throttle lag

[ltcbm]

I have a 2014 ram hemi that I am about to tune. Although I am familiar with chevy and ford tuning like many I am learning on the fly with dodge. This truck has A lot of throttle delay on and off the petal. I know the torque management works different on these dodges and you cant just 0 it out to eliminate some of the throttle lag. Does anyone here have any pointers for the best way to attack this? Thanks for your help.

[ltcbm]

From what I gather from reading on the subject, modifying the petal power % request will help in throttle lag. but the expected petal has to be the reverse of this (although on some other tuners its not). does anyone have a spreadsheet for this? or any insight to this. Also under desired throttle it has a ramp rate. I am unsure the function of this. I attached my stock file to look at.

[ltcbm]

I was hoping that someone would know something about this. I know it is fairly new here but with others experience with the other tuning software I thought someone would have some insight here.

[ltcbm]

Got It. Tune seems to work great. No throttle lag on or off throttle. Power comes in instantly not slowly like with canned tune. I do not have cmr software but I did pay for a custom tune from a major cmr tuner after I purchased the truck just to get rid of the severe throttle lag. It wasn't much better than stock. Not a knock on the software cause its limited to the tuners abilities and knowledge. I am so happy hptuners is now supporting this ecm. Surprisingly the 8 speed trans even feels much better now. Even though we can not tune tcm, just eliminating trans TM makes a big difference. I have tuned many gm and fords pcms and there is always a positive difference between custom tuning one and a canned tune. But never such a night and day difference like this GPEC2. Even the older dodges are not this impressive when tuned. Thanks once again guys for the great work with this system . I have efi live and sct software but the rate you guys are adding support and quality support with ford and dodge controllers( and of coarse gm). You guys tail lights are disappearing in the distance for you competitors. Thanks

[Ls3sierra406]

Looks like you figuered it out all by your self buddy I just got in and was seeing your post but yes its under Airflow-Elecrtic throttle-Pedel Power-power%request is the table to modify.

[ltcbm]

Thanks, one of my main concerns/ questions was about the expected petal table. I scaled it to match but was wondering how critical this is. I know that with the cmr software it doesn't follow suit with this. But I read nightmare post on their site about hanging throttles and such. So I didn't take the chance, just scaled to match and maxed out rate ramp.

[fasthemiram12]

Itcbm
I would love to pick your brain regarding tuning these hemi Rams.
I just ordered a HPtuners package hoping it will work for me.
Have a 2012 im doing stroker and 80mm turbo. I am however new yo tuning in general so any help would be much appteciated.

[ltcbm]

There are a lot of people here always willing to help. Takes a little patience sometimes. I would suggest getting familier with the software before you start trying to tune a turbo app. There is lots of good info and how to's on here. Takes lots of studying and reading. I have a strong background in PLC systems as well as efi in automotive applications. And I still had a tuff learning curve when I first started using this software. Like anything it just takes lots of time, it is not plug and play. When you run into something and have a question post it and I or some of the others on this forum will be glad to help.

[veee8]

Care to post up your tune file?

[Road]

Here is a v6 I tuned the throttle lag veee8

[ltcbm]

Here is a starter guide for tuning throttle response. This is just for throttle lag tuning ( no timing, fuel, ect...). Not saying this is the way or only way to do it, Just how I have. As always proceed at your own risk.

To start throttle tuning on the GPEC2 .
Go to Engine>Airflow>Electronic Throttle
Look at the power % request table.
Increase the first few lower voltage columns making it the same across the entire nvratio
Then from .5v on take the top # on each column and make it the same across the entire nvratio range
Then go to expected petal and make reverse of power% table with simple math
see below screen shots. I have stock tables and modified tables.

petal % stk.jpg
petal % modified.jpgpetal % modified.jpg
Then go to Engine> Airflow > electronic throttle > ramp rate and max it out.
ramp rate.jpg
Then go to engine > fuel > general
Disable WOT delay by maxing out vss mph and 0 tps volts.
Change WOT threshold to 2.7059
wot delay.jpg
Go to Engine > torque management > gereral
increase you min and max on torque adapts
disable esp tqmgt
I disabled trans tq mgt also on mine and well as zero out shift tq red, but i'm an auto trans tech so I might be more willing to take chances with this 8 speed then some are.
tq mang.jpg

[MeentSS02]

Boy I wish they had made the Viper this straight forward...pretty much any adjustment to the power % request table will be greeted with limp mode. Then again, we don't have access to an expected pedal table (not sure if there even is one in the Viper calibration). Guess that's what you get when you use a PCM that's unique to the Viper.

I've never driven a hemi Ram, so I'd be curious to see what kind of lag we're talking about here. If you ever get a chance to drive a Gen 4 Viper, you'll have another good data point for the definition of lag.

[Road]

Yea I just multiply the changes in both tables by the same percent pretty simple

[veee8]

My file doesnt have the throttle ramp rate, when you say increase your min and max torque adapts, by how much?

[ltcbm]

you can max your fiction tq adapts but I just multipliy the trans tq adapts by 10. I am sure others do it differently.

[RAM-SS]

nice thread on throttle response, what did you change on your FA power enrich table?

[87lsttop]

I want a thank you for this guide you put together. I am also a NOOB when it comes to the dodges. Mostly tuned GM platforms. After seeing all the different tables in the dodges compared to the older Gm's man is it mind boggling. Anyways I used it for a 2010 Ram 5.7. The power request and expected pedal tables are under Torque Management/ Driver Demand. Kinda hard to wrap your head around it at first due to the inverse relationship. But it makes a big difference. I didnt have access to the ramp rate table in my PCM. Again thanks for the writeup.

[McCloud]

Here is a starter guide for tuning throttle response. This is just for throttle lag tuning ( no timing, fuel, ect...). Not saying this is the way or only way to do it, Just how I have. As always proceed at your own risk.

To start throttle tuning on the GPEC2 .
Go to Engine>Airflow>Electronic Throttle
Look at the power % request table.
Increase the first few lower voltage columns making it the same across the entire nvratio
Then from .5v on take the top # on each column and make it the same across the entire nvratio range
Then go to expected petal and make reverse of power% table with simple math
see below screen shots. I have stock tables and modified tables.

petal % stk.jpg
petal % modified.jpgpetal % modified.jpg
Then go to Engine> Airflow > electronic throttle > ramp rate and max it out.
ramp rate.jpg
Then go to engine > fuel > general
Disable WOT delay by maxing out vss mph and 0 tps volts.
Change WOT threshold to 2.7059
wot delay.jpg
Go to Engine > torque management > gereral
increase you min and max on torque adapts
disable esp tqmgt
I disabled trans tq mgt also on mine and well as zero out shift tq red, but i'm an auto trans tech so I might be more willing to take chances with this 8 speed then some are.
tq mang.jpg

What does maxing out the torque adapts accomplish? Does it force it to keep the torque at 100%?

[thomasjones]

Wanted to give a shout out to the OP regarding this topic. I've got a 2008 Jeep Wrangler and the stock throttle response is garbage. I'm new to tuning, so I'm a bit conservative when changing tables without fully understanding them (a good thing). To date, I've focused on VE tables and using LTFT to account for intake and exhaust mods. I tried tuning a few of the parameters related to WOT delay to address throttle response, which did not yield much success. But after reading this, the Pedal Voltage and % Power tables make so much sense. So I changed the maps to increase throttle response at lower voltages and wow what a difference.

Here is a 2D comparison of the stock response versus my tune at an NVRatio of 30.

stockthrottle.pngmodifiedthrottle.png

The Jeep feels so much more responsive.