TDStuart Tuning Adventure

[engineermike]

I think you are confused about what I am saying. I am saying the car feels like it has no power on MP5. I don't see any reason in the logs so I am thinking it is simply because that cam angle just doesn't support making power. I changed to MP20 and the car felt like it had power again..

I'm not confused about what you’re saying. I’m trying to explain how it works and why it feels weak. You said it feels weak but is the throttle blade opening all the way? It’s a torque based system so for any given mapped point it should open the throttle far enough to achieve driver demand torque. In all of your logs I’ve reviewed, the maf was way below desired airflow, which means it just isn’t opening the throttle enough, leading to brake torque falling far short of desired torque.

That said, the whole reason all of the “top right corner” (high values for both ivo and evc) mapped points exist is to maximize efficiency by creating a pseudo-Atkinson cycle. Your comp cams added more duration to the evo and ivc side of the lobes. My best guess is that for max efficiency you still want the exhaust cam to be fully retarded at cruise and the intake cam to run around +10 rather than +30.

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[tdstuart]

I'm not confused about what you’re saying. I’m trying to explain how it works and why it feels weak. You said it feels weak but is the throttle blade opening all the way? It’s a torque based system so for any given mapped point it should open the throttle far enough to achieve driver demand torque. In all of your logs I’ve reviewed, the maf was way below desired airflow, which means it just isn’t opening the throttle enough, leading to brake torque falling far short of desired torque.

That said, the whole reason all of the “top right corner” (high values for both ivo and evc) mapped points exist is to maximize efficiency by creating a pseudo-Atkinson cycle. Your comp cams added more duration to the evo and ivc side of the lobes. My best guess is that for max efficiency you still want the exhaust cam to be fully retarded at cruise and the intake cam to run around +10.

Yes, the throttle appears to be opening all the way. I added throttle position in Test 6. Look at this post for attachments: https://www.mustang6g.com/forums/threads/tdstuart-tuning-adventure.201824/post-4067551

 

[K4fxd]

I looked at your log and IMO you are logging too many channels. Get down to 5 or 6. Set mass air and desired air mass to the fastest setting then try to make them match at idle. This should teach you what Mike and Mark are saying.

When you are locking mapped points the goal is not to have a powerful great driving car while locked. The goal is to make the air mass and desired air mass be equal.

 

[engineermike]

When you are locking mapped points the goal is not to have a powerful great driving car while locked. The goal is to make the air mass and desired air mass be equal.

This. Locking, or “isolating”, a mapped point is not the final solution. It’s just the only way to tune mapped points. If you’re always blending mapped points then you never really know which one to tune. Once all your desired cam position mapped points are tuned individually, you go back to a typical schedule and it will run good, efficient, and powerful.

 

[engineermike]

Yes, the throttle appears to be opening all the way. I added throttle position in Test 6. Look at this post for attachments: https://www.mustang6g.com/forums/threads/tdstuart-tuning-adventure.201824/post-4067551

Finally got a chance to review this log. For starters, it's only weighting MP5 (or 17) by 75 to 90%. As I have explained, in order to tune a mapped point, it has to be isolated meaning 100% weighting. Otherwise, you don't know which point needs tuning. My advice is, for starters, properly isolate a mapped point. Secondly, do you think that 40/50 is cam timing you want to run permanently at cruise? I'm thinking not at this point as I said in post 826. Pick a cruise mapped point, which will be IMRC closed, to tune. I'm thinking MP 7 (20/40) or if you're ok potentially sacrificing some efficiency, MP 9 (15/15). Make sure it's actually isolated and it's running 100% MP7 or 9 at all times NOT idle and WOT. Do not proceed until this is verified. Also, did you turn off the PID feedback control over throttle angle? If not, this will hide error that need fixing. Once you're properly isolated MP7 or 9 with IMRC closed, continue on working to make MAF = desired airflow using SD model changes.

MP5 is retarding the intake cam 40 deg which puts IVC very late in the intake stroke with your comp cams. The throttle is getting up to 80-90% open and load is still under .4 under 3000 rpm. This is due to reversion, or reverse flow out the intake port during the compression stroke. You would never run this cam timing if you're trying to get max torque, but this was supposed to be cruise cam timing where max efficiency is priority. Obviously, if you needed torques required by loads over .4, you wouldn't use this cam timing. If this cam timing did actually yield higher efficiency, you'd simply migrate out of it and head towards the origin once loads approached .4. The desired airflow vs MAF matches pretty good at low speeds and loads, but diverge drastically at higher speeds and loads. This can be fixed but I wouldn't waste the time if you're not going to use this mapped point permanently.

You're going to have to pick a mapped point management strategy. As you can see, it can be very cumbersome and time consuming to tune each mapped point. You haven't even began to consider changes to the torque and spark models for the very first mapped point you're working on. Ford can do this because they have the resources and computing to automate the process and calibrate 28 mapped points and let it blend all of them, knowing they're all close to accurate. For an individual or even a company like Lund or Roush, it's much more practical to run a minimum number of mapped points and make sure they are right. For you, I would suggest something like 0/0 (starting, ER), 20/0 (idle), 20/40 or 15/15 (cruise), -20/15 (WOT midrange), and 0/15 IMRC open (WOT top end). You'd then add snap lines between all these points in order of increasing load and speed. The idea is the engine only uses 1-2 of these at a time. Then you only need to focus on tuning these 5 mapped points rather than 28 of them.

