Target airflow/rev

[boost97gst]

All mods up to date in my profile. As you can see i have crower 272s. This makes it very very difficult to achieve .25 gr/rev. Not happening.
I have stock comression pistons, no boost leaks and im trying to get it around .31 g/rev. Im still having to take my stock deadtime of 400usecs and bump it up to nearly 700 to get combinedft around 0%.
Question is: If i slide my mafcomp up thus increasing my airflow i could possibly decrease my deadtime closer to stock. Can i do this? If i do this what are the negative side effects? Boost not reading right in link? Afrest and actual being off? I might need to see around .35 g/rev to get a manageable deadtime.
Thanks

 

[lil corb]

All mods up to date in my profile. As you can see i have crower 272s. This makes it very very difficult to achieve .25 gr/rev. Not happening.
I have stock comression pistons, no boost leaks and im trying to get it around .31 g/rev. Im still having to take my stock deadtime of 400usecs and bump it up to nearly 700 to get combinedft around 0%.
Question is: If i slide my mafcomp up thus increasing my airflow i could possibly decrease my deadtime closer to stock. Can i do this? If i do this what are the negative side effects? Boost not reading right in link? Afrest and actual being off? I might need to see around .35 g/rev to get a manageable deadtime.
Thanks

You have to a base set up of airflowperrev to a desired limit before messing with deadtime. First make sure all your settings are correct (injector deadtime and global fuel, base fpr, base timing and no boost leaks) Then see where your MAFRAW is at at idle and adjust accordingly. If your airflowperrev is high than .25-.27 and your mafraw at idle is 50hrtz. Adjust the 50 hrts toward a negative number.

Once you get your airflowperrev to a good enough number, then adjust deadtime to get your combined fuel trip to +/- 5%.

Do you have a wideband?

Good info this thread http://www.dsmtuners.com/forums/articles-tuning-ecu/262460-basic-dsmlink-tuning-guide.html

 

[boost97gst]

damn, nice link. Good read. Thing is, i understand that and my mafraw is very near 50hz at idle. If i were to go to .27 id have to pull a good 10 to 12% negative on teh mafcomp and consequently up my deadtime from the stock 400 to near 800usec. This just doesnt seem right. I may follow the method of logging ltft's and doing it that way. Maybe i need to decrease my globals even though i have it set for 940cc just like it says on their website. 1000ccpte;s actually flow 940 so thats what i used as my value to calculate off of.
i thank you for actually responding. Its hard to get people to chime in sometimes on the more complex tuning issues. ill post up a log tomorrow and maybe u can evaluate?
Btw, i have read that with 272s .31 is target airflow/rev, not .27. That actually makes a ton of difference and is the real reason behind this post. I need a clear answer where my airflow should be to dial in everything else obviously

edit: yes, lc1wb and its logged.
edit: i have a 2g cas, no base timing like u 1g guys.