[crystal_Imprezav]

So I have been working on a new AVCS calibration and today was the first time I got to go out for some test runs. Keep in mind that the only thing that I had changed was the AVCS map during this session. I typically pull any where from a 3.2-3.3 load with a smaller than stock intake calibration to get the car to run a little leaner up top. The weather was about 40-45* which even at that level had never pulled more than a 3.4 load which is my safety column in the fuel and timing maps. And oh yea the clutch was slipping in 4th that was a first. Check out this graph:


Intake Calibration comparison with stock mapping. The higher the number the higher the load and vice versus.

I think I am making some more torquee

[LOLSTi]

Nice DA values... what kinda Ignition Timing values does your graph show up top?

[sti752]

What are your resources as far as your techniques for AVCS tuning? I've seen a thread on Nasioc about it but don't know of much else.

You are running meth injection correct?

Either way that is quite impressive especially w/ your rescaled intake table.

[crystal_Imprezav]

18*@3k; 20*@4k; 22*@5k; 24*@5.6k; 28*@6.4k; 32*@redline. Pretty conservative as I would rather run more boost and a little leaner AFR's. Just goes to show how much AVCS can help the torque curve proof being that the engine load went up at the same boost level, rock steady IA, and a consistent AFR. I have played around with many combinations and this is truly the first one that has produced significant results. I don't wanna spend money on a new clutch to hold the torque monster!?! Oh yea this also helped with the surge I was experiencing in 5th sometimes. Reducing some lower load/rpm during spool to prevent recycling and egr.

[karr1008]

Wow, that's a nice graph. How did you acomplish it? In other words, how did you change the AVCS variables? Is there a way to do it through some AP?

This is quite interesting.

[crystal_Imprezav]

I played around with a lot of calibrations. The thread on Nasioc is actually one of the best ones I have read about. It basically comes down to trial and error to a point to see how the car reacts to AVCS advance relative to getting the calculated engine load and MAF voltage to go up without increasing boost or screwing up your other calibrations. Sure you can get small changes in load like .1 or .2 but I didn't feel that was really gaining VE but maybe some spool which turned out to be the culprit of my 5th gear surge. It likes to spool but not in higher gears and colder weather at low load sites. Another tip is to smooth out the curve. The stock mapping, and OTS Stage2 mapping is very bumpy and non-symmetric. Use a good amount of interpolation and judgment on if it is safe or not. Start out with a safe fuel, boost, and timing map too as it will lean you out some with more advance. As you can see I stopped the AVCS advance right at 4800 which is where it pretty much goes back to the normal load sites I typically see. However I am not a believer of running advance up top like the nasioc craze.

[LOLSTi]

Originally Posted by karr1008

Wow, that's a nice graph. How did you acomplish it? In other words, how did you change the AVCS variables? Is there a way to do it through some AP?

This is quite interesting.

Check which forum you're in.

[crystal_Imprezav]

For comparison previous AVCS calibration with same boost curve (exception of turbo dynamics calibration to stabilize boost with new EBCS), fuel, timing, etc.

[WolfPlayer]

The boost is 1.5-2.0 psi different. It's not really an equal comparison. That is where a lot of the extra load is coming from. It's amazing how much load jumps up when the boost is higher in the midrange. I was hitting 3.61 load today with 21lb of boost in 3rd gear.

It's also important to note that you are running an SMC Alky kit. Although that doesn't apply to the AVCS and load, it's gotta be pointed out. Somebody might see this post and try to duplicate your timing numbers. We want to prevent somebody from doing that ... or else they might get to eat a bowl of rice krispies (snap, crackle, pop).

Not that it matters, but here is my current AVCS: http://www.bescaredracing.com/sti/ec...shots/avcs.JPG

t

[flatthump]

Almost 23 psi at 3070 rpm.....That sounds good to me

Im still learning....I havent had the balls to touch my AVCS tables. Just AFR. DA, and boost.

[crystal_Imprezav]

Originally Posted by WolfPlayer

The boost is 1.5-2.0 psi different. It's not really an equal comparison. That is where a lot of the extra load is coming from. It's amazing how much load jumps up when the boost is higher in the midrange. I was hitting 3.5 load today with 21lb of boost in 3rd gear.

It's also important to note that you are running an SMC Alky kit. Although that doesn't apply to the AVCS and load, it's gotta be pointed out. Somebody might see this post and try to duplicate your timing numbers. We want to prevent somebody from doing that ... or else they might get to eat a bowl of rice krispies (snap, crackle, pop).

Not that it matters, but here is my current AVCS: http://www.bescaredracing.com/sti/ec...shots/avcs.JPG

t

Very true but even if you look at where the boost curve is 23 in one and 22 in another the huge difference in load is definitely due to the AVCS IMO. Another funny characteristic is that your map almost mirrored my previous map which was the one with 21psi. The boost curve on that second graph is wacked out because that was day two of EBCS tuning which was a whole lot of fun in itself to get it to smoothed out and stable like it is now especially when it is cold out like right now (i hate turbo dynamics now). Ive got another log somewhere with similar boost and identical fuel and timing. P.S. Wolf I did a lot of smoothing to the map that looked like yours because down low IMO there is too much advance. I also made the curve more linear in form and where the big power came from was adding 2-6* of more advance in that last column and smoothing/interpolating it down from there but advancing a bit more in the upper loads/rpms. Maybe ill post an image

[crystal_Imprezav]

[WolfPlayer]

Originally Posted by crystal_Imprezav

P.S. Wolf I did a lot of smoothing to the map that looked like yours because down low IMO there is too much advance. I also made the curve more linear in form and where the big power came from was adding 2-6* of more advance in that last column and smoothing/interpolating it down from there but advancing a bit more in the upper loads/rpms. Maybe ill post an image

I thought that I tried something similar - but this may or may not be what you are talking about ...

http://forums.nasioc.com/forums/show...9&postcount=64

Unfortunately, for me, boost was easier attained by running AVCS in the upper RPMs (which shows decreased volumetric efficiency).

An image would help (but, yea, I get it if you don't want to publish your current map ). My car seems to like my current settings but I have no issues with plugging in your map and doing a before and after analysis as long as we agree on what to be looking for (increased load with no boost increase would be my suggestion).

t

[crystal_Imprezav]

Ill send u a PM at some point today. I gotta get some errands done first. By upper loads/rpms I meant at around 2.25 and 3 load and from 3600-4800rpm only. I think that advancing up top past 4800 is as useless and you had previously stated making less VE.

[WolfPlayer]

Originally Posted by crystal_Imprezav

Ill send u a PM at some point today. I gotta get some errands done first. By upper loads/rpms I meant at around 2.25 and 3 load and from 3600-4800rpm only. I think that advancing up top past 4800 is as useless and you had previously stated making less VE.

Understood. I think we might be on the same wavelength. BTW, I updated my post above. I actually hit 3.61 load ... not 3.5 as originally thought. Based on that, I rescaled all my tables again today. I now have the following columns in my Low/High Det fuel, Timing, and DA (with an extra 4.3 column in the DA).

0.25, 0.50, 0.75, 1.00, 1.25, 1.50, 1.75, 2.00, 2.25, 2.50, 2.80, 3.10, 3.40, 3.70, 4.00

t