[wookwook]

I've been starting to look around at the world of VVT. Anyone have any insights? I have the back story on static grinds vs VVT but not considering a radical cam change at this time. This is for 2T application. As far as I can tell they seem to be reporting a minimal impact. Retard at the high end for HP gains? Is there any issue with rotation angles, are cams locked into a safe operating window? within say 2-4 degree deltas? I do my own tuning and have the Gen V books.

thanks in advance!
W..

[wookwook]

I just gotta say I was out tonight running a series of test runs on some new VVT settings and I happened upon a Mustang EcoT. I have to say that exhaust is the worst of all small turbos out there bar non. That's all. I ran a series of adv/retard studies for stock, +6 and +8 degrees on intake and similar exhaust. It will take a couple days to crunch the numbers. but I can say I did log affected rotations on the cams I was able to adjust in VCS. this is for 2T application. stay tuned.


that's a good signature phrase "stay tuned"!

[cooper1965]

Interested in seeing your data. You will notice that no matter the settings, intake position will not change at WOT from 16.1 or so in the logs.

[wookwook]

Yeah! I think that is def the case. I don't want to sound like a premadonna - or the smartest guy in the room. so I am softening up the ground here. I took a course in grad school about process optimization. It was at the turn of the japanese quality revolution in the 80s. The usual case study was like deposition defects on ICs, wave soldering and the like. Defect reduction and process improvement with shorter number of test runs. Called orthogonal arrays.


The mechanics of it are below for the daring.


Bottom line is it will give 'pointers' in the direction that the changes will
give you the improvement, i.e. better torque curve.


you can iterate the process to find the peak improvements.



it keeps me out of trouble....



================================================== =




Now you gotta bear with me this was 30 years ago (turn of the century). I actually did my term project on what else? CARs - increasing MPG, and yes Premium fuel does result in better MPG!

So my case study has 9 runs and I am testing for mostly AIR as a proxy to power and those are the factors I am measuring.

So I still have some number crunching to do, that part basically amplifies the Signal (result) to the Noise (interactions).
good thing for Excel it wont take much time.


HEre are the parameters.
L9 Orthogonal Array Tested Factor


intake | exhaust | Turbo PR | Max VE

1 1 1 1 1
2 1 2 2 2
3 1 3 3 3
4 2 1 2 3
5 2 2 3 1
6 2 3 1 2
7 3 1 3 2
8 3 2 1 3
9 3 3 2 1


Default Settings are Level 2

NOTE- my default CAM Angles are using my Tuners' Cam settings and they are about 2 degrees retarded already in WOT range.





Decrease - Settings 1
1. Intake Cam advanced in Increments of 4 degrees ( -4, 0 +4) 4.4K to 8.4K RPM Airflow\Variable Camshaft\Intake Camshaft\WOT Desired Angle
Looking at the curve shape taking out the large part of the dip from 5600 on up with a .8 percent multiplier and smoothed back to to 3800

2. Exhaust Cam advanced in Increments of 4 degrees ( -4, 0 +4) 4.4K to 8.4K RPM Airflow\Variable Camshaft\Exhaust Camshaft\WOT Desired Angle
Looking at the curve shape its pretty smooth and low degrees, I went from 3800 to 8400 with a .8 percent multiplier, it lowered the curve smoothly

3. Turbo Pressure Ratio Max Curve ( curve modified by -10%, 0 +10%)
1508-2683 lb per hr Airflow\TurboCharger\Pressure Ratio Based\Pressure Ratio Max tab
using previous MAF airflow RPMS to locate the powerband I want to affect -lowered PR by 10 percent on up did not smooth.

