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

MERLINS RALLIART & EVOLUTION-X TUNING GUIDE5.04-IGNITION TUNING – STOCK HI-OCTANE SPARK MAPThe HI OCTANE maps for the same model and year are frequently different fromone country or region to another. The inference being that the maps are set for thelocal fuel and its octane rating.JDM maps typically have the most timing under boost and are probably intended torun on 100RON fuel. It is important to appreciate that the ECU is constantly testingfor an improvement in fuel if there is no knock detected when operating above theOCTANE UPDATE THRESHOLD, by increasing the octane number and trying to runfully on the HI-OCTANE map. Thus, for a stock un-tuned EvoX or RALLIART, using98RON or 93MON fuel, EvoScan should always be reporting some low (1-3) level ofknock.Tuners typically spend the time to chase out the knock so they can get stableoperating conditions and get on with chasing HP with increased boost and othermodifications. Tuners report good results when using E85 and re-tuning the ECUand injectors to suite.When you start using E85 or similar ethanol fuels, or when using meth-waterinjection, the spark map tuning gets a whole lot harder and you can no longer relyon the knock sensor to give you the definitive answer as to how much timing is toomuch. E85 for example can accept spark advance that would show massive knockon regular fuel, with no evident knock, yet your rod bearings are being hammeredto death.An important additional feature to these ECUs, not previously used, are sparkadvance upper and lower limiting maps. Note that the upper limit map needs tohave values higher than your HI-OCTANE SPARK MAP.Figure 22:IGNITION TUNING – stock RALLIART SPARK ADVANCE UPPER BOUND MAPREV: 0.K merlin@three.com.au Page 47 of 134