Calculate Engine TQ --> Calculated Engine HP = Results

[12secSS]

I am not sure if you guys have played around with the Delivered Engine Torque PID found under the Engine/TQ Management portion of the scanner. I wanted to see if this could net some tangible results. I have tried using the Delivered Transmission Torque, but I don't think it is as "accurate". Using the Tq -> HP formula and applying to this PID, I was able to make some logs this morning to verify the results. For my cars specs see below. I locked the transmission in 3rd using the Bi-Directional controls and made a pass from about 3000 rpms to about 6200 rpms. The results were 454 delivered flywheel torque at 4000 rpms and 412 calculated flywheel horsepower at 5500 rpms. Now I know my SS has run 105.11 MPH at a local high elevation track (LACR for you locals) as driven on the street (no slicks or drag radials), and given that a 4L60E has about 18%-22% drive train loss, I should be able to calculate some rear wheel horsepower numbers. But will they correlate? Given the weight of my car currently, and based on the trap speed (I use an excel calculator that works very well with our cars, and it has been proven to me based on my results), the calculated rwhp from my trap speed is ~340 or so. Now if you apply the drive train loss percentage to the Delivered Engine Torque (and my custom PID: Calculated Engine Horsepower) we get 372 "rwtq" @ 4400 rpms and 337 "rwhp" @ 5500. Wow, pretty good! I will substantiate these results soon on a Dynapack dyno, obviously they will differ, due to no "ram air" affect on the FTRA. At least this can calculate if you have gained anything from the previous round of mods. Granted, like all dynos, this is only intended as a tuning tool. And just like a dyno, the numbers are a little choppy, but surprisingly smooth compared to raw dyno data. I will post the log file tonight, as I conducted this while on my way to work, and I do not have a USB nor a means of transferring data from my laptop to another computer.

Car Specs:
2001 Camaro SS
HPTuned via AEM
FTRA
GMS Lid
Ported TB
Stock 2002 LQ4 Long Block
Hooker LT, ORY & Catback
B&M 3000 Stall
3.73 Gears
Auburn Pro Posi
Weight (w/Driver, full tank) ~3800lbs
Otherwise factory stock

I also made a custom PID that calculates Torque Converter Efficiency. It calculated my B&M 3000 at 97% on the top end, pretty darned good.

[eficalibrator]

Good work, George. It's always nice when the math works out correctly. Excellent contribution.

The only caveat here is that you MUST tune the PCM correctly so that it always knows the exact airflow value for this to work. If your airflow numbers are off, the calculated torque number will also suffer. It would appear that George has done his tuning correctly in this case.

[12secSS]

I had a great instructor. Thanks Greg (for the knowledge)!

[xonelith]

Sounds awesome! I'd love to apply this to my GA. Can you post the custom PID? Maybe the ss? I'd be really interested in having something that says HP and TQ at wheels and at the crank, even if it is just an estimate. I think this would definitely help in determining if a mod helped and where it helped.

Thanks!

[12secSS]

Corrected some stuff on my original post, I was going off of memory.

Anyway ... when I get home, after I take the Mrs. out for a lovely dinner , I will see about posting the hpl and cfg files. You will also not that Dynamic Airflow (lb/min) follows the Calculated HP curve almost precisely! As Greg pointed out. Which is also used to accurately graph the MAF Transfer curve, similarly to AFR Error %.

[redhotjamedjimi]

is that the 4l60e in the automatic of my 2200?

[12secSS]

All 4L60Es (as well as the TH700-R4, 4L60) are the same, the efficiency may vary slightly due to different components used (V8 = stronger = less efficient, I4 = weaker = lighter = more efficient).

[magnet]

this is very interesting would love to see PID aswell

[S2H]

I played around with that at home with a buddys car...
even did the dyno comparison...
seems to be close but no cigar if you know what I mean..and it seems to be hit or miss..but it is good to get a rough estimate of peak torque and peak HP rpm's and can make street tuning a little easier to see gains assuming you get the same conditions every time..
I made an excel sheet once so I could plot it all...and do a couple of runs to see the differences...
seems to be too inconsistent on the street...too many variables...

only sure way to know is the Dyno..and the track is just the proof positive of it when you are thru.

