Physical Timing - How "off" can it be?

[genealogyman]

I posted this as part of another thread but realized it will probably get lost as part of that conversation.

How much can timing be off and still be "OK?" I guess what I am asking is how much do the various sensors compensate for the timing if it is a little off? I ran my AUTEL tool and Spark advance was at 18.5 degrees at idle. and it seems to idle ok. However, as I get to about 2000 rpm I can hear the engine rattling a little like "gutless uphill knocking" I just wonder if at the higher RPM if we have passed out of where the timing can be compensated for? At just over 2000 RPM the spark advance has increased to 28.5 and the MAF reading is at 32.91 g/s It seems to me they are doing what they should be but I work up a canyon and need this to get there. I am concerned if I put it under that kind of strain I could blow the engine. I have purchased the OTC 6488 kit and I am ready and willing to do the timing again, (last done with the full kit when the engine was out for a head job.) Just don't want to tear it apart again if that is not the issue.

 

[CDW6212R]

The timing can have a big affect just like an older engine with a distributor moved away from where it's supposed to be. The computer doesn't know how the cams or cam synchronizer is installed, it assumes they are where they are supposed to be. So it can make the engine waste gas, or be down on power, or tend to ping easier etc.

Using the timing tools are about the best way to do it.