Why can't a Mustang run a torque arm?

[ShadowBolt]

You can run sphericals in all 4 ends...in fact, I would recommend it over the PM3L. Call Wolfe Racecraft in Arlington who puts 1500hp through the stock design. http://www.wolferacecraft.com/detail.aspx?ID=267 I think their claim to fame is 7's on the stock 4 link. Since bushings are open, install a heim in the stock UCA and go to town. You are going to get a TON of gear noise and you will need to up your rear spring rates to account for the lack of bind but the PM3L guys are already doing that.

You guys are over thinking this and just need to run the right bushing setup that isn't overtaxing half of the stock design and just gusset the pickup point as the CMC rules may allow. Problem solved and you keep $750 in your pocket.

This is a drag car and what does that have to do with a road racing car? Also I only see the bushing for the axle end. They sell another one designed for the chassis end?

JJ

[RichardP]

You can run sphericals in all 4 ends...in fact, I would recommend it over the PM3L. Call Wolfe Racecraft in Arlington who puts 1500hp through the stock design. http://www.wolferacecraft.com/detail.aspx?ID=267 I think their claim to fame is 7's on the stock 4 link. Since bushings are open, install a heim in the stock UCA and go to town.

What! Of course it works for drag racing. That's not what we are doing. Going around a corner is what puts the 4 link into a bind and tears things up. It's been proven that the spring rate has to go down because most of the roll rate is from bending the chassis mounts around (until they fail).


Richard P.

[RichardP]

Ford Racing (and Ford) stopped producing these so the only place I can find them are Maximum Motorsports at $200.00 a set!

If they are not being made, the fact that one vendor still has a stash of them (and prices them accordingly) just means that the issue gets kicked down the road a bit...

Richard P.

[ShadowBolt]

If they are not being made, the fact that one vendor still has a stash of them (and prices them accordingly) just means that the issue gets kicked down the road a bit...

Richard P.

Just placed an order at $240.00 for a set delivered to Hutto, TX.

JJ

[RichardP]

I think we generally expect too much of these platforms.

This would be the key. None of the problems being discussed are inherent to four links, three links, or torque arms. We are just abusing these cars way beyond their original design and the rules severely limit what can be done to reinforce the problem areas. It wouldn't be unreasonable to believe that the change from CMC1 to CMC2 power, along with heavier wheel and tire packages, is exacerbating the problem.

I would be OK with allowing properly mounted, sufficiently stiff torque arms on both Mustangs and Camaros. I also see that as a pretty big step outside the concept of CMC. Glad I'm not making the decisions...


Richard P.

[BADVENM]

Interesting that we're mentioning doing things in these cars they werent designed for.

My first event this year in the Fox was filled will moans, groans, what I thought was rubbing/grinding etc with the same shock/suspension setup I had last year in CMC1. This was generally in hard/sharp turns...mostly right. I turned the shocks to full firm and alleviated 70% of the groaning noise. I thought for sure something in the transmission tunnel area was rubbing or grinding against something else. We couldnt find anything that would support that idea.

Seems as if the chassis was possibly flexing and doing things with CMC2 power, bigger for me (not 4 piston) brakes and just overall harder running of the car compared to last year. I still get the un-nerving noises at times but nothing since the first event.

[marshall_mosty]

If you look at the combination of 4 arms, not parallel to each other, 2 with different lengths from the other 2, and then lift one side and drop the other, arc lengths do nothing but get all crazy... Even with a T/A and only running lower control arms, you still have an arc length change between the two arms that will introduce a itsy bitsy amount of rear end steer, as one wheel will move forward or aft and the other the opposite direction (unless you compress and droop the exact same amount from the parallel reference point of the lower control arm to the ground)... Okay, enough nerd stuff.

This $hit's complicated. It sucks. There is no "magic bullet". There are drawbacks to longer T/A's (poor forward bite). There are advantages (less brake torque to cause axle hop). However, the 4th gen has a shorter torque arm than the Mustang replacement (Griggs or MM) and so are more prone to brake hop. The 3-link (real or “poor man’s”) will have better bite than a MM or Griggs T/A since the instant center will allow for more anti-squat (depending on the angle of the arms).

Unbalanced Engineering has done a decent “Freshman level” writeup on their decoupled torque arm.
http://www.unbalancedengineering.com...rque%20Arm.pdf

[mitchntx]

This would be the key. None of the problems being discussed are inherent to four links, three links, or torque arms. We are just abusing these cars way beyond their original design and the rules severely limit what can be done to reinforce the problem areas. It wouldn't be unreasonable to believe that the change from CMC1 to CMC2 power, along with heavier wheel and tire packages, is exacerbating the problem.

I think the bigger problem is the person behind the wheel.
Every year the bar gets raised higher and higher.
Lap times have steadily dropped.

Learning minute nuances of the tracks, how the platform of choice responds to 1/2 lb of air pressure and race
craft has created more and more loading being placed on ANY platform.

Example:
Lap times are the reason tires don't last as long as they used to ... not compound.
Its to the point where tenths seperate drivers and circumstances play a bigger and bigger role.

If you want CMC to get back to where it was 3 years ago ... leave the freaking rules alone.
No one wants to jump into a series with the rules in such turmoil as witnessed over the last couple years.

[Rob Liebbe]

How about the Steeda 5-Link? This setup essentailly replaces the upper arms with longer and parallel units, comes with a panhard bar for lateral control. Should be better designed for the rigors of racing. Half the price of big brakes. There is adjustability, but you find your setting and weld up any adjustment holes or slots.

http://www.steeda.com/store/steeda-5...d-mustang.html

[RichardP]

How about the Steeda 5-Link? This setup essentailly replaces the upper arms with longer and parallel units, comes with a panhard bar for lateral control. Should be better designed for the rigors of racing. Half the price of big brakes. There is adjustability, but you find your setting and weld up any adjustment holes or slots.

http://www.steeda.com/store/steeda-5...d-mustang.html

The 5-link hardware isn't too bad (other than being incorrectly named). On the other hand, I would run it with the left side link missing. Better geometry than the PM3L...


Richard P.