1 BAR SD - High/Low Octane Spark

[XDR]

So if the PCM reverts back to Low Octane map when the MAF is set to fail, why is there a High map? Or does this OS not need the MAF set to fail?

[Dr. Nopps]

Correct the custom "*BAR Speed Density" OS's that you would have to Write Entire onto most of the V8 PCM's don't require you to fail the MAF, they just properly run in SD. So you get both a low & high octane table integrated into the custom OS that would normally be disabled if you just force a Stock GM tune to run in SD.

[ElecTech]

Correct the custom "*BAR Speed Density" OS's that you would have to Write Entire onto most of the V8 PCM's don't require you to fail the MAF, they just properly run in SD. So you get both a low & high octane table integrated into the custom OS that would normally be disabled if you just force a Stock GM tune to run in SD.

You still have to fail the MAF to run SD with the custom OS, but it does allow for the octane learn down functions as you described.

[rs2112]

You still have to fail the MAF to run SD with the custom OS, but it does allow for the octane learn down functions as you described.

I have just installed the 2bar OS in a 2000 Chevy truck. Are you saying I will need too fail the MAF and it not already failed? I have copied my high octane to my low octane from previous work. So I should put my low table back to start? I would really like to have a copy of someones 110 and up VE tables so I would feel safer tunning in these cells as its hard to hit the with normal driving. Trying to make an injector decision and throw the add on whipple ecm in the trash. I do not mind advice in all areas as am new to this. Thanks

[mowton]

Copy your 105 kpa cells and paste them to the 175kPa (or what ever is the last column, multiply this column by 1.5 and interpolate across the 105 to 175 columns. This will be a good starting position for your boosted area.

Yes need to fail the MAF as well as set DTC p0101 - p0103 to fail on first error. I leave the SES checked so I know it has failed over to SD. You can uncheck or set to No Mil when tuning is complete. This Custome OS does give you back the lo octane table feature so multiply it by say .8/,85 to lower them.

Ed M

[schpenxel]

Agree... you HAVE to fail the MAF.

SD OS's will work just fine with the MAF still installed. You can even run them MAF only if you want.. so you have to disable the MAF if you don't want it operational.