LS4 Performance Grand Prix GXP | Monte Carlo SS | Impala SS | LaCrosse Super

Torque Converter Allowed to slip

Thread Tools
 
Search this Thread
 
Old Oct 12, 2015 | 02:31 AM
  #1  
Sint3k's Avatar
Thread Starter
TECH Fanatic
 
Joined: Jun 2007
Posts: 1,316
Likes: 3
From: Dolla$ , TX
Default Torque Converter Allowed to slip

So, One of the reasons i got a new transmission long ago is I thought there was a slip while in 3rd and 4th gear. When giving the gas on the highway you can see the rpms rise and then "Grab" again.

Long story short after i got my TEP transmission the same occurred.

I'm merely writing this hear because someone else mentioned this on another forum and wanted to educate whoever may be confused about what is going on and how to fix it.


Long story short, the torque converter is set as low as 10% Pulse Width Modulation. For a lack of a better explanation, its at 10% clamping power. When it detects slip it slowly increases the "clamping" power until it stops. Then it slowly drops it back down to 10% allowing it to happen all over again. This is a recipe for eaten Torque converter clutches and material in the pan.

With HP Tuners or whatever software will allow you to modify the torque converter i would set the minimum to 90% and the max to 100%. The car will never use 100% unless it has an issue with slip at 90% which it should not. If it does then your clutch is on its way out anyways.

After making these adjustments you will be able to push the gas and the rpms will rise 1:1 with the speed of the vehicle, instead of acting like the TCC is not even engaged at all and allowing the rpms to jump up before the converter "grabs" again.

If you do not have a built transmission this may not be a good idea for you. Maybe start off at 50% minimum across the board.

Also another thing to note, this will cause the TCC to engage quickly. It will feel like a gear shift when engaging.


Last edited by Sint3k; Oct 12, 2015 at 02:40 AM.
Reply
Old Oct 12, 2015 | 02:24 PM
  #2  
91parkave's Avatar
Moderator
15 Year Member
iTrader: (4)
 
Joined: Feb 2008
Posts: 2,079
Likes: 9
From: Arizona
Default

I'm still on my stock trans and converter using 100 and 90 been that way for the last 30k miles. I would highly recommend scaling your lockup/unlock speed though in realtion to tps. I feel 55mph is a little too low and can bog a little to much for my taste
Reply
Old Oct 12, 2015 | 03:09 PM
  #3  
spawne32's Avatar
TECH Fanatic
iTrader: (2)
 
Joined: Jan 2014
Posts: 1,524
Likes: 4
Default

I have the updated TCC apply valve and 100/90 was way to harsh for the TCC engagement. I left those settings alone. My TCC apply and release settings are as follows, no issues with bogging....

Reply
Old Oct 13, 2015 | 01:42 AM
  #4  
Sint3k's Avatar
Thread Starter
TECH Fanatic
 
Joined: Jun 2007
Posts: 1,316
Likes: 3
From: Dolla$ , TX
Default

Originally Posted by 91parkave
I'm still on my stock trans and converter using 100 and 90 been that way for the last 30k miles. I would highly recommend scaling your lockup/unlock speed though in realtion to tps. I feel 55mph is a little too low and can bog a little to much for my taste
I'm running 3.69 chain, my rpms are abit higher,I had no issues, I'm not a fan of the linear setup.I just like to know where it's on and off at.
Reply
Old Oct 17, 2015 | 08:17 AM
  #5  
Koren's Avatar
Launching!
 
Joined: Oct 2015
Posts: 200
Likes: 0
Default

Originally Posted by Sint3k
So, One of the reasons i got a new transmission long ago is I thought there was a slip while in 3rd and 4th gear. When giving the gas on the highway you can see the rpms rise and then "Grab" again.

Long story short after i got my TEP transmission the same occurred.

I'm merely writing this hear because someone else mentioned this on another forum and wanted to educate whoever may be confused about what is going on and how to fix it.


