Merlins Ralliart and EvoX TUNING GUIDE Version K.pdf - EvoScan

MERLINS RALLIART & EVOLUTION-X TUNING GUIDENotice that the timing @ 5224 rpm was 10° and after 6 counts of knock the timingwas pulled to 8° by 5500 rpm. 6 counts of knock pulled 2° of timing, in line withour prediction that 3 counts of knock will pull 1° of timing.So what is the ECU telling us to do to combat knock?We know from MTBT (minimum timing best torque) theory that we should advancethe timing until we either stop making power or we see the onset of knock. In thiscase we clearly see the onset of knock. So what we have to do is pull 2-3° of timingto combat the knock in that rpm range.Here is the way the log looked after I pulled timing. The boost was almostunchanged and the AFR was slightly leaner in that rpm range. Pulling the timingfrom 10° to 7° @ 5200 rpm cured the knock in this instance.Figure 28:IGNITION TUNING – WOT LOG, GRAPH #2, Evo9So my first approach when tuning is to eliminate the knock. This means that youmust retard the timing numbers (read fire the spark closer to TDC) in the HI-OCTANE SPARK MAP.REV: 0.K merlin@three.com.au Page 59 of 134