Just had a thought!

[Vimy101]

^^ Except Road and Track & Car and Driver both complaining as compared to similiar cars the spec B had noticablely more body roll. I'm used to driving german stuff which all corner pretty flat. My spec B doesn't roll nearly as much as some of my past cars, but it still is more then should for a car that is supposed to have a "sport tuned" suspension.

 

Your Spec. is also very different than the other cars tested in that one famous comparison. It has the flat four and symetrical AWD and thus has a lower COG than those other cars with their high mounted I or V configurations. It doesn't have to be as stiff feeling because it doesn't have as much roll potential. You will also recall that the Spec.B was the fastest car around their test track. You are still a Spec.B noob and getting used to your unconventional car. Live with it for a while and you will be impressed with how well it does just about everything from freeway cruising to twisties. (I took mine out for a serious run to the donut shop the other night during our first decent snow. Effing fantastic! )

[psi365]

^^ Yes due to the engine being a flat 4 it will have a lower COG, however I've driven more then a different varieties of cars in the snow. How many 911 twin turbo have you driven in the snow let alone on dry pavement? That's got a flat six in it and I've driven several dozen. Porsche also uses a viscous coupler just like Subaru does in the LGT. However if you ever do drive one you'll instantly notice you get next to zero body roll in turns. Now being the fact that I've been an Audi tech for almost 9 years now I have more then enough experience with cars that can actually handle fairly well from the factory. Even A3's don't exhibit nearly as much body roll as my car does. The Spec B may have been the fastest, however all the drivers involved all claimed the car had a lot more body roll and these are all experts who's job it is to test many different cars. So are you telling me that your vast knowledge is greater then most of the people on here, my 11 years + of being a /Master Guild Audi tech/ASE master Guild/Porsche certified/Chrysler certified/GM certified, and professional car writers??

 

Seriously if you think the spec B is the best car ever you really need to drive some more cars.

[Vimy101]

^ The Porche is not a GT and the Spec.B is not an autobahn monster. They are completely different ideas. One is a four banger and the other is a 6. One costs at least twice as much as the other. One is a sedan the other is a coupe.

 

The experts spent a few days with the Spec.B. Learn your car and you will be amazed at just how well it does many, many things. All that body roll and the Spec.B still spanked the competion around their test track. It's a true GT not a true sportscar.

 

FWIW, I love Porsches (how could anyone not?) but they never even entered my choice options first, because of daily functionality and secondly, because of maintenance.

[IwannaSportSedan]

You are still a Spec.B noob and getting used to your unconventional car.

 

Perhaps you should refrain from calling people things... Posers and noobs... You seem to be wrong more often than right, when you try to classify the people you are talking to.

 

Live with it for a while and you will be impressed with how well it does just about everything from freeway cruising to twisties. (I took mine out for a serious run to the donut shop the other night during our first decent snow. Effing fantastic! )

 

No one here is saying that the Spec B isn't a nice car that does well for itself. Fantastic and Impressive is apt. I think that about my GT Limited.

 

But I am not dilusional to think that it is the best car being built, in it's class, or even the best it could be. There is more potential there. Clamoring for more does not automatically mean disparagement to the current state of Legacys.

 

I've said that it could do even better with better equipment and setup. Current setup is fantastic and impressive... but STI springs and JDM 20mm rear sway bars (both products offered BY SUBARU in other markets) would probably make it better, and lower. (if lower CG of the engine is good, then how is high ride-height, which affects overall CG, good for handling?)

 

By the way, Springs can be preloaded. Dampers not so much. Dampers will find their resting position by shuttling oil through their valving, and resist quick movements from that baseline. And I doubt that even the JDM rear sway bar, which is thicker than the US market part, won't effect the ride quality much at all, in terms of damping quality, but will make a difference with rear body roll.

 

Not only that, but a lower overall CG (on lower-riding cars) resists roll even more than a higher one. the CG being below the axle centerlines uses the car's weight to resist roll, and even pitch a bit. if the CG gets near or above the axle centerline, and above the suspension geometry, it acts as more of an inertia driven lever to compress the suspension. That is why SUVs roll so easily, A lot of weight levering over the suspension.

