil down the shaft that is under the felt plug when you remove the rotor from the distributor shaft.
Some posts say for max performance to run out to 34 degrees BTDC at 5500rpm......but this would mean 16 degrees or so BTDC at idle with my set-up currently......I haven't tried this yet, seems like alot.
Keep me informed what you find.

[Wayne 962]

Just set it to the factory settings. Those Kraut-dudes seemed to know what they were doing...

-Wayne