Long story short, the torque converter is set as low as 10% Pulse Width Modulation. For a lack of a better explanation, its at 10% clamping power. When it detects slip it slowly increases the "clamping" power until it stops. Then it slowly drops it back down to 10% allowing it to happen all over again. This is a recipe for eaten Torque converter clutches and material in the pan.

With HP Tuners or whatever software will allow you to modify the torque converter i would set the minimum to 90% and the max to 100%. The car will never use 100% unless it has an issue with slip at 90% which it should not. If it does then your clutch is on its way out anyways.

After making these adjustments you will be able to push the gas and the rpms will rise 1:1 with the speed of the vehicle, instead of acting like the TCC is not even engaged at all and allowing the rpms to jump up before the converter "grabs" again.

If you do not have a built transmission this may not be a good idea for you. Maybe start off at 50% minimum across the board.

Also another thing to note, this will cause the TCC to engage quickly. It will feel like a gear shift when engaging.

So that's why after cruising for awhile and you try to reengage the gas it feels like a jerk with the rpms raising?
Reply
Old Oct 17, 2015 | 09:25 AM
  #6  
Sint3k's Avatar
Thread Starter
TECH Fanatic
 
Joined: Jun 2007
Posts: 1,316
Likes: 3
From: Dolla$ , TX
Default

Originally Posted by Koren
So that's why after cruising for awhile and you try to reengage the gas it feels like a jerk with the rpms raising?

yes, thats exactly it. The torque converter slips a tad and regrabs so you get a shutter feeling when giving it gas after cruising. You could also be giving it enough gas to cause the Torque Converter to unlock entirely and then relock together. The way i have mine setup, it engages the clutch so fast and hard it feels like a gear change, which is fine with me.
Reply
Old Oct 17, 2015 | 09:37 AM
  #7  
Koren's Avatar
Launching!
 
Joined: Oct 2015
Posts: 200
Likes: 0
Default

Originally Posted by Sint3k
yes, thats exactly it. The torque converter slips a tad and regrabs so you get a shutter feeling when giving it gas after cruising. You could also be giving it enough gas to cause the Torque Converter to unlock entirely and then relock together. The way i have mine setup, it engages the clutch so fast and hard it feels like a gear change, which is fine with me.
If I let up off the gas on mine and then push down it opens up with no problem, that's odd in glad it wasn't just me. I should have my tune looked at but I went to a shop to get mine
Reply
Old Oct 17, 2015 | 01:26 PM
  #8  
91parkave's Avatar
Moderator
15 Year Member
iTrader: (4)
 
Joined: Feb 2008
Posts: 2,079
Likes: 9
From: Arizona
Default

Ask them to email you the file we will gladly loom at it for you
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

 Pouria Savadkouei
story-1

Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

 Verdad Gallardo
story-2

7 Most Reliable High-Performance Engines GM Has Ever Built

 Verdad Gallardo
story-3

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-4

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-5

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-6

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-7

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-8

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-9

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
Old Oct 18, 2015 | 03:01 PM
  #9  
Koren's Avatar
Launching!
 
Joined: Oct 2015
Posts: 200
Likes: 0
Default

Originally Posted by 91parkave
Ask them to email you the file we will gladly loom at it for you
I'll call him to get it tommarrow probably or stop by, he's a pretty busy guy so I may have to bust his *****. I got the tune done here at performance by joe in St. Louis, he's pretty good at corvette and viper tunes, at the time I got it done he couldn't really be agreesive at it cause I was running cheap gas instead of premium, so my tune is built for 91+ incase I ever drive out of town
Reply
Old Oct 18, 2015 | 05:16 PM
  #10  
Sint3k's Avatar
Thread Starter
TECH Fanatic
 