 

As a kiddie-analogy... Is/was it easier to tip a traditional tricycle, or a big-wheel? the CG of a big-wheel is much lower, because you sit much lower. Unfortunately for Big-wheels, it negatively affected traction due to huge rear weight bias, and hard plastic tires. Tricycle seats are up high, and it is much easier to tip over, both having an inherently unstable three-wheel layout. The general principal applies to cars, too, though. The leverage of high CG is physics, a game that cars have to play, too.

 

I am not saying that the stock spec B is a tricycle compared to a lowered GT like mine. The difference isn't nearly that pronounced. But if stock Spec B is good, lowered spec B with well chosen sway bars could very logically be better, not worse or indifferent.

 

I'd love to hear from someone who has fitted Ion progressive-rate springs, and cusco or similar swaybars to their spec b, before and after. I'll bet after is better, without much of a ride-quality loss. (heck, I'd love to mod my car with those parts and bilsteins, if I had the money... probably a slightly larger difference between before and after, considering the stock US-market GT dampers and swaybars on my car.)

 

Keep in mind that Subaru also tunes for the lowest-common denominator buying the car. They don't want someone coming in and complaining about the harshness of the ride of their new Subaru, so they will tune it softer for a nicer ride than the most optimized handling/ride tradeoff setup. That is why the Aftermarket exists, and is profitable. They can offer real benefits through optimized parts.

 

Personally, I wouldn't mind Subaru leaving the Spec B mostly as is, and dropping the price on both the GT Limited and the Spec B. For the $34.9K, it should be a Legacy STI, with the specs similar to the WRX STI, for the reasons that I have illustrated time after time.

 

The Spec B would be even more impressive, due to being a better value, at 30-31k, with full color options, and building as many as demand dictates.

 

If they are going to build 500 ~$35k limited edition turbo Legacys, and try to sell them on the same lot as the 08+ WRX STI for the same price, it should be equipped the same way. And the equipment will make the Legacy an even better yet grand touring Sport Sedan, and in those numbers, it won't eclipse the WRX STI as a sport compact rally-replica. Plus, even you, Vimy, referenced the Legacy's rally-bred past, so it isn't such a stretch.

 

And you keep throwing up the Grand Touring flag... do you know what that means, where the rubber meets the road? Grand touring is squarely between touring, which is pillowy and comfortable with some amenities, but not sporty. and Sport, which is hard-focused and not very concerned with comfort aside from being comfortable enough to drive well, in some instances nearly Race-ready, for the road.

 

A GT requires an element of sport. And MORE of that, in the Spec B's case, would not be a bad thing, nor negate it's role as a grand tourer. A bit more performance is not going to make the car drastically less capable or practical. half an inch to an inch less ride height isn't going to make the Spec B into some track-monster that is incapable of being tolerated on a daily commute.

 

The Porsche 911 Turbo is a grand touring coupe. (So is the Vantage, and even cars like the 599 GTB Ferrari, or cars closer, like the G37. Two doors does not automatically mean "sportscar".) especially compared to the GT3 and GT2, and even Cayman S, which are more focused, and closer to the term "sportscar."

 

Granted it is more expensive than a Legacy, but there are many things in common, and the laws of physics apply to both in exactly the same ways, regardless of practicality or maintenance concerns. The Legacy shares traits in common, coincidently, with the Porsche more than just about any other unrelated cars share traits with each other. Powerful-output engines in Boxer-configuration, turbocharged, and AWD. Granted, they are at different levels, but what other cars share ALL of those four character traits, besides Porsche, and Subaru's lineup, even though not all porsches are AWD, and almost all Subarus are. (except some japanese/euro market microcars)

 

I do think it is increasingly dubious for you to continue to tell PSI that he is somehow inferior and needs to learn more. He sounds pretty well informed and experienced to me.

 

PSI isn't saying that the Spec B is incompetent. He is saying that it isn't the pinnacle of the automotive industry, which is what you seem to be getting at, by blindly praising the Spec B, seemingly without any objectivity. Being proud of your car is one thing... you seem to be bordering on un-reality.

[SLegacy99]

[Vimy101]

Perhaps you should refrain from calling people things... Posers and noobs... You seem to be wrong more often than right, when you try to classify the people you are talking to.

