[ReverendDexter]

Finally got the last piece of my torque arm setup in this week, and had autocross today.

The difference is AMAZING. Where it used to be the ass end would get sketchy and you'd have to back out of it 'til it settled down, now I just punch it and it squats and GOES.

Seriously, the 4-link is trash. No one who can afford not to should ever run it.

[bandity2k00]

Any links to your setup? What do you think about it for drag racing? Sounds like it would help my car hook if it squats real good

[Ryguy33]

pics?

[ReverendDexter]

I'm using the full Maximum Motorsports setup; I can get some pics later, but don't have any right now.

I'm not sure how it would do for drag racing. The geometry is definitely much, much better than the stock 4-link, but I'm not sure how it compares to a proper set up with good adjustable UCAs. The other issue is that torque arms are only good to so much power, so if you're boosted, it may not hold up. On the flip-side, when it squats with the torque arm, that's 100% due to weight transfer, unlike the quadrabind where some significant amount of the squat you see is actually due to axle-wrap acting on the UCAs and lifting the axle up into the chassis.

[v606er]

Nice!



Oh, +1 to nudepics.

[Jazzer The Cat]

So you guys did run yesterday.

Elizabeth and I showed up and I was NOT feeling well and was on/off drizzling from 7:30~8:00 or so when we left. My head was real fuzzy and actually forgot my drivers license anyway, so we bailed. It is just as well, as I wouild not have been comfortable pushing my ride being sick. I took the day off today and been sick as a dog all day

Congrats and see you next month

Jazzer

[Serlin]

Glad you like yours.
I love mine too!
What springs are you running? I'm using H&R Super Race Springs all around.
1000 lbs up front and 350 in the rear (I think)

But ya, on the road course, I'm able to get on full throttle in the apex and hold flat out exiting most turns.

I also have a T2R rear diff. That helps a lot! Especially on an autox track.

Cool!

[ReverendDexter]

Maximum motorsports road & track springs up front with MM torque arm springs out back. The TA springs are a lot higher rate than normal rear springs, but I honestly don't know the rates.

[ReverendDexter]

Jaz - You're probably glad you left, it was PCA insurance again, so no passengers. And I won't be out there next month, as it conflicts with something the wife's doing so I need to stay home and watch the kid.

Good news is that PCA is doing a mini-enduro event on the 2nd. Morning runs are single laps, but in the afternoon you get all four of your laps at once. Sounds like fun

Oh, and I'll get some pics when I swap my street tires back on either this afternoon or tomorrow.

[Jazzer The Cat]

I have worked out the PCA insurance deal, so I can have a passenger

I won't be able to attend an event on the 2nd, as the "to be" and I are heading to Disneyland for 5 days and then to Universal Studios for another 2 days.... life is good (other than being sick )

Jazzer

[Trick Tuners]

I too was amazed with the TQ arm performance, but then i did the entire max grip box at the same time. I have yet to let the back end hang out. Each time i push it a bit harder it just grips and goes. I still have that "fear" of doing 180s when hammering it in the corner so i'm pushing it a bit harder each time. The braking performance with the tq arm is crazy too! no more nose dive!

[ReverendDexter]

Mine's similar, but my exhaust is dumped, I'm not running COs, and I have the stock rear sway bar.

[force-fed-snake]

Originally Posted by ReverendDexter it squats

does it actually squat, or is this just a seat of the pants type feel?

im only bringing this up for conversation sake... i am by no means an expert, although i do have a fairly good grasp of whats goin on in chassis dynamics.

the way i see a proper set-up t/a working would infact lift the car on hard acceleration, and pull down on the car with brake torque. the t/a systems can get better svsa when compared to a 3-link, which give a slight advantage under braking and the flip side a 3 link can usually come up with better a/s for accelleration.

so back to the point, if the car does in fact have a serious "squat" goin on, i would find myself wondering why, and if there is indeed more performance to be found by tuning the system.

like i said...only for conversation sake, im still tryin to decide which system (t/a or 3 link) is gonna be my winter fab project.

[ReverendDexter]

Originally Posted by force-fed-snake does it actually squat, or is this just a seat of the pants type feel? im only bringing this up for conversation sake... i am by no means an expert, although i do have a fairly good grasp of whats goin on in chassis dynamics.

Squat here I wasn't using in the full literal sense. I was meaning that you mash the gas, and the rear end instantly settles down and you go forward. No side-to-side action, no more "skittering", just plant and go. I'd have to see video to see if there's squat per the drag racer's def.

Originally Posted by force-fed-snake the way i see a proper set-up t/a working would infact lift the car on hard acceleration, and pull down on the car with brake torque. the t/a systems can get better svsa when compared to a 3-link, which give a slight advantage under braking and the flip side a 3 link can usually come up with better a/s for accelleration.