Joined: Jun 2007
Posts: 1,316
Likes: 3
From: Dolla$ , TX
Default

Originally Posted by Koren
I'll call him to get it tommarrow probably or stop by, he's a pretty busy guy so I may have to bust his *****. I got the tune done here at performance by joe in St. Louis, he's pretty good at corvette and viper tunes, at the time I got it done he couldn't really be agreesive at it cause I was running cheap gas instead of premium, so my tune is built for 91+ incase I ever drive out of town
We would love to see the tune, and actually see if anything was really done.
Reply
Old Oct 19, 2015 | 11:07 AM
  #11  
blkchevyz's Avatar
TECH Fanatic
20 Year Member
 
Joined: Oct 2003
Posts: 1,101
Likes: 0
Default

im going to have to look at that as well. i have a tep transmission with his transmission tune but it still feels sloppy.
Reply
Old Oct 19, 2015 | 11:32 AM
  #12  
spawne32's Avatar
TECH Fanatic
iTrader: (2)
 
Joined: Jan 2014
Posts: 1,524
Likes: 4
Default

Originally Posted by blkchevyz
im going to have to look at that as well. i have a tep transmission with his transmission tune but it still feels sloppy.
Define sloppy?
Reply
Old Oct 19, 2015 | 12:01 PM
  #13  
Koren's Avatar
Launching!
 
Joined: Oct 2015
Posts: 200
Likes: 0
Default

Originally Posted by blkchevyz
im going to have to look at that as well. i have a tep transmission with his transmission tune but it still feels sloppy.
Wait you said his tune? You got a tune by joe or by tep?
Reply
Old Oct 19, 2015 | 01:32 PM
  #14  
blkchevyz's Avatar
TECH Fanatic
20 Year Member
 
Joined: Oct 2003
Posts: 1,101
Likes: 0
Default

by tep.

havent really compared to stock but i dont think he does much other than adjust for the steeper gears.
Reply
Old Oct 19, 2015 | 01:48 PM
  #15  
spawne32's Avatar
TECH Fanatic
iTrader: (2)
 
Joined: Jan 2014
Posts: 1,524
Likes: 4
Default

Originally Posted by blkchevyz
by tep.

havent really compared to stock but i dont think he does much other than adjust for the steeper gears.
What gearset you running? When I did the tune for my 3.29 gears I copied most of the settings from the Comp-G which had those gear ratios stock, including the tcc lockup settings. Obviously some adjustments were tweeked so they were more to my liking but you get the idea.
Reply
Old Oct 19, 2015 | 02:04 PM
  #16  
severancej's Avatar
On The Tree
 
Joined: Aug 2013
Posts: 157
Likes: 1
Default

Another reason diablows.
You Rebuild a trans, nice new converter then the damn modified stock tune ruins it over time.. smh
I'm getting hp tuners, i bet even my silverado could benefit.
Reply
Old Oct 19, 2015 | 02:33 PM
  #17  
blkchevyz's Avatar
TECH Fanatic
20 Year Member
 
Joined: Oct 2003
Posts: 1,101
Likes: 0
Default

Originally Posted by spawne32
What gearset you running? When I did the tune for my 3.29 gears I copied most of the settings from the Comp-G which had those gear ratios stock, including the tcc lockup settings. Obviously some adjustments were tweeked so they were more to my liking but you get the idea.
3.29 as well
Reply




All times are GMT -5. The time now is 02:18 AM.

story-0
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Slideshow: We take a close look at the ONE and Artidiag 800BT2 diagnostic tools from Topdon and the reasons to buy one over the other.

By Pouria Savadkouei | 2026-05-28 11:05:11


VIEW MORE
story-1
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Slideshow: The controversial Ferrari F6 swaps its original flat-12 for a Corvette Z06-derived LT4 V8 and sends power to four rear wheels through a custom-built drivetrain.

By Verdad Gallardo | 2026-05-26 18:23:54


VIEW MORE
story-2
7 Most Reliable High-Performance Engines GM Has Ever Built

Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.

By Verdad Gallardo | 2026-05-21 16:45:27


VIEW MORE
story-3
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-4
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-5
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-6
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-7
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-8
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-9
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE