Exponent Posted March 20, 2013 Report Share Posted March 20, 2013 hello i tried to calculate a master fuel for the basic fuel. so for a 1000ccm injector (1 injector per port) and 3.6l 6 cyl engine i calculated for 100kpa and 100% ve a maste pulse width of 3.9. Makes that any sence? How do you figure out your master quantity? BR Phil Quote Link to comment Share on other sites More sharing options...
Levon Luther Posted March 21, 2013 Report Share Posted March 21, 2013 What injectors? Bosch ID1000s? This is the totally wrong way to do it im sure, but I have ID2000s and used a master of 7ms and 5% (7.35ms) trim on a 2.5 liter 4cylusing 48PSI (330kPa) base pressure That is .625L per cylinder. You are at .6 liter per cylinder I would say that for you, using a 3ms master with 20% (3.6ms)Â Trim would be close. Smarter people will comment after me, but if you are just looking to see if you can get it to idle, try that. If you want to play it safe, bump up the fuel a little bit. Better yet, talk to your tuner. Quote Link to comment Share on other sites More sharing options...
Exponent Posted March 21, 2013 Author Report Share Posted March 21, 2013 I am using this injector on pump gas. http://www.witchhunter.com/flowdatapix/b0280158040.jpg I am wondering why I cannot find a master calculation form somewhere - it should be just physics when i get it right? Quote Link to comment Share on other sites More sharing options...
Scott Posted March 22, 2013 Report Share Posted March 22, 2013 Hi Philipp, The calculation for working out a master fuel number would be possible, but complex. As Levon and yourself noted, factors to include in the calculation would include: Fuel Pressure Cylinder Volume Injector flow rate Atmospheric Pressure Engine Volumetric Efficiency Density and temperature of the air Required Inj PW Most tuners know from experience on similar setups what a suitable master fuel number is. You are better to start with a number that is too high than too low. Using a wide-band oxygen sensor and monitoring the AFR while you make adjustments would be a good start. The aim is to have middle values in your fuel table with a value of 50. Scott Quote Link to comment Share on other sites More sharing options...
Exponent Posted March 22, 2013 Author Report Share Posted March 22, 2013 yeah - i will start with the M50b25 base map and a master fuel of 4 (my engine config 1000 injectors and 3.6L) Then I will try to adjust the fuel map via TPS sensor and no boost and then go to the 4d fuel  table and adjust the fuel and ignition with the map signal. which maximum ignition angle would you recommend to start with to be safe even with 1.5bar? 20°? BR Phil Quote Link to comment Share on other sites More sharing options...
Chris Forbes Posted March 23, 2013 Report Share Posted March 23, 2013 I'm having the same issues with a set of ID1000's on a 2JZ, master fuel is set at 4ms and I am getting AFR's of 9's. just about to start on the % adjustment Quote Link to comment Share on other sites More sharing options...
Simon Posted March 25, 2013 Report Share Posted March 25, 2013 Check the dead times have been set as these will have a massive effect at low opening times. Quote Link to comment Share on other sites More sharing options...
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