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torque arm positions

Old Sep 29, 2010 | 08:46 PM
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Default torque arm positions

Okay my new crossmember has 4 holes and i was wondering how you would use each hole to tune the suspension.

like what would the car do in the top hole instead of the bottom hole? Or whats "best" for drag racing?

just something ive always wondered, same with the LCAs
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Old Sep 29, 2010 | 10:27 PM
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Originally Posted by SS4Luck
Okay my new crossmember has 4 holes and i was wondering how you would use each hole to tune the suspension.

like what would the car do in the top hole instead of the bottom hole? Or whats "best" for drag racing?

just something ive always wondered, same with the LCAs
I am wondering the samething because mine has 4 holes as well. I am pretty sure its for your instant center, but like I said I am not 100%. Hopefully somebody will chime in that really knows.
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Old Sep 30, 2010 | 01:14 AM
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think of your tq arm as just a fucked up ladder bar..it works the same..higher you go will move the center gravity back..low hp car top hole would work best..high hp car top hole would set the car on the bumper so you would move it down to stop it.
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Old Sep 30, 2010 | 07:38 AM
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And, while you are moving the bar, remember the pinion angle goes with it....
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Old Sep 30, 2010 | 08:18 AM
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What I've found, was that my car would hit the tire alot harder with it in the top hol, but then spin a little ways out, lowering the tq arm would help keep the tires planted further down track.

As for pulling the tires I've done that with the arm at the top of a BMR mount, and 1 hole from the bottom, I find that front suspension downtravel, and shock settings tend to have more of an effect on controlling this.

For a low powered car (under 450 rwhp) I'd run the arm up some, so that it will hit the tire good and get it moving. Usually there's not enough power to spin down track, providing the shock settings are right. The top hole I don't think is really needed for much other then a stock power level car, or maybe if you're trying to get a car on a 17 inch rim to hit the tire hard enough to plant it good.

Trial and error will be your best bet. Remember to adjust the pinion angle to make 1 change at a time.
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Old Sep 30, 2010 | 11:36 AM
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IF you have the UMI setup "STOCK" location is considered the 2nd set from top to bottom.
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Old Sep 30, 2010 | 10:02 PM
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Originally Posted by JL ws-6
What I've found, was that my car would hit the tire alot harder with it in the top hol, but then spin a little ways out, lowering the tq arm would help keep the tires planted further down track.

As for pulling the tires I've done that with the arm at the top of a BMR mount, and 1 hole from the bottom, I find that front suspension downtravel, and shock settings tend to have more of an effect on controlling this.

For a low powered car (under 450 rwhp) I'd run the arm up some, so that it will hit the tire good and get it moving. Usually there's not enough power to spin down track, providing the shock settings are right. The top hole I don't think is really needed for much other then a stock power level car, or maybe if you're trying to get a car on a 17 inch rim to hit the tire hard enough to plant it good.

Trial and error will be your best bet. Remember to adjust the pinion angle to make 1 change at a time.

this goes to JL and suicidal.

Im currently low 4XXwheel, like maybe 420 (im cam only MS4) and an M6. Currently the trq arm is in the very top hole and i adjjusted everything from there. My old man is worried i didnt do it right and is paying to have the local shop look it over for me while i have it in ther to be corner scaled and my trans gone through.

would this be a good setting would you say then? im running a 28" radial, but i am on a 17" rim. Car seemed to be hooking good on stock suspension when it twisted the axle in half last time at thte track though. Rear suspension will be double adj strange coilovers with 175lb springs
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Old Sep 30, 2010 | 10:47 PM
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Here is a good video how to set the torque arm.
http://www.youtube.com/watch?v=5V6gTrFHK4k
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Old Oct 1, 2010 | 04:55 AM
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If the car doesn't spin once the initial hit is made yes, if it spins down track a little I'd lower it a hole or 2.

Every car is different and track prep, etc all matters.

Everything else sounds right, check with madman on the corner weights, he knows where they should be before you go.
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