2012+ si with racing exhaust = high knock

[Garrett_si]

Does some people here have probleme with high knock retard when using a racing exhaust?

I tune a car with a high flow cat without knock retard and knock count, the customer change de DP for a racing one without catalitic converter, and we now have I knock retard (up to 20 degrees)

[Hondata]

Read the help about the way Honda knock control works

http://www.hondata.com/help/flashpro/kn ... tables.htm

There can be knock retard without knock.

The datalog does not show any knock, but the knock control is at maximum, which indicates that there was knock at some point before the datalog was made.

With race headers we have seen many cases where the pipe hits the sub frame and confuses the knock sensor.

[Garrett_si]

Thanks for help, I know how knock/ignition works

I will take a look the dp interference