 

 

 

No one here is saying that the Spec B isn't a nice car that does well for itself. Fantastic and Impressive is apt. I think that about my GT Limited.

 

But I am not dilusional to think that it is the best car being built, in it's class, or even the best it could be. There is more potential there. Clamoring for more does not automatically mean disparagement to the current state of Legacys.

 

I've said that it could do even better with better equipment and setup. Current setup is fantastic and impressive... but STI springs and JDM 20mm rear sway bars (both products offered BY SUBARU in other markets) would probably make it better, and lower. (if lower CG of the engine is good, then how is high ride-height, which affects overall CG, good for handling?)

 

By the way, Springs can be preloaded. Dampers not so much. Dampers will find their resting position by shuttling oil through their valving, and resist quick movements from that baseline. And I doubt that even the JDM rear sway bar, which is thicker than the US market part, won't effect the ride quality much at all, in terms of damping quality, but will make a difference with rear body roll.

 

Not only that, but a lower overall CG (on lower-riding cars) resists roll even more than a higher one. the CG being below the axle centerlines uses the car's weight to resist roll, and even pitch a bit. if the CG gets near or above the axle centerline, and above the suspension geometry, it acts as more of an inertia driven lever to compress the suspension. That is why SUVs roll so easily, A lot of weight levering over the suspension.

 

As a kiddie-analogy... Is/was it easier to tip a traditional tricycle, or a big-wheel? the CG of a big-wheel is much lower, because you sit much lower. Unfortunately for Big-wheels, it negatively affected traction due to huge rear weight bias, and hard plastic tires. Tricycle seats are up high, and it is much easier to tip over, both having an inherently unstable three-wheel layout. The general principal applies to cars, too, though. The leverage of high CG is physics, a game that cars have to play, too.

 

I am not saying that the stock spec B is a tricycle compared to a lowered GT like mine. The difference isn't nearly that pronounced. But if stock Spec B is good, lowered spec B with well chosen sway bars could very logically be better, not worse or indifferent.

 

I'd love to hear from someone who has fitted Ion progressive-rate springs, and cusco or similar swaybars to their spec b, before and after. I'll bet after is better, without much of a ride-quality loss. (heck, I'd love to mod my car with those parts and bilsteins, if I had the money... probably a slightly larger difference between before and after, considering the stock US-market GT dampers and swaybars on my car.)

 

Keep in mind that Subaru also tunes for the lowest-common denominator buying the car. They don't want someone coming in and complaining about the harshness of the ride of their new Subaru, so they will tune it softer for a nicer ride than the most optimized handling/ride tradeoff setup. That is why the Aftermarket exists, and is profitable. They can offer real benefits through optimized parts.

 

Personally, I wouldn't mind Subaru leaving the Spec B mostly as is, and dropping the price on both the GT Limited and the Spec B. For the $34.9K, it should be a Legacy STI, with the specs similar to the WRX STI, for the reasons that I have illustrated time after time.

 

The Spec B would be even more impressive, due to being a better value, at 30-31k, with full color options, and building as many as demand dictates.

 

If they are going to build 500 ~$35k limited edition turbo Legacys, and try to sell them on the same lot as the 08+ WRX STI for the same price, it should be equipped the same way. And the equipment will make the Legacy an even better yet grand touring Sport Sedan, and in those numbers, it won't eclipse the WRX STI as a sport compact rally-replica. Plus, even you, Vimy, referenced the Legacy's rally-bred past, so it isn't such a stretch.

 

And you keep throwing up the Grand Touring flag... do you know what that means, where the rubber meets the road? Grand touring is squarely between touring, which is pillowy and comfortable with some amenities, but not sporty. and Sport, which is hard-focused and not very concerned with comfort aside from being comfortable enough to drive well, in some instances nearly Race-ready, for the road.

 

A GT requires an element of sport. And MORE of that, in the Spec B's case, would not be a bad thing, nor negate it's role as a grand tourer. A bit more performance is not going to make the car drastically less capable or practical. half an inch to an inch less ride height isn't going to make the Spec B into some track-monster that is incapable of being tolerated on a daily commute.

