Dallas Fort Worth 5.0 Mustang Club - View Single Post - Vorshlag 2011 Mustang 5.0 GT

Fair · 08-16-2013, 05:08 PM

continued from above

A Lot Can Change In 30 Years

Some things never go out of style, but some technologies do become outdated. Brake drums are never used on performance cars anymore, but they were the standard for braking for almost 100 years. Just so, the almighty Torque Arm rear suspension has probably seen its day in the sun. Sure, this was a great aftermarket solution for 23 years of Mustang production, and it also worked well enough for 21 years on the factory F-body chassis. But what about the S197 chassis? The 5th gen Camaro? No, not so much use anymore. Ford found a way on the S197 to package a 3-link and finally added a separate Panhard Bar, and still managed to add high revving 420 hp V8 and kept the price under $29K. They could have used a torque arm, but there are just so many compromises, so they didn't.

But the aftermarket sometimes just keeps doing what it makes money at. Since a lot of what is made and offered for the S197 Mustang is coming from some of the same shops that have been developing parts for the old Fox/SN95 for almost 3 decades, some of them just take the same old solutions and apply them to the newer chassis. This is where I think the mistake lies - in what I call "aftermarket inertia". Dated engineering that doesn't necessarily work well on the latest Mustang chassis is being pushed onto people by some parts makers... that either don't know any better, or just want to make some sales. I say all this with the "In my opinion, your results may vary, blah blah blah" statement at the end.

The new for 2005 Mustang S197 chassis has a pretty decent 3-link/panhard rod rear suspension, that is light years ahead of the Fox/SN95 mess it replaced. This was and is the best handling Pony Car Ford has ever built, and part of why the 2011+ GT and Boss302 is compared in the same breath, and favorably, to $70K BMW M3s by all of the major car magazines. It was the first Mustangs in 2+ decades to not be based on the old 1977 Fairmont suspension technology. Sure, the S197's LCAs and UCA are still chock full of soft rubber bushings to allow for a smooth ride, but the fixes for these are MUCH easier than the Fox/SN95 cars. Just get some good, adjustable length LCAs with better bushings, ignore the UCA, bolt on some LCA relocation brackets, then get proper dampers and springs. Once the car is lowered you need either an adjustable Panhard rod or a Watts Link kit, to control the lateral location and re-center the axle. For 90% of the track/auto-x S197 guys out there, that's a good fit. For the last 10% at the pointy end of the racing grid, add a properly made UCA that has sphericals at both ends. Done.

I think an aftermarket Torque Arm is the wrong suspension solution for the S197 chassis. It could even make the car handle worse than stock, in some instances, possibly... no, very likely adding axle hop under braking. I haven't driven an S197 with a TA yet, so I could be wrong... but I don't think so. I've raced in too many Fox, SN95, 3rd gen and 4th gen F-bodies to believe otherwise. As a suspension designer, I understand the geometry minutiae, the Pros and Cons of a torque arm set-up. I've owned 8 different 3rd or 4th gen F-bodies, 6 Foxes, and worked on many dozens more of them over the past 20 years. So I've witnessed axle hop in these cars first hand, the clanking and banging of the aftermarket TAs, and seen the extremes needed to tame these newly added problems. I've even seen a T56 transmission housings literally EXPLODE at an autocross, after violent axle hop under braking, with the torque arm pounding into the transmission in a 4th gen F-body. BOOM! Gears and fluid and case going everywhere. I have fought with bushings and shocks and tubular Torque Arms on these cars, both my own and customer cars, and know that they make for less than ideal street cars when you "fix" most of the problems. Aftermarket TAs get very noisy, very fast.

So all that being said, I won't recommend a Torque Arm as a good solution for anyone with an S197 Mustang. Except for ONE situation: Serious, ultra-competitive SCCA autocrossers who cannot replace the LCA or use LCA relocation brackets (in ESP and STU class) but otherwise CAN run a torque arm.

Which leads us to where we are now on solid axle rear suspension rules in SCCA Solo. The rules are broken. The solid axle rear suspension rules, as currently written for SP and ST, seem to be penned by people that do not understand suspension design, or the common aftermarket solutions. So we end up where the only way to get the geometry corrected on a lowered S197 is by spending $1000++ adding a janky, last century Torque Arm rear suspension solution to a 21st century car. Again, only on a serious SCCA autocross car built for ESP or STU, that's the only time a Torque Arm on an S197 makes sense. We had even planned on making one for my 2013 GT we were gong to build for ESP, until the SCCA "re-clarified" a rule that made the class less than ideal for us to build around (and kept the rule broken for 2+ years).

For everyone else that autocrosses or tracks their car, not in SCCA's ESP or STU class, don't use this Horse and Buggy solution. That may seem negative towards the SCCA, and harsh to some aftermarket companies, and frankly it is. Because I've had to build cars around SCCA's broken and tortuous rules for 25 years. And I have seen too many useless suspension parts and poor solutions being sold by manufacturers. We go to trade shows and see that roughly 75% of the stuff there is useless CRAP. It frustrates me when I see people waste their time and money on useless crap.