That's backwards from all the setups I've ever seen. TAs have a static IC that's setup for better acceleration, 3-links have a mobile IC that gives them better braking.

For the car to lift on acceleration you'd have to have over 100% anti-squat. While (I believe) you could certainly design your setup to be like that, none of the out-of-the-box units do.

Originally Posted by force-fed-snake so back to the point, if the car does in fact have a serious "squat" goin on, i would find myself wondering why, and if there is indeed more performance to be found by tuning the system.

Not much tuning to be had, other than maybe to raise my roll center via adjusting the panhard bar or changing the spring/roll rates. There's nothing that would change anti-squat/anti-dive.

Originally Posted by force-fed-snake like i said...only for conversation sake, im still tryin to decide which system (t/a or 3 link) is gonna be my winter fab project.

For whatever it's worth, the TA is still the dominant force in American Iron/AIX where suspension is pretty much open (other than I think you can't run IRS unless the car came with it, but I'm not 100% on that as MM has an IRS foxbody). If there was a faster setup out there, I would think that by now most people would've swapped to it.

Either way it's gonna be a performance improvement over the quadrabind in every measureable way.

[Trick Tuners]

My understanding is that the squat ratio is controlled by the position of the lower control arm on the axle side, and not the TQ arm. You could raise or lower that point to add more squat or anti squat. This is assuming that you already have the TQ arm and does not apply to 4 link vs TQ arm.

[ReverendDexter]

Originally Posted by Trick Tuners My understanding is that the squat ratio is controlled by the position of the lower control arm on the axle side, and not the TQ arm. You could raise or lower that point to add more squat or anti squat. This is assuming that you already have the TQ arm and does not apply to 4 link vs TQ arm.

Well, it's determined by the point of intersection (instant center or IC) as determined by drawing straight lines through the control arm pickup points.



So, by lowering the control arm pickup point on the axle side, you change the angle of the control arm such that that IC is moved rearward and upward, which would certainly increase anti-squat, but there's nothing that says that's the only way to increase it.

EDIT: Here's an image for the TA:

http://www.rossautoracing.com/antisquat.html

As you can see there, the anti-squat is determined by the location of the leading end of the TA; near as I know it has nothing to do with the LCAs.

[Trick Tuners]

Originally Posted by ReverendDexter So, by lowering the control arm pickup point on the axle side, you change the angle of the control arm such that that IC is moved rearward and upward, which would certainly increase anti-squat, but there's nothing that says that's the only way to increase it. EDIT: Here's an image for the TA: As you can see there, the anti-squat is determined by the location of the leading end of the TA; near as I know it has nothing to do with the LCAs.

I agree with the statement on top, and that you could also alter the position of the rear control arm chassis mount, but that would require much more modifications than altering the rear point. The TA calculation does not provide an input for the TQ arm position. It only has.
Radius of the Tire (Rt)
Length of Torque Arm (Lta)
Center of Gravity Height (Cgh)
Wheel Base (Wb)

The length of the TQ arm is not "adjustable" so that is fixed on our cars. I know on a jeep suspension with a TQ arm that they have you redrill the lower control arm mounting points a bit lower to alter the squat behavior.

[ReverendDexter]

Well, the position of the torque arm is taken into consideration by the way they're defining the length not as the length of the TA itself, but the distance between the centerline of the rear axle and the leading pickup point.

[Trick Tuners]

Originally Posted by ReverendDexter Well, the position of the torque arm is taken into consideration by the way they're defining the length not as the length of the TA itself, but the distance between the centerline of the rear axle and the leading pickup point.

True, but think about the difference in that measurement when you rotate the TQ arm. It will be in the sub 1/16" range as far as that measurement goes. There is really very little possible adjustment for the "height" of the TA arm chassis mount. I would call that a "fixed" variable on the mustang.

[ReverendDexter]

Originally Posted by Trick Tuners True, but think about the difference in that measurement when you rotate the TQ arm. It will be in the sub 1/16" range as far as that measurement goes. There is really very little possible adjustment for the "height" of the TA arm chassis mount. I would call that a "fixed" variable on the mustang.

You're confusing theory with application. In the theory, a torque arm could rest at any angle from flat to almost vertical. With that much change of angle, the effective length of the TA is anything from 100% of it's actual length down to 10% or less.

I agree that the torque arm mount point is fixed when we're talking about an existing/installed unit. The point can be moved when you're designing one though, and built to create a different anti-squat percentage as desired (within the limits of the geometry of the other control arms, location of other necessary components, etc).