 

The Porsche 911 Turbo is a grand touring coupe. (So is the Vantage, and even cars like the 599 GTB Ferrari, or cars closer, like the G37. Two doors does not automatically mean "sportscar".) especially compared to the GT3 and GT2, and even Cayman S, which are more focused, and closer to the term "sportscar."

 

Granted it is more expensive than a Legacy, but there are many things in common, and the laws of physics apply to both in exactly the same ways, regardless of practicality or maintenance concerns. The Legacy shares traits in common, coincidently, with the Porsche more than just about any other unrelated cars share traits with each other. Powerful-output engines in Boxer-configuration, turbocharged, and AWD. Granted, they are at different levels, but what other cars share ALL of those four character traits, besides Porsche, and Subaru's lineup, even though not all porsches are AWD, and almost all Subarus are. (except some japanese/euro market microcars)

 

I do think it is increasingly dubious for you to continue to tell PSI that he is somehow inferior and needs to learn more. He sounds pretty well informed and experienced to me.

 

PSI isn't saying that the Spec B is incompetent. He is saying that it isn't the pinnacle of the automotive industry, which is what you seem to be getting at, by blindly praising the Spec B, seemingly without any objectivity. Being proud of your car is one thing... you seem to be bordering on un-reality.

 

I agree with pretty much everythng you write. You want to mod your car? Great! Go for it. I just think the Spec. is an excellent GT right out of the box created by excellent, experienced engineers with big budgets (or at least much bigger than yours).

 

Yes, OEM cars are designed for a broad market. You want to mod yours into a kidney puncher that has trouble with speed bumps and throws you off the road when you encounter potholes? Go for it.

 

When I refer to a brand new Spec. owner as a noob it is not a term of derision. It merely refers to the fact that he hasn't lived with the car for 40k miles.

 

BTW, there is nothing wrong with a little intial weight transfer. Adding stiffer rear sways takes away from the benefits of having a very good OEM independent suspension. It's all about some level compromise and a good GT should be able to do most things well. The Spec.B does just that. Would an OEM Spec.B be as glued to a track as your lowerd LGT? Probably not but the Spec. would probably be better on a washboard gravel road and many or the crapped out, beaten up Chicagoland roads.

[IwannaSportSedan]

I agree with pretty much everythng you write. You want to mod your car? Great! Go for it. I just think the Spec. is an excellent GT right out of the box created by excellent, experienced engineers with big budgets (or at least much bigger than yours). [/Quote]

 

Subaru's engineers are obviously quite good... as for their budget, and their final say on specifications, I don't know. Bean-counters have their ways, too.

 

Yes, OEM cars are designed for a broad market. You want to mod yours into a kidney puncher that has trouble with speed bumps and throws you off the road when you encounter potholes? Go for it.

 

You don't seem to be getting it. My modded car, and most of them on this forum, are not like that. Last month, I put more than 2000 miles on my car. From central Iowa to Ann Arbor, MI, through Chicago. Ann Arbor, and most of central Michigan is famous for rough roads, and Iowa isn't much better. My car is not a kidney puncher by any means, and I doubt it would be with further well-chosen modifications.

 

My whole point is, that better handling than stock can be had, with little or no detriment to ride quality. It just won't be quite as pillowy-soft.

 

When I refer to a brand new Spec. owner as a noob it is not a term of derision. It merely refers to the fact that he hasn't lived with the car for 40k miles.

 

When you call anyone a noob with the condescending tone you used, it is a derision. Even after he laid his qualifications plain, you called him that again. It is disrespectful, just as calling people posers, just because they have opinions, backed up by facts, different than yours. The Spec B performs how the spec B performs, and it does not take 40k miles to figure that out. it probably doesn't even take 4k miles.

 

Subarus, especially the Legacy are very easy and simple to drive well, with few major behavioral vices, which is actually a distinct benefit. But, again, there is more potential there for even better performance without much of any drawback. Subaru is leaving that potential on the table, without actually using it, and putting it in the car from the showroom.

 

BTW, there is nothing wrong with a little intial weight transfer. Adding stiffer rear sways takes away from the benefits of having a very good OEM independent suspension. It's all about some level compromise and a good GT should be able to do most things well. The Spec.B does just that. Would an OEM Spec.B be as glued to a track as your lowerd LGT? Probably not but the Spec. would probably be better on a washboard gravel road and many or the crapped out, beaten up Chicagoland roads.

