Guest |99| Posted March 11, 2009 Report Share Posted March 11, 2009 I currently have the 'Master' fuel set at 19mSec and have mapped the full engine range. With this setting I get a range in the fuel table values of 28 ->42. If I change the master setting in order to get a greater range in the fuel map numbers is it necessary to completely remap the fuel table or can the fuel table be 'scaled'?? Thanks Quote Link to comment Share on other sites More sharing options...
rayhall Posted March 11, 2009 Report Share Posted March 11, 2009 Any change to the Master will mean you need to retune. If you want to make a small change to the whole table, using the Master is not suitable, as is very course. To make fine adjustments to the whole fuel table do this. Right click on the fuel table and select Entire Table Change -> Percentage. This will let you trim the whole table. Ray. Quote Link to comment Share on other sites More sharing options...
Guest |99| Posted March 12, 2009 Report Share Posted March 12, 2009 Hi Ray, I have tried the % change and rather than changing by the %age of the table value (ie -10% of 30 = 27) it tends to change the fuel table by the value of change (ie -10% of 30 = 20)?? Quote Link to comment Share on other sites More sharing options...
rayhall Posted March 12, 2009 Report Share Posted March 12, 2009 I just tested the percentage change and it gives the correct values when using + or - percentage. If I have 45.4 in the cells and add 10% it changes to 49.9 If I have 45.4 in the cells and subtract 10% it changes to 40.9 Ray. Quote Link to comment Share on other sites More sharing options...
Guest |99| Posted March 12, 2009 Report Share Posted March 12, 2009 Hi Ray, I found out what is happening. When the change box comes up it is necessary to include the '%' in the change box otherwise it just changes by the number. I made the mistake if selecting the whole box and not including the % at the end of the number (it must be included). Quote Link to comment Share on other sites More sharing options...
Guest |99| Posted March 12, 2009 Report Share Posted March 12, 2009 Hi again, I just tried the same deal with the 'offset' and if you include a % at the end then the offset will change by the %. It seems that "offset" and "percent" will do the same thing depending on the % at the end of the input box. Quote Link to comment Share on other sites More sharing options...
Guest |59| Posted March 12, 2009 Report Share Posted March 12, 2009 It would be nice to change the master scaling without affecting the tune. It will be useful for an injector change without retuning the whole map. It will also be useful for a new installation too. One can do the idle and part throttle fueling first and then have the engine run-in. During full throttle tuning later, one may find that the tables values are too low or too high. One can then just use the master scaling to correct this without needing to re-do the idle and part throttle fueling. Quote Link to comment Share on other sites More sharing options...
rayhall Posted March 12, 2009 Report Share Posted March 12, 2009 It would be nice to change the master scaling without affecting the tune. If you make changes to the master value the injectors will inject more fuel in relation to the values in the table. The master is not there to automatically change the values in the fuel table. It will be useful for an injector change without retuning the whole map. You can do this now. The fuel table trim mention above does this. You would still have to make tuning adjustments as injector flow in relation to pulse width are not the same for all injectors. It will also be useful for a new installation too. One can do the idle and part throttle fueling first and then have the engine run-in. During full throttle tuning later, one may find that the tables values are too low or too high. One can then just use the master scaling to correct this without needing to re-do the idle and part throttle fueling. If you start with values around 20 to 30 in the fuel table cells and then adjust the master so the engine starts, you will not run out of range. With the Autronic ECU you have used in the past, the table has a range of 0 to 200. It was common to start with 50 in the table. This is 1/4 of the range. The Vipec has a 0 to 100 range. So if you start with 25 (1/4 of 100) you will have no problems. Ray. Quote Link to comment Share on other sites More sharing options...
Guest |296| Posted March 12, 2009 Report Share Posted March 12, 2009 Hi Tinker, The fuel equation in the Vipec is something like this ((fuelmapvalue/100)*masterfuel*multiplycorrections)+additivecorrections Since the additive corrections are the injector volt comp ,idle fuel trims and start prime you can easily rescale the map without needing retuning. So you can half your master fuel and double the fuel map number your tune should be ok. Regards Quote Link to comment Share on other sites More sharing options...
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