AVCS - Intake and Exhaust Timing

[KoolBRZ]

Originally Posted by Nah

Just outta curiosity, has anyone ever changed their base tables and achieved positive results?

Base tables are just the section from .15 - 1.0 Load, and from 800 - 6800 rpms. Copy and Paste into the base tables. Base affects how the car runs until it's warmed up.

As far as more or less power goes, more advance makes more noise, but less power after a certain point. I learned that from @shr133. It's important to start with a smooth map. Big changes cause misfires, knocks and other problems. You could be running around in circles fixing problems that didn't need to be if you don't use a smooth AVCS map.

Once you have a smooth map, increase the overlap. Let's call it that. Since it's really increasing the timing advance of the Intake, and increasing the timing retard of the Exhaust. Now change the overlap by shifting the columns one section to the left to increase it, and one column to the right to decrease it. This is how I came up with the numbers shown in the tables above.

[KoolBRZ]

Originally Posted by Nah

Lol nice... Wouldn't those tables cause me to lose power all around though? I mean theres almost a 20 degrees difference in certain areas? I'm looking for max power extraction. Lol but good to have for that drive to cocoa beach I'm planning to make soon.

I've used those 40 degree AVCS tables before. More noise then power. The key to power is containing the expansion long enough to get the most torque out of it, but not so long that it impedes the flow. That point is different for every car, and finding it takes trial and error. Luckily for me, these ECU's can handle thousands of flashes, because I've made thousands of errors.

I'd recommend starting with these tables, then gradually increasing overlap till you reach the point of more noise then power, then back it off until you find the tables with best power.

[Nah]

100 well driven miles later (on e85)... I agree with you on the noise part its much quieter and even noticeably smoother. Have you ever tested your maps out on a dyno?

Next week, i'm planning to go to my local dyno and try to squeeze a little more power outta the frs.

If you want to see how much power your maps make let me know. I'll test em out and should even be able to get you a print out.

[KoolBRZ]

Originally Posted by Nah

100 well driven miles later (on e85)... I agree with you on the noise part its much quieter and even noticeably smoother. Have you ever tested your maps out on a dyno?

Next week, i'm planning to go to my local dyno and try to squeeze a little more power outta the frs.

If you want to see how much power your maps make let me know. I'll test em out and should even be able to get you a print out.

That would be cool. What is your CAL ID?

[Nah]

Yeah man why not! It's A01C

[shr133]

Originally Posted by Nah

Lol nice... Wouldn't those tables cause me to lose power all around though? I mean theres almost a 20 degrees difference in certain areas? I'm looking for max power extraction. Lol but good to have for that drive to cocoa beach I'm planning to make soon.

Some of the stock setting are too high, especially the exhaust cam, too much exhaust cam is for egr effect and makes the engine flat....

So reducing the cam timing and smoothing the map make the engine run much better.........

[KoolBRZ]

Originally Posted by Nah

Yeah man why not! It's A01C

Here are 5 tunes based off of Wayno's "WW v109.2 2016-07-26 A01G" E85 RICH, Tune. I also included the LEAN tune, and the definition file I used to edit.

The only difference between them are the AVCS tables. I'm currently using the one equivalent to the 03 tune. You have 2 tunes with less valve overlap, and 2 tunes with more overlap than the overlap in tune 03. Load all 5 tunes in your OFT and try them all. Keep the one with the best power. If the best one is tune 01, or 05, than send me a PM for more tunes.

This is tuning by trial and error one digit at a time. You'd be surprised how different even 1 degree of change feels.

[Kodename47]

@Nah the way to do cam timing on the dyno is work on one cam 1st and then the other, usually the intake 1st. So vary that 1st and then get the ideal settings and then repeat for the exhaust. Once you have what appears to be the best of both you would then make minor changes to both again to test what happens if you swing the whole curve one way or the other. I haven't looked at the maps @KoolBRZ has done but if you're changing both sets of cams at once you won't know what's making any improvements at all.

If your're working from a working cam profile rather than testing flat values, be aware of the cam limits and actually be smart about it to maximise the benefit of your dyno time. Also, time will dictate how good the final maps are.

