EtchyLives

iTrader: (1)

Got a few questions about the AVC-R that maybe you can answer. Let me explain my situation:

My primary problem is overboost. My target is 1.1bar and I'm spiking at some points as high as 1.34 according to the AVC-R.

After a little experimentation, I figured out that setting the Duty Cycle to 70% was causing the really high boost readings. After returning the duty cycle to 50% and the boost level to stock (0.95bar) it was running normally and peaking right at 0.95 or 0.96. Anytime I turn the boost target up to 1.1bar I start getting spikes up to 1.18bar.

I currently have gear learning turned on, and I have watched the boost spike at each of the NE points (3000-7000 every 500RPM). After driving awhile, I check the duty solenoid levels, and they've reset themselves to other than flat (usually 62% through 4000RPM and then dropping to 60% for the rest of the band).

What I'm looking for is pretty constant boost with minimal spiking (.01-.03bar is OK). Currently, to avoid serious overboost I've reset my boost level to 1.05.

Also, I tried setting a boost curve and that resulted in levels up near my current 1.17bar.

Thanks for your help in advance.
-Greg

EtchyLives

iTrader: (1)

TTT

teiva-boy

To be honest I can't remember a damn thing about the AVCR, my head is filled with wastegate sens, wastegate level, boost level and more.... The LINK sucks

I'd have to sit behind your wheel to remember what I used to get solid boost.

Rexstang

iTrader: (1)

Greg,

Don't confuse duty cycle with constant boost. The short of it is that: The duty cycle should be higher in the beginning to get boost to your desired level as quickly as possible. Then the duty cycle will drop slightly to maintain your target boost level and avoid spiking. If you had a constant duty cylcle throughout your rpm band, boost wouldn't be building as quickly as it could at low rpms.
Also, you will have some minor spiking if your aggressive with building boost, its just gonna happen. You just don't want any major spikes like .2 bar over your setting.
As a rule of thumb, I'd set my boost at 1.0 bar and duty cycle at 55%. I then go beat the crap out of the car until the controller learns my duty cycle settings. Then if I want to increase or decrease boost, I just change the desired boost setting. I've found that the 55% duty cycle is a good balance between building boost quickly and avoiding spikes. Like I said you should get some minor spiking due to just having an aggressive setting just like you found out though too aggressive a duty cycle setting will give you some serious spikes.
Remember don't confuse constant duty cycle with constant boost levels. Good luck.

Jayson

EtchyLives

iTrader: (1)

Thanks Jayson,

That is essentially what I did. Right now I'm getting 1.08bar at a 1.05 setting and the duty cycle is learning rather well. This is fine for me, and I think at the track I'll push it up to 1.1bar. Do you have gear learn on (0) or off (X)? Currently mine is on but I think I remember a post with you and mitch turning it off. Either that or I'm all f'd up in the head.
-Greg

DaveWRX

Could be, or youre hitting the booze again...

Rexstang

iTrader: (1)

Once I was happy with the setting I turned off the learning and then reduced the feedback.

EtchyLives

iTrader: (1)

cool, thanks. Just gotta get more high rev gear pulls before I call it quits. All freeway driving makes it hard to get high revs... even 3rd gear puts me a tad over the legal limit.