AVCS - Intake and Exhaust Timing

[ztan]

Originally Posted by Kodename47

Please do explain then how the base/normal/safe all interact....

Just had a look at the disassembly.

There is an interpolating factor at FFF89C88 (A01G) which is used to interpolate between AVCS Intake Base table and the return from AVCS Intake Safe/Normal table (Safe/Normal switch is determined by IAM with hysteresis). Exhaust code is virtually identical. Have not logged FFF89C88 to see when it is active, but presumably not very much.

[KoolBRZ]

I would also like to know how many cells it averages. Is it a 3 cell spread across rows, and a 5 cell spread down columns? I know there is a spread for smoothing. I would just like to know how wide it is to know how long a change will last across RPM's or Load. Also, which is the more advanced table, and which is the less advanced table, Safe or Normal, as determined by the IAM.

[Kodename47]

@ztan that's how I was told and that's why base and the safe maps are set the same (or all 3 in my case).

Originally Posted by KoolBRZ

I would also like to know how many cells it averages. Is it a 3 cell spread across rows, and a 5 cell spread down columns? I know there is a spread for smoothing. I would just like to know how wide it is to know how long a change will last across RPM's or Load. Also, which is the more advanced table, and which is the less advanced table, Safe or Normal, as determined by the IAM.

There is no smoothing.

Safe = IAM high
Normal = IAM Low

I have defined boundary of IAM = 0.4 for the normal/safe determination.

[shr133]

Originally Posted by KoolBRZ

I tried out a tune with modified base maps yesterday. It felt like too little, too much. Not much under 2800 RPM, then it really screamed. AFR's were all over the place. I switched back to a known good tune right away. I've found it's always good to keep at least one known-good tune in my OFT, then try out with the other four tunes. Today I'm trying out slightly de-tuned Base tables. I reduced the highest numbers and smoothed out the dips, since I am FI I don't need compensation for the dips. If it works better I will post it. I have determined, however, that the Base tables are active, no matter what temp the engine is at.

That's why I need to upgrade to race rom so I can run maps back to back...
I'm not sure when the base map would take over so far now make all the maps the same so I know for sure what I like or don't like...

Hopefully it warms up again so I can do some tweaks....
Below 20 last couple of days.... Hates the

[ztan]

Originally Posted by KoolBRZ

I would also like to know how many cells it averages. Is it a 3 cell spread across rows, and a 5 cell spread down columns? I know there is a spread for smoothing. I would just like to know how wide it is to know how long a change will last across RPM's or Load. Also, which is the more advanced table, and which is the less advanced table, Safe or Normal, as determined by the IAM.

The Pull2D and Pull3D functions do not smooth across cells - they are direct linear interpolation based on the 2 nearest values in a 2D table and 4 nearest values in a 3D table.

[KoolBRZ]

Originally Posted by Kodename47

@ztan that's how I was told and that's why base and the safe maps are set the same (or all 3 in my case).

There is no smoothing.

Safe = IAM high
Normal = IAM Low

I have defined boundary of IAM = 0.4 for the normal/safe determination.

Could you show the tables you have created for Base, Safe, and Normal?

[Kodename47]

Originally Posted by KoolBRZ

Could you show the tables you have created for Base, Safe, and Normal?

All 3 are set the same on mine.

I can't post them for 2 reasons:
1) They're not my cam maps
2) If I use the ECUtek custom maps, it renders these irrelevant.

[ztan]

Originally Posted by KoolBRZ

Could you show the tables you have created for Base, Safe, and Normal?

Greddy T518Z turbo. Base maps similar, Safe and Normal identical.

[KoolBRZ]

Thank you @ztan. Once again, the beauty of using Open Source software is the ability to show what you know without being sued for it.

[ztan]

Originally Posted by KoolBRZ

Thank you @ztan. Once again, the beauty of using Open Source software is the ability to show what you know without being sued for it.

I agree. As you're well aware, Open Source is my preferred route.

Credit @Shiv@Openflash where credit is due. The AVCS map I use is based on his OFT350 work, running less overlap in a few areas where I was still getting quite a bit of knock. Not sure if this was due to running a turbo that spools just that bit quicker, local environment and fuel, or just the way I drive (on the road, not on the dyno).

[KoolBRZ]

These maps feel a bit tame under 3000 rpms. I like what @shr133 did at the low rpms, so I'm going to do some blending and I'll post what I find works for me.

[shr133]

Originally Posted by ztan

Greddy T518Z turbo. Base maps similar, Safe and Normal identical.

I was wondering what a turbo map would look like....
A turbo may be in the future...

[shr133]

I tweaked my maps a little, I'm bring in the cam timing faster moving my map 1 step to the left and going to a max of 35 degrees of intake...

The biggest thing is I went to 5 degrees less exhaust timing with a max of 25 degrees...

Feels less "torquey" but revs much better and seams to run cleaner...
Have to drive it a little more but spun the tires good going to second for the first time so it must be running better...

I think I'm really close on the maps, now I'm working on the optimum split...

[KoolBRZ]

Originally Posted by shr133

I tweaked my maps a little, I'm bring in the cam timing faster moving my map 1 step to the left and going to a max of 35 degrees of intake...

The biggest thing is I went to 5 degrees less exhaust timing with a max of 25 degrees...

Feels less "torquey" but revs much better and seams to run cleaner...
Have to drive it a little more but spun the tires good going to second for the first time so it must be running better...

I think I'm really close on the maps, now I'm working on the optimum split...

Can you show pics?