 

Pretty much every independent suspension ever devised uses anti-roll devices. It hardly deminishes the independent nature of the suspension to tighten it up a fraction for a more stable roll-behavior. Like I said. Subaru puts better rear roll bars on the JDM GTs than any Legacy, Spec B included, gets in the US. The Subaru engineer argument is out the window, because subaru engineers chose both, and chose to offer the softer version here, even on the Spec B.

 

Anti-roll devices are specifically engineered to allow independent movement of one side of the axle (with jointed linkages, usually), when an event affects only that side's wheel. It does come more into play when the whole suspension is working together in a maneuver that effects both sides of the suspension.

 

There is a reason that the anti-roll bars are attached to the chassis at two points, and each end of the anti roll bar has linkages with two swivel joints each. each side of the suspension, if moving independently, just moves the linkages on their joints, and the car stays level, because it was just a bump, or a dip, or a pavement imperfection under one or the other tire.

 

But when inertia tries to counter the change in direction of forward motion, (pushing the car sideways in the vector of the previous forward motion, as the car changes it's forward direction, or "turning") it rolls onto it's outside suspension, and lifts it's inside suspension, and the chassis doesn't stay level.

 

The torsion quality of the anti-roll bar resists this, and the bar, being firmly attached to the chassis resists the outside compression, and leverages that against the chassis mounts and inside suspension, which is being unloaded, adding the torsion resistance of the bar to the low side spring's compression resistance, counteracting the car's inertia, and putting that energy through the tires, rather than into the suspension. Without that anti-roll torsion addition, the springs would have to be extra hard and ride very rough, otherwise, the body roll would lift the inside wheels of the ground to the point of rolling the car over.

 

If the tires are good, and have lots of traction, they resist lateral sliding, and all that inertia is preserved until the car is no longer turning, and continues straight forward. A good anti-roll bar does nothing to truly impede independent suspension action under rough surface conditions, if the linkages are designed correctly. Even when countering body roll, the linkages still allow some independent wheel movement.

 

And lateral weight transfer in handling is wasted energy, and it limits suspension travel over imperfections in the surface. It can actually hurt the ride quality, if it allows too much roll. (I am not saying that the Legacy suspension is that bad...)

 

If a car is leaning on it's suspension due to body roll, one side is low, and one side is high. The low side has lessened capacity to deal with bumps, due to already being compressed, and the high side is more likely to lose traction over dips, due to being already extended. Lateral kinetic energy is being used to compress the low side springs and twist the sway bars, rather than being maintained and put into the traction patches of the tires. Anti-roll bars provide a selective torsion that allows the car to use less than rock-hard springs, and allows the spring and damper to work on one wheel, while the anti-roll bar coordinates the motion of the chassis over the axle as a whole.

 

And it also hurts suspension transition times, if the car has to change direction, like a slalom course. Kinetic energy being absorbed into the suspension, and motion of the rolling of the chassis is wasted, and the motion has to be counteracted with additional energy in the opposite direction, to change direction of the vehicle. Lateral weight transfer does hurt handling performance.

 

The only time weight transfer is really desired is a bit of squat on acceleration (weight transfer to rear, for better traction) and a bit of dive on the brakes, (weight transfer to front, for better braking traction) And that is fine, because there are no anti-dive systems linking the front and rear wheels together, only anti-roll bars linking one side to the other on each axle, which only affects lateral roll, not dive-squat. Spring rates handle that.

 

I don't have time or money to race my Legacy, it is my daily driver. It isn't a track car for me. It is lowered because it decreases frontal drag, lowers the center of gravity, decreases body roll, and also looks better. I'll admit it.

But the benefits are not imagined, and the detriments you seem to think would happen, aren't.

 

In November, for thanksgiving, I drove all over some of the most wash-board gravel roads in eastern Iowa that most rural people would see. No problems. My wife was napping in the passenger seat, and wasn't disturbed in the least. Maybe not as 'glidingly" as your spec B, but certainly not any kind of a problem at all, and the car was completely controlled over the road surface. And with the improvements, it handles better on tarmac than stock, so I am not seeing a downside, yet you claim there should be.

