MAP or MAF for timing

[Dave Lewis]

Does the Duramax use the MAF or MAP for timing? Looking at B0901 on my stock tune it is set to MAP. I would have thought it should be using MAF. Please forgive my ignorance.

[GMPX]

Dave, all the GM files I've seen are using MAP (actually Baro), reason?, not sure.
You can confirm this by the fact the A,B,C load points for the MAF are all set to 32 as well as the MAP selection.

Well, thinking about it, if set to Baro that gives you 3 timing tables to compensate for Baro differences, but if you set it to MAF you could have 3 timing tables based on load.....that to me sounds like a much better option as far as when these engines are being pushed way above the power levels GM would have tuned for, the only problem is you then loose Baro timing compensation because there is no Baro based timing table.
That might very well be an issue for someone who lives up in the clouds.

Cheers,
Ross

[GMC-2002-Dmax]

Use Injection Timing MAP "C" as it is in effect above 162 degrees.

The other MAPS "A" and "B" are used for lower temps and then use multipliers for BARO and Fuel Temp to further alter timing if necessary.....but the multipliers do not effect anything over 132 degrees and the factor is ZERO so it does not effect timing anymore.

If it rattles you have too much timing..........or you might want to move pilot timing closer to main injection timing..........use PILOT Timing table "C" for 155 degress to 162 degrees and "D" for 162 degrees and over.......

You would be surprised how different the truck reacts and the motor reacts to pilot timing........

If you need any help you have my email and you can PM me,

T NY

[Dave Lewis]

Awesome, Thanks. Now if it would quit snowing.

[GMPX]

You would be surprised how different the truck reacts and the motor reacts to pilot timing........

You mean, you can make it sound like a Powerstroke

Cheers,
Ross

[dfe1]

You mean, you can make it sound like a Powerstroke

Cheers,
Ross

That's "Powersmoke"

[Max Power]

You mean "PowderStroke"

[GMPX]

"Powerjoke", keep em coming, where a happy GM family around here

Cheers,
Ross

[Max Power]

Hey did you hear Ford found the problem? Yep, they even circled it!

[joecar]

Found On Road, Dead.