initialA4

So I understand that if numbers are below 6 it is considered safe. Anything beyond 6 is considered dangerous? How would these numbers affect performance in terms of power?

CO AVANT

Yes. I have hit 8's in certain instances. This seemed okay with David@eurocode, but not okay with myself. The more knock the more the engine has to pull back timing, so too much and you'll start losing power. 0-6 is a good amount cf. Aggreeive timing allows you to spool faster.

bhvrdr

once the ECU pulls timing it is sensing knock and protecting for this. So the timing pulled is obviously timing not used. As the situation worsens you are actually losing much more timing than you could have been able to run if the program or hardware wasnt proper. In essence, properly timing the car or running the correct components that enable the pull to stay below 6 will keep the car from adjusting down the BTDC tables and give the best power and safety. cheers! Mike

diagnosticator1

As ignition timing is advanced, there is a reduction of exhaust temperature, and the magnitude of the high energy exhaust pulse wave front that precedes the main exhaust mass gas flow during "blow down period", is lower. That initial pulse of energy travels at the speed of sound from the exhaust valve through the exhaust manifold and is directed into the turbine housing volute that converts the kinetic energy of the blow-down pulse wave into exhaust gas pressure. Together with the exhaust gas temperature, exhaust mass flow and the energy of the blow-down pulse, these properties determine the energy at the turbine inlet for conversion to mechanical work by the exhaust turbine. Therefore, reductions of the blow-down pulse energy, and the exhaust mass flow temperature, will result in less energy at the turbine inlet for conversion to work, and thus less mechanical power to accelerate the compressor impeller. So, advanced timing results in slower turbo spool-up, not faster.

modwad

Thanks again to bhvrdr for this one. It really helped me when I got VAG and had no idea what these guys were all talking about.<ul><li><a href="http://www.audigeeks.com/forums/index.php?topic=561.msg4157#msg4157">Clicky on me, beeyatch</a></li></ul>