[Vimy101]

^ Lighten up and happy motoring.

 

BTW, heavier sways take away from independently acting suspension. Motoring 101. It in effect joins the one strut and spring to the other. One gets compressed and the other gets compressed and the heavier you go the more it will transfer irregularities from one wheel to the other.

[IwannaSportSedan]

Anti-roll bars aren't pushrods, they are torsion springs. And the jointed linkages prevent most of what you just described.

 

You need to move beyond 100-level theory.

[Vimy101]

^ Sigh... Sway bars impart more irregularities from one side to the other by compressing the unloaded side thus reducing "sway". The stiffer the tortion spring the more the other side is going to feel it. This isn't a difficult concept.

[IwannaSportSedan]

Go back and re-read post 33.

 

Read it closely. Read it a couple of times.

 

Anti-roll bars leverage each side of the suspension mostly against the chassis, less so the suspension against itself from side to side, and only when the whole chassis is involved.

 

And irregularities, as you call them, are within the range of motion of the anti-roll bar linkages, which are on two pivot pins, and move independently. that allows quick independent movements not to be transferred into the bar itself, it's chassis mounts, or the other side of the suspension.

 

The torsion bar only applies resistance to the suspension when the chassis is being rolled over by inertia, and the whole suspension system is in play, and the chassis takes up the movement in the linkage, and applies torsion spring resistance.

 

If only one wheel, and any one given instant is being affected by an "irregularity", up or down, the linkage on that side swivels on it's bolt-pins, or bushing joints in other designs, and the coil spring, strut and control arms for that wheel do their business for that event, independently of the rest of the suspension. It is not transferred to the other side of the axle. At least not on a modern suspension like the Legacy and most other current cars have. The bars aren't bolted straight to the control arms, and don't work as if they were.

 

And if both sides go up or down at the same time, the sway bar swivels in it's chassis mounts, and has no effect.

 

The only time an anti roll bar adds resistance is when the whole chassis "leans" on one side of the suspension, which is exactly what it is meant to do. Hollow bars have different rates than solid and diameter makes a rate difference as well, which tunes how much resistance it imparts, such as the US model having ~16mm rear bars, and JDM models having 20mm diameter bars. (IIRC)

But it still only works when the chassis rolls, not for "irregularities.

[Vimy101]

Go back and re-read post 33.

 

Read it closely. Read it a couple of times.

 

Anti-roll bars leverage each side of the suspension mostly against the chassis, less so the suspension against itself from side to side, and only when the whole chassis is involved.

 

And irregularities, as you call them, are within the range of motion of the anti-roll bar linkages, which are on two pivot pins, and move independently. that allows quick independent movements not to be transferred into the bar itself, it's chassis mounts, or the other side of the suspension.

 

The torsion bar only applies resistance to the suspension when the chassis is being rolled over by inertia, and the whole suspension system is in play, and the chassis takes up the movement in the linkage, and applies torsion spring resistance.

 

If only one wheel, and any one given instant is being affected by an "irregularity", the linkage swivels on it's bolt-pins, and the spring, strut and control arms for that wheel do their business for that event independently of the rest of the suspension. It is not transferred to the other side of the axle.

 

It's a friggin' metal bar (torsion spring) connecting one wheel to the other. This ain't rocket science.

[IwannaSportSedan]

then please, do tell what these are for, that are mounted on both ends of both swaybars. and why they have spherical joints pressed into them for friction-free rotation, but are not elastic in length.

 

http://www.vividracing.com/catalog/wm.php/images/apstirlink4a.jpg

 

Like I said... Get beyond 100-level theory. it isn't as simple as you make it out to be, and if it were, noise, vibration and harshness would be much greater than it is.

 

And even if they do impart *some* increased spring resistance under large suspension movements (like running over a big speed-bump with only one side of the car), who is to say that a little more spring rate under those conditions is such a bad thing, from preventing the suspension from bottoming out, or even bending.

 

the torque rate of twist of the bar is counted when coil spring rates are chosen for the car, and it is far from unheard of for a stock automobile to be under-sprung. Probably more common to be undersprung than optimum, or oversprung.

