Quote:
Originally Posted by BigFatFlip
What does "IAM" stand for again?  I've never really had the chance or the equipment to monitor my engine, so I just stuck with what "felt/sounded" better. My 6 mile daily commute to work is probably worse for my engine than a slight knock. |
Ignition Advance Multiplier. Basically when the engine is operating normally, IAM = 1.00 and ECU will allow maximum timing advance. When it detects some knock, it starts to reduce IAM and that in turn bluntly reduces amount of advance your engine is allowed to run. So 0.85 means you are running 15% less advance than you could be on better fuel. Due to poor octane content this is a common problem here in CA and also in Australia it seems. But for what it's worth, when I'm driving around and not paying attention to IAM, I could not really feel much of a difference between what 0.85 and 1.00 feels like. Then again, my butt is not that finely calibrated compared to others...
