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I forgot: Is Giac tuning out the rear O2 sensor on the PC16 file?
If not: what is needed to get rid of the code when installing 3" downpipe?
 

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I'm running the GIAC PC16 file and a test pipe. I had to put a spacer on the second O2 sensor to get rid of "CAT below efficiency" codes. I went with the 42 Draft Designs spacer. O2 Sensor Spacer

On my truck (someone stole the CAT) I went with two spark plug anti-foulers ($6). But I have more room to fit that under the truck. I'm not sure if there is clearance for that on a Passat. Measure and see.
 

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Wish they would just tune it out. But IIRC, we used defoulers also on our A4 PC16.
Regarding the dyno jet: Dynojet is notorious for inflated numbers. The 209 wHP shown would equate to 280 cHP at 25% drivetrain loss.
What are realistic numbers? 230-250 cHP?
The MAF pegs out around 185 g/sec (should be close to 5V then). Since MAF logging is readily available for the AEB (but not much more): what are the reported MAF numbers with the PC16?
 

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RPM = 5440
injector average time (ms) = 16.32
Mass airflow g/s = 184.86

From a log I did some time ago. I've made some changes since. Haven't logged any data recently.
 

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Wish they would just tune it out. But IIRC, we used defoulers also on our A4 PC16.
Regarding the dyno jet: Dynojet is notorious for inflated numbers. The 209 wHP shown would equate to 280 cHP at 25% drivetrain loss.
What are realistic numbers? 230-250 cHP?
The MAF pegs out around 185 g/sec (should be close to 5V then). Since MAF logging is readily available for the AEB (but not much more): what are the reported MAF numbers with the PC16?
Driveline loss on these cars isn't near 25%, closer to 10-15% which would be about 230-240 CHP if it was 200 FWHP, so the numbers are about right on the original dyno
 

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Giac PC16 - MAF limited - need a bit more flow

The block of info quoted is not J31 info, it's the newer "hammer" file info for the ecus after the '00 J31 file. The J31 file and later years are not compatible because the eprom is not compatible, 2x the storage size in the later ecus.

On the fuel trims, it's not a matter of freaking out or not, it's just that the trims are set during all your regular driving conditions and things are running just fine based on that trim, say -10%. Then you go WOT and the maps call for x fuel and you get 90% of x. This may not be good under WOT. Just because the ecu maps tended toward rich in normal driving, doesn't mean you're still rich by the same amount WOT. You want the car to run as close to the program maps as possible under WOT and it wasn't programmed to run -10%. The rest of the time I'd agree the trims can adjust for just about anything.
I know its a stone old post, but so is the PC16 file.

I am pushing (VAGcom) 193 g/sec (custom K04, 315cc, AFPR) and are afraid I am maxing out the stock MAF.

a) how can I tell if the MAF is maxed out?

If maxed out (and assuming the turbo could provide more flow), how can I get around the MAF limit?
I have a VR6 housing (I think they are 36% larger. This would mean for the same output voltage (to ECU), there is 36% more air mass.

b) to bring the air mass and fuel amount inline again, can I increase the fuel pressure to get get 36% more flow (nominally, that would require 1.36x1.36=1.85 times the fuel injector pressure)

c) to bring the air mass and fuel amount inline again, can I install 36% larger injectors?

I want to CAREFULLY try the larger MAF housing. Crank up the fuel pressure (I know I need more fuel), idle first, then part throttle, no boost.
What values/blocks should I log and keep an eye on with VAGcom?
 

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vtraudt, your best bet is to get a wide band air/fuel ratio gauge. (MTX-L Wideband O2 Digital Air/fuel Ratio Gauge) The narrow band O2 sensor on the AEB setup is only capable of measuring a/f ratios close to stoichiometric (14.7). With the right gauge giving you the feedback you need, you'll be able to tune the WOT fueling (injector size & fuel pressure). As it is, you have no way of knowing if you are going rich or lean at WOT boosting.

At 193 g/s you are maxing out the stock AEB MAF.
 
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