4. Turbo Max VE
( curve modified by -5%, 0 +5%)
5.5 K to 6.5K PRM Airflow\TurboCharger\Volumatric Efficiency\Max VE tab
applied .9 multiplier to 5500 and 6500 cells did not smooth


Increase - Settings 3
1. Intake Cam advanced in Increments of 4 degrees ( -4, 0 +4) 4.4K to 8.4K RPM Airflow\Variable Camshaft\Intake Camshaft\WOT Desired Angle
Looking at the curve shape taking out the large part of the dip from 5200 on up with a 1.20 percent multiplier and smoothed back to to 3800

2. Exhaust Cam advanced in Increments of 4 degrees ( -4, 0 +4) 4.4K to 8.4K RPM Airflow\Variable Camshaft\Exhaust Camshaft\WOT Desired Angle
Looking at the curve from 4200 to 8400 by applied 1.2 mulitplier smoothed back to 3600 once

3. Turbo Pressure Ratio Max Curve ( curve modified by -10%, 0 +10%)
1508-2683 lb per hr Airflow\TurboCharger\Pressure Ratio Based\Pressure Ratio Max tab
using previous MAF airflow RPMS to locate the powerband I want to affect -increased PR by 10 percent on up did not smooth.

4. Turbo Max VE
( curve modified by -5%, 0 +5%)
5.5 K to 6.5K PRM Airflow\TurboCharger\Volumatric Efficiency\Max VE tab
applied 1.1 multiplier to 5500 and 6500 cells did not smooth


First table looks like this. There are 9 Tables to fill out.

cams are advanced | Turbo PR | and Max VE set low- by design


Test 1 Intake Exhaust Turbo PR Max VE
Level 1 1 1 1

Result RPM MAF VE Airflow Torque MAP Boost cyl air Speed
2500 125.73 14.22 301 241.5 34.9 1.29 34
3000 144.15 17.88 338 241.7 34.9 1.41 41
3500 163.43 21.18 333 247.3 35.4 1.41 49
4000 192.54 25.78 353 249.7 36 1.47 56
4500 216.02 29.04 351 251.3 36.4 1.47 63
5000 222.16 31.62 332 248.3 36 1.36 69
5500 227.01 32.78 303 243.1 35.2 1.26 76
6000 229.22 33.71 272 235.9 34.3 1.17 83


Hopfully will have a report this week end.

[wookwook]

Oh Yeah, Cooper I can sent you my VCS graphs/channels if you want.

[cooper1965]

Shoot em over bud!

[wookwook]

will do. and the tune files too i will send in a zip file next time I'm at that pc. might be shopping a mini cooper for the wife tonight. hold tight.

[wookwook]

Welp. I finished the first round test runs on my air project which is cams and turbo VE table and the Pressure Ratio tables. I lined up a series of controlled test runs and used some math that puts out the best result so you can basically cherry pick the best settings and glue that into a new table to try out.


I will take a free 3 percent increase all day long, and I am happy enough, 1. I actually got gains, and 2. found a skew that I would have never known about and interestingly, I didn't work in the lower band, so its an opportunity to clean up the factory table below 3500.



Also - I did verify the baro SAE on the two days I ran the original curve Wot in 3rd and todays tuned run, the baro corrections are negligible, in the hundreds of a point so the weather was basically identical on the 2 tests.


Since weather is bearing in here, it will be a while until I can revisit.
Thanks for visiting.


edit: incidentally this is actually a gain over my existing tune, and not the stock cam profiles. I didn't have a comparable log to use from that time.


W.

[wookwook]

A couple of things I should clarify. Although I am referring to the cams, the test is also for 2 parameters in the turbo gain tables for the 2T. I can say that my results tables were strongly indicating increases for the cam rotations of about-4-6 degrees, but the fact I'm FI, its possible I got more air from the turbo for the cam to affect.

The main point is: moving 4 factors and seeing how together, the changes will give the best result.

Another note: I used Airflow as an approximation for the HP based on airflow, not 5252 - so the HP curve isn't that wonky to the wheels in reality but airflow as it affects HP apparantly was.

snowed in now.

[gmcvt]

Originally Posted by wookwook

I just gotta say I was out tonight running a series of test runs on some new VVT settings and I happened upon a Mustang EcoT. I have to say that exhaust is the worst of all small turbos out there bar non. That's all. I ran a series of adv/retard studies for stock, +6 and +8 degrees on intake and similar exhaust. It will take a couple days to crunch the numbers. but I can say I did log affected rotations on the cams I was able to adjust in VCS. this is for 2T application. stay tuned.


that's a good signature phrase "stay tuned"!

Careful, Lund Racing will want their company slogan back sir: "Stay tuned".

https://www.lundracing.com/