[12secSS]

Scott,

Yes, I hope people do not take this as a replacement for dyno numbers. It is a great tuning tool, but to be accurate, it must be done on the 1:1 gear ratio (Autos = 3rd, Manuals = 4th). Any other ratio will skew the results. But like dynos, you can not compare one dyno results to a different one (Mustang vs DynoJet vs SuperFlow vs DynaPack), and some dynos during different conditions. This is a tuning tool for seeing the HP improvements, much like a dyno or track testing. But like the track, if you =

Having said all of that, here are the files. Reference frames: 1540 - 1600 in the hpl file.

[xonelith]

Thanks for the info. One question, what is PID.2701? It's not available on my ga.

[12secSS]

That is Delivered Engine Torque, it is essential for this to work. You may also use Delivered Trans Torque.

[12secSS]

I had an opportunity to test out my dyno config on a surprisingly impressive setup, that I tuned over the weekend. You can read about it here:

http://www.ls1tech.com/forums/showthread.php?t=660917

On my test run, we made those numbers posted ... well here is what the ECM said we made. Horsepower was 97% and torque was 94% of what the dyno results were, and I backed up those numbers on the second run in the log file. I can honestly say that these results are accurate enough to conduct real world testing. I attached an image of the first scan, where in the histo you can see the (high) torque vs. rpms, while in the table display and graph you can see the calculated horsepower, which the ECM calculated based on airflow. Happy tuning!

[EC_Tune]

George, that thing was really efficient. I only saw the MAP drop to 96 Kpa. Not BAD!


Did you change the MBT Spark tables to get those results?
If so, can you post the before & after MBT Spark tables?

[xonelith]

That is Delivered Engine Torque, it is essential for this to work. You may also use Delivered Trans Torque.

Thanks. D. Trans Tq is pid 4401 Thanks again for sharing!!!

[markislive]

Scott,

Yes, I hope people do not take this as a replacement for dyno numbers. It is a great tuning tool, but to be accurate, it must be done on the 1:1 gear ratio (Autos = 3rd, Manuals = 4th). Any other ratio will skew the results. But like dynos, you can not compare one dyno results to a different one (Mustang vs DynoJet vs SuperFlow vs DynaPack), and some dynos during different conditions. This is a tuning tool for seeing the HP improvements, much like a dyno or track testing. But like the track, if you =

Having said all of that, here are the files. Reference frames: 1540 - 1600 in the hpl file.

This is a pretty cool writeup. I would really like to add this feature to my Scanner. I tried to edit and save my VCM Scanner.cfg file with the lines listed in your PIDs.txt file. Everytime I reopen the VCM Scanner.cfg the 2 new entires I made dissapear. Can someone point please point me in the right direction?

Any tips leads or suggestions would be greatly apperciated.

I attached my VCM Scanner.cfg file....

[jimmyblue]

I guess the thing that I wonder about is, whether the Delivered
Torque responds properly to things like spark timing when a motor
has been substantially modified (CR, cam, exhaust scavenging).
You would think the spark point for best torque would move some
and then so would the Delivered Torque for off-peak (or on)
spark positions. But how do you teach the PCM about this (and
for that matter how would you know without copious data)?

The result is good; I am interested in figuring out how far you
can go with mods and still trust the Delivered Torque result.

[12secSS]

I finally had an opportunity to test the results out versus the Dynapack Dyno (this type of dyno actually measures true RWTQ) that I previously mentioned. See here:

http://www.hptuners.com/forum/showthread.php?t=14284

I have attached two images showing the difference from my Logged power numbers vs my dyno results vs my locked converter dyno results, in both table and graphical displays. Pretty interesting to note that the difference from the dyno results is 87% (on average) of the Delivered Engine TQ.

Use these PIDs at your own discretion, but remember that it is not an end all replacement for true dyno results.

[MNR-0]

U gotta taker into accoutn drivetrain losses after BHP. So, its possible if u are a manual, you are seeing 13% drivetrain loss, and there u are.

[My90Iroc]

Great info. I tried to set up the PID with the funcion ([PID.2701]*[PID.12])/5252 and it came up as unsupported parameter. At the same time I tried a PID to just show Delivered Engine Torque by just using PID.2701 as the function. Again with the same result of unsupported parameter. What am I missing?


On a side note, whenever I try to download a file from this site such as the cfg., hpl., or txt. files listed above, none of them open correctly or even show up with the proper icon. I tried to just do an "open with" on the txt file but all that opened was something that looked like the login screen for this forum. I'm lost, lol. Thanks.

Brian