We still design many of our suspension products to meet some SCCA rules, begrudgingly, but it is because some of our customers want that. It drives me nuts when a rule is written so poorly that we have to make something less than ideal to meet it, but they write the rules used by 80% of the autocross clubs in the nation. What do ya do? Until the day that another group supplants the SCCA in autocross attendance and rules making, we're all stuck with their mess of a rulebook.

I write letters to the SEB asking for rules updates and fixes. All. The. Time. It doesn't do much good, but if enough people write in and ask for these common sense updates, over enough years, they.... will.... slow...ly...fix... them. Also, given enough time, many of these old farts die off or leave the sport, and eventually some new blood with a little sense will make it onto these rules boards. I've seen a few bright, upcoming autocrossers make it onto a few committees and rules boards lately, and that is encouraging.

Here's what to ask for, if you are stuck in ESP or STU in an S197 Mustang, and want to see changes:

1. Allow alternate LCAs. Adjustable in length, tubular steel in construction, why not? You're talking under $300 in parts to fix stamped steel, floppy stock arms, all while giving you pinion adjustment.

2. Allow bolt-on, axle-side LCA relocation brackets. This $100 fix is so common and works so well that it hurts me to see them not legal in Solo (we install 2-3 sets of these on S197s per week). These make for significant fixes to rear geometry on virtually ALL solid axle RWD cars that are lowered (other than 1960s-based leaf sprung cars). Allowing these low cost, commonly available-for-every-car-in-ESP brackets that move the pick up points negate the need for $1000+ torque arm "fixes".

Those two allowances are sorely needed, as the current SCCA Solo rules for this area are at least twenty years out of date with the aftermarket and racers.

Before you ask, yes, I know some people will want to know more of the nitty-gritty details. Someone will ask for the geometry breakdown, every pro and cons, somebody else will throw three pages of calculations, another will add some vector graphics, and before you know it this will turn into an internet suspension nerdfest, heh. I think this summarizes the argument quickly: basically everything you do to help forward acceleration by adding a Torque Arm, hurts braking. Just adjusting the squat geometry ($100 LCA brackets) in a lowered S197 helps as much or more as a TA, has no down-sides, doesn't add the clanking and banging that normally comes with an aftermarket TA, and is 1/10th the cost or less. Well, other than the fact that they are not yet legal in some SCCA Solo classes. Also know that a TA is an old 1970s solution that just doesn't necessarily help the 2005-era S197 chassis 3-link rear suspension as much as it did the 1970s opposed 4-links in the Fairmont/Fox/SN95.

