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

MERLINS RALLIART & EVOLUTION-X TUNING GUIDE10.05-INJECTOR TUNING – NEW INJECTOR SETUP METHOD 1This is a method for arriving at good scaling and latency setting in your ECU wheninstalling new injectors, particularly when the injectors are known ie can be foundin the injector table. You will need an air fuel ratio meter for this.1a. For un-documented injectors: Divide the “rated” flow rate by 1.15 as a startingINJECTOR SIZE SCALING value. This should at least be reasonably close. Open thelatency table in EcuFLASH for the stock injectors. Highlight/select all the latencyvalues and increment the whole set until the 14 volt value equals 0.600mS. This ofcourse will not be the correct final set of values, but the general shape of thecompensation curve will be preserved.Or…1b. Find the injector data in the TYPICAL INJECTOR SCALING AND LATENCYPARAMETERS table and set the scaling and latency data into the ECU. This shouldbe reasonably close.2. After saving your current bin file, set all fuel map values 120 and above to 11.5.3. Disable LEAN SPOOL by setting the start rpm to 7500rpm.4. Start the car and allow the engine to reach operating temperature.5. Run the car into some low level of boost ie above load 120. Keep the boost levelsto less than 12 psi preferably. Compare the air fuel ratio reading to the set 11.5value. Use some caution doing this, avoid running too lean. If the AFR reads lean,set the INJECTOR SIZE SCALING value smaller. If the AFR reads rich, set theINJECTOR SIZE SCALING larger. Repeat this until the AFR reads to about ±0.1 ofthe desired 11.5 AFR.6. Re-load your desired or original fuel maps back into the ECU with your newINJECTOR SIZE SCALING value. Reset LEAN SPOOL start rpm to the correct value.7. Log fuel trims at idle for 15-20 minutes. Add the long term fuel trim (LTFT) andthe short term fuel trim (STFT). eg If LTFT =-12.5% and STFT LO = -3.5%, thetotal is -16%. So, shift the whole latency curve down 16% by the highlight anddecrement method described above.8. Log fuel trims at cruise for 20 minutes and then 5 minutes of idle.9. If trims are roughly the same, but positive, then you need to lower your injectorscaling value. If both trims are roughly the same, but negative, then you need toraise your injector scaling number. This adjustment should now be very small.REV: 0.K merlin@three.com.au Page 89 of 134