[KoolBRZ]

I've developed cam profiles that work best over many different NA or boosted applications. The only thing I change now is to move the whole curve 1 degree left or right to increase or decrease valve overlap. I can't really call it more advanced, or more retarded, since it is both. The Intake advances more, and the Exhaust retards more. So, the only accurate way to describe it is more or less valve overlap. Since the curve doesn't change, it isn't so much what engine speed the changes occur at, earlier or later, but more like at what engine load, (throttle input) the changes occur at, earlier or later.

The only change to the profile curve that would occur would be on the far right side, above 1.0 load, where the maximum advance, or retard, is set. I don't use increased overlap at lower engine loads for EGR, so my curve yields a lower city mpg, but highway mpg is up to 40 mpg, depending on what gearing, tires and etc. you have.

I've tried hundreds of maps to determine the best spacing for the curves on my AVCS maps, and I've found a spacing method which works very well. The Intake is more aggressive than the Exhaust because it works best that way. The Intake spacing as the rpms go up is 1 to 2 between idle and 2k rpms, and then 1 to 3. between 2400 and 3600 rpms. The Exhaust spacing is just 1 to 2, with the same section between 3600 - 4800 advancing between loads, but not between rpms. (see pics below)

I believe the AVCS profiles should be mathematically smooth curves, like the camshaft lobes, without holes or bumps, and that any compensations for localized conditions should be made in the Requested Torque B, Base Timing B, MAF sensor Scaling, and Fueling tables. After all, the AVCS tables are really just an extension of the camshafts themselves, and you wouldn't expect to find a small bump, or hole, in the middle of a camshaft lobe, would you?

[Kodename47]

I wasn't on about your theories (you've stated these enough in the thread already), I was on about the ones you built for his dyno time. If it's just as you've described above, it's not the ideal way to do it on the dyno. However, his time and money.... do it as you like.

Originally Posted by KoolBRZ

I believe the AVCS profiles should be mathematically smooth curves, like the camshaft lobes, without holes or bumps, and that any compensations for localized conditions should be made in......

Why? This is exactly the point of VVT systems, is that you can use the cams for different operating conditions. The issues with larger swings is that the cams don't always keep up with commanded, however there are positives for having a "non smooth" cam map.

[solidONE]

^ he seems happy with the maps KoolBRZ provided him. I'd be curious what the dynos look like.

[Nah]

I am happy with the maps Kool Brz provided and if you could look at your inbox I sent you a PM.

the 01 tune you sent me is still breaking in but its smooth really peppy yes the dyno time will def be happening! im gonna still street test to find the smoothest maps for the street before i head on over to the dyno.

also im gonna test everyones theories on here. lets see what happens haha...

[KoolBRZ]

Originally Posted by Nah

I am happy with the maps Kool Brz provided and if you could look at your inbox I sent you a PM.

the 01 tune you sent me is still breaking in but its smooth really peppy yes the dyno time will def be happening! im gonna still street test to find the smoothest maps for the street before i head on over to the dyno.

also im gonna test everyones theories on here. lets see what happens haha...

I should have told you up front that you don't need to break in each tune. The AVCS isn't one of those things that settles or breaks in over time, so you can actually try all 5 tunes in under an hour. It should be obvious which one develops the best power. If it turns out tune 1 or tune 5 is best, I'll be making more tunes for you.

After we find which tune works best, then we can try adjusting the AVCS Intake only, or the Exhaust only. The AVCS tables weren't developed for E85, so the difference between the Intake and Exhaust tables might be closer, or farther apart, and the limits might be farther up. If E85 was locally available, I'd already have most of this done already.

[Nah]

So from further testing of those 5 maps KoolBRZ kindly shared for me I have come to this conclusion.

Map 01 has the most power overall but a little too jumpy while cruising.

Map 05 had the smoothest downshift between 4-6k and was also the most linear map but lacked the top end power map 01 had. cruising was very easy.

Map 04 was a combination of the two.

Take a look at the maps and come to your own conclusion... im actually gonna combine both 01 and 05. ill use 01 maps from .85 and up and 05 from .8 down. Ill let you know how that goes.

however only the dyno will tell....