I just got my LPE 100mm maf and my HPtuners will be here next monday. Why it takes 10 days to get here is beyond me. Anyway, I'm currently running a 2bar SD tune. Once I get the software, what do I do to convert back to maf tuning?

will I need a 1 bar map sensor?

 

you can run 2-bar MAF enabled. You will have to change the MAF fail hz and copy the LPE MAF tables...there is probably a few things I am forgetting.

 

 

Keep the 2 bar. Its lets you "see" boost. ALso after resetting the MAF fail hertz i would re enable the codes so they can be thrown if needed. Right now they are problly set to non emissions. I dont know about on the LPE MAf tho...

 

I agree, just keep the 2 bar and run the maf with it.

 

Will do. Right now the codes are disabled. I do not have my rear O2 sensors turned on right now either. In fact, I don't even have any. Does that matter?

The reason I am going back to a maf is because the local tuner who I plan to use won't tune SD because he doesn't have any experience with it and he thinks it's just a bad idea in New England with our constant weather changes.

I need to get the truck to a tuner soon to fix my surging idle/stalling issue which started after the trans/converter install.

 

You can tune for climate changes with 2 bar, it's not difficult. Sounds like your tuner is not that experienced. Might be better off looking for a new tuner instead of a new MAF. The problem with going back to a MAF setup is that regardless of the physical size or flow capacity of the MAF, your PCM is still limited to a max of 512 g/sec airfllow through the MAF. The MAF itself may be able to read higher, but the PCM has hard coded limits on how much it will recognize.

 

Look at the table values BC posted. Notice how they all flat line at 511.99? That is the PCM limit Thunder is referring to. Once you reach that point your base fueling flatlines and any additional fueling has to be commanded by the PE table. Therefor, imo, it is probably less accurate than a properly tuned VE table in SD even during weather changes. I am not currently running SD as I dont have a 2-bar map but I did run SD when I had the H/C LS1 in the truck. By monitoring the afr via the permanently mounted wideband I never saw more than a .2-.3 swing year round. Although the climate here may have less drastic change than in the NE.

 

I know at least for efilive there is a IAT multiplier that compensates for temp changes when using SD. And without o2 sensors you can still run MAF 2 bar. You just wont have the option of going closed loop, so after you max runs out your pretty well back to were you started. I would run 2 bar CLSD, or even OLSD like i said multiplier compenaste for temperature when set up right.

 

Until you max out the MAF, won't the fueling be more accurate than an SD tune that isn't absolutely perfect? And give better around-town throttle response? And Dan, did you remove your O2 sensors as charcold-bowtie is implying? Does it seem like I just learned how to use the question mark?