 

[tdstuart]

Finally got a chance to review this log. For starters, it's only weighting MP5 (or 17) by 75 to 90%. As I have explained, in order to tune a mapped point, it has to be isolated meaning 100% weighting. Otherwise, you don't know which point needs tuning. My advice is, for starters, properly isolate a mapped point. Secondly, do you think that 40/50 is cam timing you want to run permanently at cruise? I'm thinking not at this point as I said in post 826. Pick a cruise mapped point, which will be IMRC closed, to tune. I'm thinking MP 7 (20/40) or if you're ok potentially sacrificing some efficiency, MP 9 (15/15). Make sure it's actually isolated and it's running 100% MP7 or 9 at all times NOT idle and WOT. Do not proceed until this is verified. Also, did you turn off the PID feedback control over throttle angle? If not, this will hide error that need fixing. Once you're properly isolated MP7 or 9 with IMRC closed, continue on working to make MAF = desired airflow using SD model changes.

MP5 is retarding the intake cam 40 deg which puts IVC very late in the intake stroke with your comp cams. The throttle is getting up to 80-90% open and load is still under .4 under 3000 rpm. This is due to reversion, or reverse flow out the intake port during the compression stroke. You would never run this cam timing if you're trying to get max torque, but this was supposed to be cruise cam timing where max efficiency is priority. Obviously, if you needed torques required by loads over .4, you wouldn't use this cam timing. If this cam timing did actually yield higher efficiency, you'd simply migrate out of it and head towards the origin once loads approached .4. The desired airflow vs MAF matches pretty good at low speeds and loads, but diverge drastically at higher speeds and loads. This can be fixed but I wouldn't waste the time if you're not going to use this mapped point permanently.

You're going to have to pick a mapped point management strategy. As you can see, it can be very cumbersome and time consuming to tune each mapped point. You haven't even began to consider changes to the torque and spark models for the very first mapped point you're working on. Ford can do this because they have the resources and computing to automate the process and calibrate 28 mapped points and let it blend all of them, knowing they're all close to accurate. For an individual or even a company like Lund or Roush, it's much more practical to run a minimum number of mapped points and make sure they are right. For you, I would suggest something like 0/0 (starting, ER), 20/0 (idle), 20/40 or 15/15 (cruise), -20/15 (WOT midrange), and 0/15 IMRC open (WOT top end). You'd then add snap lines between all these points in order of increasing load and speed. The idea is the engine only uses 1-2 of these at a time. Then you only need to focus on tuning these 5 mapped points rather than 28 of them.

Good info and that's what i was getting at about the car not having power with MP5.

Ill decide on a good cruise mapped point to start with. MP20 seems to be okay.

Im not sure why the mapped points aren't sticking to 100% (or very close). Should I manually disable other mapped points? I know for MP5/17 log the car was probably hitting some timmed/temp vct degree limit as it seemed to change as the car ran longer. Those are easy to move out of the way.

 

[K4fxd]

One way is to populate the distance tables with only 1 mapped point for all cells.

MP5

 

[tdstuart]

One way is to populate the distance tables with only 1 mapped point for all cells.

MP5

I have the line distance table set to mapped point 5. Still isn't holding. Part of the problem is the limiting based on temp/time like I mentioned.

 

[K4fxd]

WHat is the line distance table

I think this is the PCMtec equivalent table

 

[K4fxd]

Might also need to change the best drivability cells below .7 to MP5

 

[tdstuart]

Might also need to change the best drivability cells below .7 to MP5

Line distance is what actually controls the mapped points right? That table number is corresponding to the distance number not the mapped point... at least that's what I thought.

here is the line distance:

The table you showed corresponds to the line distance table above and the line distance table is what actually points to a mapped point.

Someone correct me if I am wrong but from my testing when doing the ghost cam that's how it works. In this case it works out because line distance 0-7 correspond with MP0-7 but if you set the table you showed all to 8 then it would actually point to MP20.

 

[tdstuart]

For example in hptuners:

If in fuel economy mode and at 4,500rpm with 0.45 load you would go to line distance 9. Line distance 9 for fuel economy is mapped point 21.

I don't know how the blending works with numbers like 8.82 (4000rpm, 0.45 load). Does it blend between the line distance values of 20 and 21? Idk.

 

[markmurfie]

How hard is it for me to calculate myself?

Excel - MP 20 SD test.csv - Excel - 2 July 2024 (loom.com)

Heres a short 5 min video of how I am manipulating the data in excel o get the quadratic, slope, and offset of just one RPM for MP20.

Above 3500, there wasnt a lot of data points in that log.
Around 1600 RPM theres an interesting thing that happened. The filer of +/-250 RPM only returned a single airmass and single estimated MAP.

 

[tdstuart]

Excel - MP 20 SD test.csv - Excel - 2 July 2024 (loom.com)

Heres a short 5 min video of how I am manipulating the data in excel o get the quadratic, slope, and offset of just one RPM for MP20.

So the quadratic term it spits out I use for the quadratic sd table, slope for the slope with imrc closed table, and offset with the MAP at Zero IMRC Closed table?

 

[tdstuart]

Also here are the rpm values it uses:
500
625
1025
1325
1600
1900
2900
3225
3650
3950
4750
5250
5650
6750

Should I rescale these to 8000? And for 500 would I use rpm ranges from 500-625? Or is it like 500 rpm is 0-500, 625 rpm is 500-625, etc?

Edit: I can add 6 more rpm values to expand the tables

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