isx torque guage questions

[TB3NNI5]

Long question, hope i explain well and am looking for some knowledge on the subject. To give some background info, 2014 cm2350 factory 485 18 spd with 3.08 rears, when i first got the truck it had already been turned to 500hp per the computer where it shows advertised hp. It was very weak, wasnt holding rail psi, i diagnosed bad injectors and replaced all 6 from peterbilt. Had decent power after and torque guage always went to 100% in a pull and just seemed to pull better. The only problem i had was the truck was always chattery like it had no pilot injection, it eventually through the months seemed to lose power and eventually i could only squeeze 85% torque out of it, i know these are generally vague readings but why would it use to push 100 and now only 85? What causes this? I have since had the truck retuned and got rid of all that chattering and noise it use to make and hazy idle it had. Ive had to do an inframe along the way for dropped liners, intercooler etc. truck is very healthy overall no engine lights etc, if one ever comes up im quick to adress it. Im just very ocd and feel like its not trying as hard as it should. Advertised hp says 601/2250 now, but pulls no better than it did at 500/1850 tuner guy says it should be a good running truck but its just not... Also, does anyone know if i can turn off the “brake lights coming on with jake brake” function with cummins insight?

[PolishHammer]

Those are calculated numbers for torq. Every program you put on the truck unless the file is built for your exact truck will
Have different readings.

A file for your truck means for your engine trans clutch diff tire size and application you use it for.

[TB3NNI5]

Right, im just wondering because before a change in file, it somewhere along the way decided to never show 100% again, there was no change, i guess im just trying to understand, because a 15% power decrease at 600hp= 510hp. Which seems spot on the way its pulling

[PolishHammer]

Torq is not horse power. Your a bit messed up there. Your peak torque doesn't happen at Max horse power. You will have a peak torq at lower rpm and peak horse power at a higher rpm. All the files for the engine are calibrated differently and don't feel the same.

[TB3NNI5]

(02-10-2024 )PolishHammer Wrote:  Torq is not horse power. Your a bit messed up there. Your peak torque doesn't happen at Max horse power. You will have a peak torq at lower rpm and peak horse power at a higher rpm. All the files for the engine are calibrated differently and don't feel the same.

when i mention horsepower im vaguely referring to trucks overall power, but say peak torque at 2050 minus 15% torque, your at 300ft lbs of torque under advertised power at 1200rpm.Maybe my initial question was confusing, the tune change didnt effect the gauge readings, a power loss happened before a tune change, i only mentioned i changed files to give some background history on the truck. I feel like alot of people see a problem like this and just deal with it and call it a dummy gauge, however its hard for me to understand why one day it would quit going to 100% is all. Just trying to learn maybe how that gauge is calculated and if i do have a power loss i would like to resolve it

[tree98]

Because the program was most likely cobbled together by some dumbass that shoves the same terrible tune into every truck he comes in contact with. Jumping modes and making different levels of power and just generally inconsistent, that's a classic bad tune.

You said you already did one inframe due to a dropped liner. I highly suggest you have Rawze look at that program because it's highly likely its causing damage to the engine. Also that 2050 torque will cut its life in half or less, especially with 3.08 rears.

[PolishHammer]

How are you testing what the load change is ? Empty truck with just a trailer or loaded ? With exact same load same road same temperature same fuel same shift points ?

What's the fuel mileage from before and now.

[TB3NNI5]

(02-10-2024 )tree98 Wrote:  Because the program was most likely cobbled together by some dumbass that shoves the same terrible tune into every truck he comes in contact with. Jumping modes and making different levels of power and just generally inconsistent, that's a classic bad tune.

You said you already did one inframe due to a dropped liner. I highly suggest you have Rawze look at that program because it's highly likely its causing damage to the engine. Also that 2050 torque will cut its life in half or less, especially with 3.08 rears.

I dont doubt that, how would i go about having it looked at? i have insight but not much idea on how to read a file or anything. And it says 2050 but like i said theres no way its a 2050 truck its gets pushed around by 2050 trucks on the regular.

[TB3NNI5]

(02-10-2024 )PolishHammer Wrote:  How are you testing what the load change is ? Empty truck with just a trailer or loaded ? With exact same load same road same temperature same fuel same shift points ?

What's the fuel mileage from before and now.

Same roads same loads, i drive the truck 5 days a week, run alot of the same routes at the same weight. The fuel mileage never changed much it will average 4.2-4.5 loaded both ways and its a car hauler so thats pretty normal fighting with wind all the time. You just have to stand up in the seat and cuss it up hills alot of times even on regular interstate hills you may be running 35 at the top of some and im not talking about mountains. I aint interested in it being a dragster but id like for it to maintain on small hills