dan l

iTrader: (3)

When you go onto your 2 step you have to do so slowly. We were practicing with my friends 04 evo on the 5500 box yesterday. You bring the engine slowly to the launch box and then slowly put your foot to the floor. Experiment with how to do it while watching the logger. Any quick throttle movements, air movements, or quick approaches to a rev limiter or stutterbox will cause the ecu to pick up "knock". Is it real or not? Not sure, but at those loads its not dangerous. I've had 30+ counts on my stutterbox before.

I'm not sure what "rich" knock is. I've heard of it but never really had it. It may have to do with misfires which can manifest themselves into "knock". Lean is mean, try to get into the 11's at least on pump fuel if possible. On race gas get into the 12's or even mid 12's. The burn is much better and the chances of misfires and/or knock should be much less. I wrote code for my ecu to ignore the knock sensor with the clutch in. I'm trying to get ahold of the opcodes for the processor in the evo ecu's but can't find it. I need those opcodes to write similliar code for the evo's.

Watch yourself with blanket statements of 7 counts of knock is where you have to start worrying. While this is true in 99% of the cases it should be noted that very powerfull motors on race gas with a stock bottom end may not like 7 counts. The sheer hp per cubic inch ratio means that detonation quickly turns into localized hot spots which can quickly turn to detonation induced preignition and whammo big parts made into little parts.

The best thing anybody can do is just log a non modded car. After a few months you'll develop a sence of how to work with the knock sensor, learn to trust it, and learn when its giving bogus readings.

JohnBradley

iTrader: (30)

Rich knock usually manifests itself as over rich post ignition in the exhaust port. There are other variables that can also be called "rich" knock, but basically it comes down to bad tuning.