Thoughts on VANOS and (Lean?) Spool Strategy

[Jeffman]

Logged my VANOS functioning today. Here are the logs showing VANOS in/exh x actual/requested. No VANOS codes since I cleaned and switched the solenoids. But based on the logs do my VANOS solenoids seem reasonably happy, or slightly tired?
http://datazap.me/u/jeffman/85f-wgdc-22-vanos?log=1&data=2-14-27-28-29-30&solo=27-28-29-30

 

[RSL]

Logged my VANOS functioning today. Here are the logs showing VANOS in/exh x actual/requested. No VANOS codes since I cleaned and switched the solenoids. But based on the logs do my VANOS solenoids seem reasonably happy, or slightly tired?
http://datazap.me/u/jeffman/85f-wgdc-22-vanos?log=1&data=2-14-27-28-29-30&solo=27-28-29-30

I haven't logged VANOS request in a long time, but I wouldn't be too concerned about a few degrees difference. 76k on mine without issue yet. Since you cleaned and swapped them, might want to reset VANOS adaptations though if you haven't and see if anything changes. You should really plot that boost curve on a compressor map lol

 

[Jeffman]

Lol. Here you go...we are super-efficient then go off the charts, baby!

 

[RSL]

Mine was further left even, using 95% VE assumption, barely hanging on the 65/70% island iso and using manifold pressure. Should really add a couple psi for actual turbo outlet pressure. Either way, think it's safe to say you're using it all and then some

 

[Aaron]

We are no where close to 95% VE. It is commonly held that 100hp/L N/A is 100% VE, so the S54, S63, etc. Without the fans, our motors would not even make N52 numbers, I'd guess around 200-210hp. We're not even close to 95% VE, we don't have the head or cams for that.

 

[Jeffman]

Interesting. Do you know who, if anyone, is working to modify the N54 head and cams? Maybe VAC in Philly?
In the meantime my stockers keep spooling up to 25 psi then decrease to 15 psi redline...and when they fail it'll be time to upgrade.

 

[Aaron]

There is a company making cams now, I know VTT has a set. They're seriously expensive, I think on the order of 3,000-4,000 per set.

MMP and VAC Motorsports are both doing cylinder heads, and getting some fairly substantial gains with them. But, like most flow related modifications, they aren't going to do much good off boost, and may even hurt turbo spool and response. But once the turbo comes on, you'll make a lot more power with less boost.

 

[RSL]

We are no where close to 95% VE. It is commonly held that 100hp/L N/A is 100% VE, so the S54, S63, etc. Without the fans, our motors would not even make N52 numbers, I'd guess around 200-210hp. We're not even close to 95% VE, we don't have the head or cams for that.

My point was, assumed VE and/or PR would have to be even more optimistic for his graph to be even further to the right of mine. If his turbos are holding together, isn't hitting choke and IC isn't on fire, it's just a line on a paper.

I thought Schrick released a limited quantity of cams not long ago for $1500.

 

[Aaron]

If I remember right, that price was for each individual cam, not the set, which is outrageous.

I thought Schrick released a limited quantity of cams not long ago for $1500.

 

[RSL]

If I remember right, that price was for each individual cam, not the set, which is outrageous.

Yikes. Yeah, that seems a bit ridiculous.

 

[all4bspinnin]

shcrick and cat cams have n54 stuff

 

[all4bspinnin]

Thanks for all the help. Just finished rpm×setpoint table. Gonna go datalog

How did it go?

I was telling a coworker that I trust to watch his logs/data about the rpmxsp boost control. He begged me to set him up. We went and made a few logs and his boost is solid as a rock. perfect plateu with a small taper up top like i set it. its sneaky sauce for sure.

 

[Idahospool]

So far so good, adding in more wgdc. Ive noticed in several tunes from different people that actual load is usually 10% or so lower then target. Cant say ive seen a tune where is dead on. Ive been keeping actual close to target load but the second it gets to close i get throttle closures. Is this the reason for the gap between the two?

 

[Jeffman]

Hey Idaho,
That's exactly my experience - maximum Actual Load is about 10 units lower than Requested Load. And it's closer in cooler weather. I'm sure Jake knows the exact reason. I think throttle closures are due to DME sensing an overboost when your wgdc gets too high. Did you get any codes?

 

[all4bspinnin]

Just curious, mind posting your p factor? Ive seen situations where if your p factor is set really low, it will max out and maintain a set distance between load req/ load target

 

[Idahospool]

@Jeffman i noticed a table in ur bin, that i cant remember the name of right now, but it was like a max percentage of load or boost and yours were lower then mine. Im gonna mess with it tonight and see if that changes the difference beteeen target and actual. My first tune was too high in places and gave me throttle closures. But im targeting 180 load and can stay within a couple points of target. I was just wondering if people were keeping actual below target to prevent closures when there were small overboost oscillations

 

[Idahospool]

@all4bspinnin my p factor?

 

[all4bspinnin]

@all4bspinnin my p factor?

The P factor table from your boost control. that probably isnt the issue though. i was just thinking out loud basically.

 

[Idahospool]

@all4bspinnin, was just making sure u were talking to me. Ill post it once i get my kids to bed but i think its still stock. @Jeffman was nice enough to send me his bin so i could check it out. Our p factors are very different but i didnt want to just copy it as i wouldnt learn anything that way

 

[RSL]

Cant say ive seen a tune where is dead on. Ive been keeping actual close to target load but the second it gets to close i get throttle closures. Is this the reason for the gap between the two?

i noticed a table in ur bin, that i cant remember the name of right now, but it was like a max percentage of load or boost and yours were lower then mine. Im gonna mess with it tonight and see if that changes the difference beteeen target and actual.

Look at just about any OTS MHD log. Yes and no on the distance between them, but almost no point in running them on top of each other unless you have to.

If you're talking about the Boost Request Offset % table, lower values push boost target or set point. It was used for spool mode initially, but lower values were just copied to the entire table at some point and that has been perpetuated by many since. It impacts a lot of other things though since it's essentially a VE table. If you lower it significantly anywhere, keep an eye on things, especially your fuel trims.

Hey Idaho,
That's exactly my experience - maximum Actual Load is about 10 units lower than Requested Load. And it's closer in cooler weather. I'm sure Jake knows the exact reason. I think throttle closures are due to DME sensing an overboost when your wgdc gets too high. Did you get any codes?

I don't know if the set point logic does anything differently, but there is no shortage of things that impact actual load and a combination of things determine the request/actual load relationship.

Where you're both seeing throttle closures, but actual load is below requested load, look at your boost mean compared to boost target. I'll almost guarantee mean is over it. You can dial down closures, but as all4bspinnin alluded to, PID tuning determines reactions for deviation (error) size from target...both under and over.