To add to more of the timing discussions, based upon my own experiences:
-Timing in an N/A car, I like to increase as RPMs increase. N/A cars are less prone to knock the higher the rpms with breathing mods. With restrictive exhaust, its usually best to keep its timing fairly flat
-Timing in a forced induction car, I like to keep flat from 4000 rpm and up. Increasing as rpms increase will typically increase KR, if your car tends to boost stack. It can be worth combating high rpm KR with a little extra fuel rather than reducing timing as rpms climb. If your boost increases more than 2psi over the mid-range, you have a lot of boost stacking and you may need to reduce timing 1* over 5600rpm and you'll need to address the restriction between your LIM and your exhaust tip to get the best performance.
-Timing is worth good power in the midrange around peak torque, but that's also where peak cylinder pressure is. Too much timing in the midrange is asking for a piston chunk or a blown head gasket.
-The above mentioned correlation between added timing and factory KR attack rates. If you're running a consistent 3* of KR for example, and you're running 17-18* timing with that 3*KR because you're running 20-21* overall timing advance, that's a big difference
Overall, timing is *free* power until you break something and timing can do that if you get greedy. I don't take that much risk with the supercharged 3800s that I tune when it comes to timing advance.
Originally Posted by gtpsleeper
