hi, i'm planning to build my own torque arm, but i have a few questions, i attached an image, this is my question, should i build the model #1 or there is a good reason to make the #2. i really don't know how the torque arm behave. please, i need answers

You'll need to do it the second way to keep it from binding as the suspension travels.

In addition to that, and from a strictly structural standpoint, you may want to do some tuning to the basic design. The upper member is under tension, and the lower member is under compression. The overall assembly is forced upward at the front. Employing the forward brace as far forward as possible will minimize deflection of the single upper member from the attachment point rearward. The longer the span from the first brace to the front mount, the more it will deflect there. Fastening the ends of the braces as close together as possible will provide the greatest rigidity, and installing a vertical brace at the extreme rear will minimize torsion on the lower member under load.

In essence, build it more like a bar joist, and deflection in both directions will be controlled better.

Some of you mechanical and structural engineers might want to chime in with the supporting math.

I know all of the aftermarket ones have the adjustable rear rods. what is the reasoning for this. does it help to realign pinion angle? can it help increase traction? just wondering if and what it is for.

They're for changing the pinion angle. Some of the aftermarket ones (like one of the Edelbrock ones, I think) aren't adjustable.

so it helps if you have your car lowered. but the adjustability would do nothing for someone who has a stock hight car.

I would depend on the sizes as to how many pieces you'd need between the upper and lower members but those pictured above are likely major overkill. You could reduce the # of connections from 5 down to 4 or 3 and the angle reduced from 45 to 30ish with no problems.

This is what I come up with a couple years ago. Pretty much based it off of a picture I found on here of Spohn's torque arm and crossmember.

Here is the arm I made:

https://www.thirdgen.org/forums/thir...orque-arm.html