Why are most professional "tuners" doing Flex Fuel timing wrong?

[Lakegoat]

Now that you mentioned negative 2's, how do you get the Flex Spark table to accept negative numbers. Everytime I try, it goes back to zero. I even tried to drag the 2d table.

[sevinn]

Now that you mentioned negative 2's, how do you get the Flex Spark table to accept negative numbers. Everytime I try, it goes back to zero. I even tried to drag the 2d table.

I haven't seen this. I just checked several e38 and e67 calibrations that I have on my computer and I'm able to put negatives in 12661, 12635, and 12678. Wonder if it's an e40 thing?

[GHuggins]

The editor won't physically let you enter in negative numbers - you have to highlight the cells or the whole table then go up to the editor box, enter (-2) and then hit the equals icon... You can also put in something like (-.5) and hit the + button to edit individual cells throughout the table... Or just have some tables to copy and paste into the table already made up and then modify them as you go for that particular application...

[sevinn]

I was only trying with the editor box so that explains it nevermind.

[John_C]

Don't know if anyone knows for sure, but leaving the flex fuel spark adder table zeroes or negative 2s should work to the point of not causing other problems.

Guess I'll leave it at 0 until I know for sure how it'll effect things....

[Lakegoat]

The editor won't physically let you enter in negative numbers - you have to highlight the cells or the whole table then go up to the editor box, enter (-2) and then hit the equals icon... You can also put in something like (-.5) and hit the + button to edit individual cells throughout the table... Or just have some tables to copy and paste into the table already made up and then modify them as you go for that particular application...

That still doesn't work for me on the Flex Spark table. Works fine on the high octane table. I can go to 3d view and try to move the lines negative, and it pops right back. LOL

[GHuggins]

Maybe ask hpt - I opened several tunes and finally found an E40 and the E40 was the only one not taking negative values in the flex spark table... That's odd...

[Lakegoat]

I will ask. Thanks for checking. I had almost forgot about that little bug.

[Rtex15]

Alot of good information here..i just started tuning e 85.. now the way im doing it..correct me if im wrong..but with 93oct at afr 12.5 to 12.8 adjusting main spark table i can get between 21 to 22 degrees advance timing..now with e 85 with ethanol percentage at 77% at 9.0 to 9.2 afr..i can set the flex fuel table to add 10 to 12 degrees add wide open throttle wich puts me at between 31 to 33 degrees total of advance timing at wot..and thats reading it on the scanner..now ive ran into were the ethanol percentage has read 62% with some 93 been mixed and with out moving timing it will adjust it self putting out total timing around 26degrees wich is understandable ..with no knocks across the board..u can really feel the power difrence on e 85 as soon as u get to the 29 advance timing and more..my question is am i pushing the engine to the limit by getting 31 to 33 degrees with e 85 am i still safe even if i have no knocks? now all the vehicles ive done have been silverados and sierras and suv if that makes a difrence on weight wise..any advise would be grate thanks

[Rtex15]

Forgot to mention..these are truck 2014 to 2016 lt engines ^^

[07GTS]

31-33 is a bit id want to confirm it on a dyno to make sure it needs that much, with e85 it may not show any knock so it could be making same power or more with less timing, best to adjust timing on dyno to peak hp/torque

[jsbaugh]

10 degrees more timing is a lot even for E85. You need to watch out because its hard to get knock with E85 and you can damage the motor even with showing no knock.