Cheers,

08-16-2013, 05:08 PM	#173
Fair Senior Member Join Date: Nov 2012 Posts: 333	continued from above A Lot Can Change In 30 Years Some things never go out of style, but some technologies do become outdated. Brake drums are never used on performance cars anymore, but they were the standard for braking for almost 100 years. Just so, the almighty Torque Arm rear suspension has probably seen its day in the sun. Sure, this was a great aftermarket solution for 23 years of Mustang production, and it also worked well enough for 21 years on the factory F-body chassis. But what about the S197 chassis? The 5th gen Camaro? No, not so much use anymore. Ford found a way on the S197 to package a 3-link and finally added a separate Panhard Bar, and still managed to add high revving 420 hp V8 and kept the price under $29K. They could have used a torque arm, but there are just so many compromises, so they didn't. But the aftermarket sometimes just keeps doing what it makes money at. Since a lot of what is made and offered for the S197 Mustang is coming from some of the same shops that have been developing parts for the old Fox/SN95 for almost 3 decades, some of them just take the same old solutions and apply them to the newer chassis. This is where I think the mistake lies - in what I call "aftermarket inertia". Dated engineering that doesn't necessarily work well on the latest Mustang chassis is being pushed onto people by some parts makers... that either don't know any better, or just want to make some sales. I say all this with the "In my opinion, your results may vary, blah blah blah" statement at the end. The new for 2005 Mustang S197 chassis has a pretty decent 3-link/panhard rod rear suspension, that is light years ahead of the Fox/SN95 mess it replaced. This was and is the best handling Pony Car Ford has ever built, and part of why the 2011+ GT and Boss302 is compared in the same breath, and favorably, to $70K BMW M3s by all of the major car magazines. It was the first Mustangs in 2+ decades to not be based on the old 1977 Fairmont suspension technology. Sure, the S197's LCAs and UCA are still chock full of soft rubber bushings to allow for a smooth ride, but the fixes for these are MUCH easier than the Fox/SN95 cars. Just get some good, adjustable length LCAs with better bushings, ignore the UCA, bolt on some LCA relocation brackets, then get proper dampers and springs. Once the car is lowered you need either an adjustable Panhard rod or a Watts Link kit, to control the lateral location and re-center the axle. For 90% of the track/auto-x S197 guys out there, that's a good fit. For the last 10% at the pointy end of the racing grid, add a properly made UCA that has sphericals at both ends. Done. I think an aftermarket Torque Arm is the wrong suspension solution for the S197 chassis. It could even make the car handle worse than stock, in some instances, possibly... no, very likely adding axle hop under braking. I haven't driven an S197 with a TA yet, so I could be wrong... but I don't think so. I've raced in too many Fox, SN95, 3rd gen and 4th gen F-bodies to believe otherwise. As a suspension designer, I understand the geometry minutiae, the Pros and Cons of a torque arm set-up. I've owned 8 different 3rd or 4th gen F-bodies, 6 Foxes, and worked on many dozens more of them over the past 20 years. So I've witnessed axle hop in these cars first hand, the clanking and banging of the aftermarket TAs, and seen the extremes needed to tame these newly added problems. I've even seen a T56 transmission housings literally EXPLODE at an autocross, after violent axle hop under braking, with the torque arm pounding into the transmission in a 4th gen F-body. BOOM! Gears and fluid and case going everywhere. I have fought with bushings and shocks and tubular Torque Arms on these cars, both my own and customer cars, and know that they make for less than ideal street cars when you "fix" most of the problems. Aftermarket TAs get very noisy, very fast. So all that being said, I won't recommend a Torque Arm as a good solution for anyone with an S197 Mustang. Except for ONE situation: Serious, ultra-competitive SCCA autocrossers who cannot replace the LCA or use LCA relocation brackets (in ESP and STU class) but otherwise CAN run a torque arm. Which leads us to where we are now on solid axle rear suspension rules in SCCA Solo. The rules are broken. The solid axle rear suspension rules, as currently written for SP and ST, seem to be penned by people that do not understand suspension design, or the common aftermarket solutions. So we end up where the only way to get the geometry corrected on a lowered S197 is by spending $1000++ adding a janky, last century Torque Arm rear suspension solution to a 21st century car. Again, only on a serious SCCA autocross car built for ESP or STU, that's the only time a Torque Arm on an S197 makes sense. We had even planned on making one for my 2013 GT we were gong to build for ESP, until the SCCA "re-clarified" a rule that made the class less than ideal for us to build around (and kept the rule broken for 2+ years). For everyone else that autocrosses or tracks their car, not in SCCA's ESP or STU class, don't use this Horse and Buggy solution. That may seem negative towards the SCCA, and harsh to some aftermarket companies, and frankly it is. Because I've had to build cars around SCCA's broken and tortuous rules for 25 years. And I have seen too many useless suspension parts and poor solutions being sold by manufacturers. We go to trade shows and see that roughly 75% of the stuff there is useless CRAP. It frustrates me when I see people waste their time and money on useless crap. We still design many of our suspension products to meet some SCCA rules, begrudgingly, but it is because some of our customers want that. It drives me nuts when a rule is written so poorly that we have to make something less than ideal to meet it, but they write the rules used by 80% of the autocross clubs in the nation. What do ya do? Until the day that another group supplants the SCCA in autocross attendance and rules making, we're all stuck with their mess of a rulebook. I write letters to the SEB asking for rules updates and fixes. All. The. Time. It doesn't do much good, but if enough people write in and ask for these common sense updates, over enough years, they.... will.... slow...ly...fix... them. Also, given enough time, many of these old farts die off or leave the sport, and eventually some new blood with a little sense will make it onto these rules boards. I've seen a few bright, upcoming autocrossers make it onto a few committees and rules boards lately, and that is encouraging. Here's what to ask for, if you are stuck in ESP or STU in an S197 Mustang, and want to see changes: 1. Allow alternate LCAs. Adjustable in length, tubular steel in construction, why not? You're talking under $300 in parts to fix stamped steel, floppy stock arms, all while giving you pinion adjustment. 2. Allow bolt-on, axle-side LCA relocation brackets. This $100 fix is so common and works so well that it hurts me to see them not legal in Solo (we install 2-3 sets of these on S197s per week). These make for significant fixes to rear geometry on virtually ALL solid axle RWD cars that are lowered (other than 1960s-based leaf sprung cars). Allowing these low cost, commonly available-for-every-car-in-ESP brackets that move the pick up points negate the need for $1000+ torque arm "fixes". Those two allowances are sorely needed, as the current SCCA Solo rules for this area are at least twenty years out of date with the aftermarket and racers. Before you ask, yes, I know some people will want to know more of the nitty-gritty details. Someone will ask for the geometry breakdown, every pro and cons, somebody else will throw three pages of calculations, another will add some vector graphics, and before you know it this will turn into an internet suspension nerdfest, heh. I think this summarizes the argument quickly: basically everything you do to help forward acceleration by adding a Torque Arm, hurts braking. Just adjusting the squat geometry ($100 LCA brackets) in a lowered S197 helps as much or more as a TA, has no down-sides, doesn't add the clanking and banging that normally comes with an aftermarket TA, and is 1/10th the cost or less. Well, other than the fact that they are not yet legal in some SCCA Solo classes. Also know that a TA is an old 1970s solution that just doesn't necessarily help the 2005-era S197 chassis 3-link rear suspension as much as it did the 1970s opposed 4-links in the Fairmont/Fox/SN95. Cheers, __________________ Terry Fair - Owner at Vorshlag Motorsports - www.vorshlag.com - Plano, TX Former site sponsor