Initial Details into How The Boost Based Tuning Works with AccessTUNER

[Dano]

Originally Posted by 08_ms3_gt i've been experiencing this. first cold weather with fuel pump and downpipe --> running WOT gave me AFR's around 12.2 when commanded AFR is 11.5. i may work on fracking around with it (Dano, you've done this?), but for now i flashed a 1.06 map in the hope that it'll keep my AFR's healthy.

Forzda's right and your MAF could just be off, just use your actual AFRs to re-calibrate your maf in the voltage ranges you are lean. get logs with Maf vt and AFR ...its fairly easy to change the % of your MAF UP to meet your fueling targets. you prob don't have to change your entire MAF curve just the upper ranges and smooth out the transitions.

now if you were logging CDFP and you were dropping down to 1200PSI then you have pump issues otherwise its MAF.

[08_ms3_gt]

Originally Posted by Dano2010 Forzda's right and your MAF could just be off, just use your actual AFRs to re-calibrate your maf in the voltage ranges you are lean. get logs with Maf vt and AFR ...its fairly easy to change the % of your MAF UP to meet your fueling targets. you prob don't have to change your entire MAF curve just the upper ranges and smooth out the transitions. now if you were logging CDFP and you were dropping down to 1200PSI then you have pump issues otherwise its MAF.

thanks for the insight. the 1.06 map gives me the target AFR, but i would assume i could adjust my MAF table with a 1.07 map to hit my AFR's, run w/o load cap, and get more power...? i'll have to try this sometime soon, not yet b/c i'm getting totally hammered @ work :\

funny story with the CDFP - just replaced mine b/c the old one was dropping below 1000 psi (?!!?!) at WOT. warranty replacement on a PTP pump. new one's holding 1600+ psi at WOT. the funny part is that i was hitting target AFR's w/ the old pump for some reason. i'm guessing i was down on power, though, if the ECU was cutting throttle due to the pressure drop. now, with the new pump, my pressure is fine but my AFR's are lean. can anyone explain that? weird shit.

[Dano]

just copy/paste the good MAF cal into your other map...5 minutes and you are gold.

[08_ms3_gt]

Originally Posted by Dano2010 just copy/paste the good MAF cal into your other map...5 minutes and you are gold.

really? i didn't even do a MAF cal.

both maps are OTS Stage 2 SF w/ TMIC. just 1.06 versus 1.07. i have a Cobb STS, downpipe, and ETS TMIC (and other stuff).

i figured the MAF tables were the same for both. maybe not?

the only other potential consideration is that i didn't give either map a full 100 miles to break in - i rolled on it WOT at about 50 miles for each map, and the results were 11.4 AFR's (target) for the 1.06 and 12.2 for 1.07. i tried putting a few more miles on 1.07 and cycling the key a few times (results did not change) before switching to 1.06 to see if there was a difference.

i could do a MAF cal for 1.07, assuming the tables are identical. i would have to check them to see, obviously. i have been avoiding tuning bc RealGib told me his blown engine story (we talked @ some g2g's) which kinda freaked me out. altho his was from FFS iirc.

[Dano]

hum..you could just compare the two by pasting the 107 map MAF A or B into the 106 MAF B table and switch back and forth looking at the graph to see if there is any difference. If there is then you know Cobb made a change in the MAF and you should start with the one that is closest.

At any rate, if you haven't done a real MAF calibration, that is the place to start with any tuning.

PM me if you have any more ??

[Christian.]

Please allow or use the AutoUpdater function to get the newly updated Ign Table - Max A-B tables.

Christian.

[Dano]

Ok,

I am just getting around to actually trying the boost based logic and notice something quite different in the Boost Dynamics table vs the Load Dynamics.

LD has way more fine grained resolution than BD tables...what gives? I can adjust load error into the 100ths by 100ths but BD error is in 2PSI increments. how would you ever need 7 to 9PSI of over boost or under boost error control?

The reason I ask is because I am trying to fine tune BD table values to match up to my GT28 spool charastics and the res is so low.

I must be missing something...plese give me a clue

[Dano]

I have been load tuning...well for over a year now and each tune took me...like 20 map revisions to get load/boost dialed in.

Switched to boost tuning a day or so ago and by rev 5 I have the tune completed with regard to boost targets.

The car isn't as "twitchy" as it was with load tuning and it is actually tamer in the lower gears than with load tuning. Boost comes on much smoother than if you load target. Load targeting is of course more difficult as you need to scale load up to match the spool characteristics of the turbo or occiliation is a bigger issue. Targeting boost is much easier.

After I got my WGDC tables re-calibrated, there was no need to even touch the Boost Dynamics tables.

I will now move on to the Boost Comp tables to see if I can limit boost per gear.


Suffice to say boost tuning is 100x better so far.