 

And if one wheel is affected, and the other isn't, and any bar-torsion is introduced, it is still leveraging on the off-side suspension AND the chassis mounts, which are being weighted by the car, and it's inertia to not move in an upward motion. I doubt it is going to lift the off side tire off of it's traction patch against the offside spring and the weight of the car. under body roll, the off-side wheel from the compression is being unweighted, and still isn't effected drastically enough to lift that tire more. against it's coil spring.

 

This isn't a live axle we are talking about here, where motion is transferred by an axle shaft with no torsional twisting to speak of. the torsional spring rate probably only puts a few foot-lbs of force on the opposite side, where the spring rate is hundreds of pounds per inch of spring compression, and is already pre-loaded with hundreds of pounds of car weight.

 

The difference in torsional rigidity between stock and aftermarket swaybars, in a bump situation like that is probably not that much, in terms of impacting the off-side suspension.

 

But in a constant loading situation like body roll, it obviously does make a difference, where the motion is slower, and the range of motion is probably longer. A bump is a high-speed, usually short-throw event, body roll is a relatively low speed (speed of suspension movement, not ground speed of the car) long throw event, where more and more energy is required to twist that bar, or inversely more and more resistance is imparted by that bar.

 

And as I said, most bump events are very likely handled by those little swiveling linkages.

[IwannaSportSedan]

A swiveling end link is free to swivel according to it's length when the bar is at rest. The bar is only put under stress when those linkages are pulled by suspension motion long enough to do so.

 

When the bar is being twisted by the roll effect of the chassis, the compressed side pulls on the linkage, against it's inelastic length, which pulls on the end of the bar. The bar then twists due to the input, with it's anchor at the other end, which is anchored against the offside suspension via another linkage which also gets pulled along it's inelastic length. but without being pulled against it's length, it is allowed to swivel, and isolate the sway bar from "imperfections" in the road surface that are transmitted through the tires into the suspension.

 

Besides, 5cm, the upper bound that the article mentions, is 50mm. FAR thicker than the sway bars made for the legacy, which are around or less than half that. (16mm-22mm rear, ~18-26mm front for stock and most aftermarket variants). The stock bars are near or even below the 2cm (20mm) lower bound that the article mentions as common. Even with Legacy aftermarket bars at 20 to 26mm, I doubt that is going to seriously hinder the bump-induced independent reaction of the suspension, which is what touched off this discussion.

 

I think the Legacy could use slightly larger roll bars than stock, and a few millimeters of additional diameter is not going to make the car handle like a live axle truck, or a Mustang. It might not even make it noticeably less smooth when straight and level.

 

I think SOA, if it were serious about a sport option legacy could even offer slightly larger sway bars, and slightly lower springs than they currently do, and still have it be a very saleable car, especially with an STI badge on it.

 

BTW, if you want a plush-riding cruiser, is that not what a 3.0R legacy is for? It probably has identical suspension settings to the current Spec B, and it has Bilsteins and 18"s as well, maybe it has steel control arms, I am not sure... (taking a sidebar into the realm of subaru's product placement for a moment)

 

Most of the automotive journalist reviewers, and some owners, that mention too much body roll in the Legacy (GT and Spec B have both been mentioned) and now even the STI is being criticized for too much body-roll... I would think that would fall under the stock setting being too lenient with body roll, with room for stiffening to find the ideal setting, without hurting the independence of the tires.

 

I never suggested a 50mm sway bar, BTW. I still stand by my opinion that a 20mm rear, and maybe +2mm on the front, with lower than stock, progressive rate coil springs (I like what I have read about the Ions for bilstein fitment), and bilstein dampers seem like they would work very well together, with better handling than stock, and very likely no discernable increase in harshness or rough ride. I never said people shouldn't stay stock if they want that. I said I think it would be better for performance, and not any more of a kidney punching ride. Progressive rate front springs might actually help make it a bit smoother, even, with less initial spring resistance to those imperfections in the road surface, but a spring-rate ramp up to more roll-resistance and lateral grip.

[IwannaSportSedan]

you are right, the bar is connected to the other side. I don't deny that. never have.

 

but the link moves and swivels before the bar twists, and if the bump is a small one, the link movement is probably all that is needed, and bigger bumps, sway bar might actually twist. but probably not that far, and for not that long of a time.

