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Old 09-13-2011, 11:57 AM
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Default weight transfer at launch questions

My car launches and leaves pretty straight but I just dont think its being efficient in the first 60 ft. Im cutting 1.61-1.65 60ft and spinning a little.

I cut 1.60-1.62 on 26" QTP bias plys and 1.64-1.65 on 28" MT ET street DR's

When the car launches it bring the left front up twists and tucks the right rear tire in the wheel well, on a nitrous launch of course its twice as bad. Ive tried tighting up the right rear shock but it either makes it where it doesnt hook up or not enough where it still puts the weight on the right rear.

The car has
QA1 12 ways on all 4 corners
BMR ADJ Torque Arm
BMR Torque arm relocation transmission crossmember
UMI 2 point subframe connectors
6 point rollbar
No front sway bar
Factory rear sway bar
3700lb Race weight

Is the factory rear sway bar my problem? The car is still a street car and I dont really want to run the Dragbar, would the heavier duty one help?
Old 09-13-2011, 12:01 PM
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Originally Posted by 355z28
My car launches and leaves pretty straight but I just dont think its being efficient in the first 60 ft. Im cutting 1.61-1.65 60ft and spinning a little.

I cut 1.60-1.62 on 26" QTP bias plys and 1.64-1.65 on 28" MT ET street DR's

When the car launches it bring the left front up twists and tucks the right rear tire in the wheel well, on a nitrous launch of course its twice as bad. Ive tried tighting up the right rear shock but it either makes it where it doesnt hook up or not enough where it still puts the weight on the right rear.

The car has
QA1 12 ways on all 4 corners
BMR ADJ Torque Arm
BMR Torque arm relocation transmission crossmember
UMI 2 point subframe connectors
6 point rollbar
No front sway bar
Factory rear sway bar
3700lb Race weight

Is the factory rear sway bar my problem? The car is still a street car and I dont really want to run the Dragbar, would the heavier duty one help?
What you are describing is what I was having issues with. I did end up going with a drag bar from UMI which is streetable but definitly not meant for taking hard corners under power.

Spohn makes a heavier then stock rear bar if I recall it had issues hitting the QA1 shocks.

There are people here better then I to answer this but getting the car to leave straight is half off the equation.

https://ls1tech.com/forums/eastern-m...ay-new-pb.html this is a few years old but basically what I was dealing with.
Old 09-13-2011, 12:54 PM
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I think my UMI drag bar helped handling since I have no front bar. Def not a road race car but better then the stocker without the front sway bar.
Old 09-13-2011, 01:09 PM
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Those pictures of your car is basically what mine is doing, I have the LF up about 12" or so and the left 3-5" and the whole body is transfered the the right rear with a huge wheel gap in the left rear wheel well.

Sound like Ill have to look into a drag bar. Its odd because I didnt have this problem last year and the only thing that has changed is I relocated my battery to the Right rear spare tire well. I would've never imagined it would throw it that far off.
Old 09-13-2011, 01:35 PM
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You may have been doing it, but maybe people did not notice. Also getting that boat anchor in the back can certainly help on how the car acts.

I know a few guys who used to class race fox body mustangs and they had a minimum weight limit for the class. What they did is put everything light weight on the car and added ballast since it was a class requirement and then the weight transfer would be insane. The they had the ability to put ballast where they wanted to.
Old 09-13-2011, 02:01 PM
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Actually whats new this year is the rollbar. I forgot about that. Either way Ill look into a Drag bar.

Thanks for the help
Old 09-13-2011, 08:15 PM
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Originally Posted by 355z28
Actually whats new this year is the rollbar. I forgot about that. Either way Ill look into a Drag bar.

Thanks for the help
A drag bar will do wonders for you and wont effect your drive ability unless you like to take corners really hard, but I'm guessing you dont do that to much being as you dont have your front sway bar on. Basically it will allow you to pre load one side of your suspension and plant both of your tires and keep the car strait instead of twisting and planting your right rear tire. It will keep your car strait and pick up your 60'.
Old 09-13-2011, 09:48 PM
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I went from a stock swaybar to a solid Wolfe, and the difference in the way the car leaves is unbelievable.

Before -

http://www.youtube.com/watch?v=SBV9bvEZrwM

After -

http://www.youtube.com/watch?v=SuhQkj2DCis
Old 09-14-2011, 06:28 AM
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Originally Posted by 355z28
Sound like Ill have to look into a drag bar. Its odd because I didn't have this problem last year and the only thing that has changed is I relocated my battery to the Right rear spare tire well. I would've never imagined it would throw it that far off.
The cage had some effect but that 40 lb. batter weight 300+ to the car trying to pull the nose up, now it has approximately a 40 lb. effect is the exact opposite way. So moving the battery had no less then a 340 lb. effect on how the car launches.



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