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-   -   1st gear torque management? (http://www.jeepgarage.org/f97/1st-gear-torque-management-60631.html)

14srt 05-28-2013 03:39 PM

1st gear torque management?
 
I know it has been discussed that people are noticing sometimes when using launch control it seems at though the truck is getting shot out of a cannon, and sometimes it feels much more sluggish and does not really get going until 2nd. The gear shifts are fantastically quick, almost pulling you harder at each click, but 1st seems to be bogged down.

Just yesterday under the same weather conditions as today I just floored it off a light leaving the highway (in sport no launch control) and all 4 tires spun about 1 rotation and I was gone. Head slamming into the seat kind of gone! Now today I cant best a 5.1 0-60?!

How extreme is the power management in 1st gear? It seams as though sometimes it does not work (glitch?) and just lets you go, and sometimes dials the car back.

Anyone have insight yet?

HAMMMERHEAD 05-28-2013 04:23 PM

Re: 1st gear torque management?
 
Dont power brake it much. Anything over 1000rpms would cause the nanny to kick in on my '12 and the 0-60 would suffer.

Lankness 05-28-2013 08:29 PM

Re: 1st gear torque management?
 
I've been asking the same thing. I've had 2 launches with the LC that let a little tire slip go and it was a ROCKET (3.9 and 4.1 according to the EVIC). Those were on back to back runs with 505 miles on the ODO. I have not been able to recreate it since... Before those 2 and ever since I click off 4.5-4.6 launches with zero wheel spin.

I know I didn't do anything different for those 2 runs, but the Jeep certainly did. Only thing that I can think of would be air temp, but it will be months before we have cool weather here again.

A.V.GCSRT8 05-29-2013 09:06 AM

Re: 1st gear torque management?
 
My tuner pulled some torque management at launch to try and quiet some knk in my latest revision so I will keep you guys posted as to whether its that or not as soon as I get a log. It does seem more consistent at launch with a tune though, custom or canned

HAMMMERHEAD 05-29-2013 10:06 AM

Re: 1st gear torque management?
 
I dont see how they let the tranny (at least in the old 5 speeds) bang the gears so hard when manual shifting and then turn around and let torque management make the launch suffer so bad. Do the new 8 speeds hammer the shifts like the old 5 speeds??

Lankness 05-29-2013 10:13 AM

Re: 1st gear torque management?
 
They shift hard. The whole difference in time/feel for me is the first 20'.

Wheelman 05-29-2013 12:06 PM

Re: 1st gear torque management?
 
Have you been able to powerbrake and repeat the aggressive launch?

It almost sounds like the LC has a built in learning process. The first few may be very aggressive, and the computer compensates to dial into that 4.5 sweet spot with minimized drivetrain stress.

I will give my feedback in about 3 weeks :)

14srt 05-29-2013 12:35 PM

Re: 1st gear torque management?
 
I have actually noticed that power braking, even the slightest bit, make the launch even softer. Throttle slammed out of the hole is the quickest for me. I have only achieved a 4.5 once, with 500 miles. Have bested a 4.7 since then (with a slight downhill for the 4.7....)

Lankness 05-29-2013 12:39 PM

Re: 1st gear torque management?
 
There were launches by me with LC prior to 500 miles. I figured that the 2 good ones at 505 miles were because the computer "knew" about the break-in period. I was disappointed the following day (and couple of weeks having to listen to the BS on the forums about what I posted) when I couldn't recreate it.

...so, learning mode is out :) (At least in the sense that it didn't start out strong and become weaker).

A.V.GCSRT8 05-29-2013 02:12 PM

Re: 1st gear torque management?
 
Do you guys with the 8 speed get the hesitation between 3-4k? Only way I have been able to get rid of it is to mess with the throttle booster. While at the track my first launch was so so the 2nd was a little better and the 3rd it launched like a bat out a hell, cut a 1.76 60 ft which I have never done even in my 08. Launch just above idle has seemed to work best for me, barely enough to tighten the drive line.

Lankness 05-29-2013 02:23 PM

Re: 1st gear torque management?
 
I don't notice any hesitation anywhere. Once it starts pulling it is smooth the entire RPM band.

Of course I don't have a way to play with tuning/watch anything. I really wish they had something like the HPTuners software I have for my Camaro.

A.V.GCSRT8 05-30-2013 01:08 PM

Re: 1st gear torque management?
 
Went out and got a log last night to send back and there is a difference for the better. Knock didnt get higher the more I beat on it and it did not knock as much at launch


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