Maxing the MAF out, with boost cars I dont have much problem jacking up the PE table to compensate.

Cant do this with this setup, so I need to move this table up. Anyone have a curve to fit a stock MAF? or just apply a logarithmic fit curve?

Which would give me more room to breathe with the MAF, tell it it has bigger MAF and injectors, or smaller MAF and injectors?

 

Ud Luze

 

Boosted guys run into 2 problems with the MAF. One is maxing the MAF itself out (so it's reading its 12000Hz). That can be solved by getting a larger or recalibrated MAF. The other problem is the limit on the value for airflow the pcm can process, which I think is 511 g/s depending on the year of the pcm. One way to over come this is cutting your MAF table, injector tables, ve tables, etc in half (or whatever fraction you want I suppose). The other way would be to change your pcm operating system to get rid of the 511 g/s limit. Maybe soon we will be able to mess with our own operating systems.

 

Also dont forget the MAP sensor. It only reads one bar. HPTuners new software will allow for a 2 bar map so a SD tune without the maf will be possible unless you are running a dry shot

 

Humpin, do you know if the new software will allow for the 2 bar by changing the OS, or just by scaling all the tables? If it does change the OS, do you keep the same MAP resolution in all your tables?

 

the new software is propreietry(sp) and it alters the os and adds resolution to the tables for use with a new 2 bar map

 

Dry shot OWNS YOU

 

Yeah the aussie guys have been running 2 bar stuff on stock pcm for a couple years

 

Here's a link to something i was testing today:

http://www.hptuners.com/forum/YaBB.p...num=1103180232

As for the MAF, extending the table is not really required, easier to get a MAF that flows more air for the same freq range and then recal the curve. The bigger issue is the 512 g/sec airflow limit (airflow is stored in the PCM as a 16bit value, of which 7 bits are used for the decimal. ie. Airflow is stored as Airflow g/sec x 128 and 512 x 128 = 65536), rescaling that is a big job. As some have done you can run 2 MAFs with a black box that avergaes the two (or i guess you could just read one MAF signal) then halve your injector flow rates across the board. Either way you got to keep in mind what tricks you are playing when you tune.

 

Yawn. I think everybody else will wake up and read this stuff later. I was checking that MAP thing out a little while ago. Pretty neat.