 

Anti-roll is about limiting long sustained chassis motion. And when the body rolls, the chassis mounts try to change orientation, twisting on the cars length axis, in comparison to the suspension location, so the chassis mounts do come into play in body roll, and is why they are as far apart as possible.

 

Anti-roll bar twist spring rates are quite a bit less than the coil spring rates, and that adds to the coil spring rate on the compression (bump or roll) side of the car.

 

It fights against the coil spring rate on the other side. (also against the unsprung weight of the suspension and wheel assembly) if the anti roll bar rate is less than the coil spring rate, it is at very significant mechanical disadvantage on the off-side, and unlikely to cause a lot problems with that side's stability for just a bump, unless the bar is so thick that it overcomes the coil spring rate.

 

Is there no one with aftermarket bars on their car that can comment with experience in this case? Evidently people aren't believing me, even though I have explained it at great length, even for me.

 

I don't think a few millimeters additional diameter on the Legacy's bars are going to upset the chassis and cause this much feared disturbance and harshness, but I have read previous driver impressions that it does add that bit of extra resistance to the stock roll behavior that Legacy drivers notice, and journalists mention during comparisons and reviews.

[Vimy101]

Most of the automotive journalist reviewers, and some owners, that mention too much body roll in the Legacy (GT and Spec B have both been mentioned) and now even the STI is being criticized for too much body-roll... I would think that would fall under the stock setting being too lenient with body roll, with room for stiffening to find the ideal setting, without hurting the independence of the tires.

 

 

The Spec. went head to head against some able peers and spanked them on the track. The suspension works very well. I driven a lot and have always tested the envelope with all my cars. I have learned and am still learning that situations and conditions that should be severly getting to the edge of my comfort zone are handled like it's just another walk in the park for the Spec.

 

Adding stiffer sways will affect the independence of the suspension by definition. Links will help (as they're supposed to) but a stiffer bar will move those guys around too and they are eventually connected to the contact patche(s).

 

It's not like we've read many posts on this site about roll induced capsizing of LGTs. Outbacks are another story.

 

All that said, mod the hell out of your LGT. I want to see what happens good and bad.

 

As an aside, better initial brake bite is the big thing that needs improvement. The brakes are pretty good (at least with good tires) but vague on the initial pedal impulse. Setting things up at the right instant is paramount to me. Infiniti is good at that.

[Spoonwacker]

It's not like we've read many posts on this site about roll induced capsizing of LGTs.

 

I would be remiss if I didn't post this pic, even if it wasn't roll-induced:

http://img209.imageshack.us/img209/1850/motivator7698843hv7.jpg

 

I also feel like tossing out there the fact that I have Cobb front & rear sways on my LGT, and can't honestly say that ride quality is worse. If a big bump under one side of the car is harsh enough that it transfers the bump to the other side of the car, it's probably big enough for the stock sway bar to have done the same. The roads I drive tend to be either awful (downtown Seattle potholes and freeways), or pretty decent highways with the occasional expansion joint that hits both wheels at the same time. I'll report more next month, when I'll add Bilstein HDs and Swift Springs into the mix...

 

I definitely agree on the brakes - feel could be vastly improved. I'm thinking of moving to SS lines, better (higher cf) pads, and stock-size DBA slotted rotors (yeah, I know blanks work fine, but that's another concession to bling ) to help that out.

[Vimy101]

^ That pic is just so wrong!

 

Obviously, the anti roll bars were less than necessary for optimal handling and anti-capsizing.

 

As for brakes, I would like better initial feel and might just install SS lines at the 60k maintenance for fun.

[psi365]

Regardless if what a sway bar does the LGT could use better ones.

[Vimy101]

Regardless if what a sway bar does the LGT could use better ones.

 

Springs are the primary anti roll device.

[IwannaSportSedan]

Then the legacy is seriously undersprung, as well as the new STI.

 

an un-tethered independent suspension with no anti-roll bars would either be completely wallowy and uncontrolled with springs soft enough to provide a smooth ride on the straight and level, or so rock solid stiff to resist roll, that the ride quality would be significantly poorer, if the low side suspension could not leverage on torsion springs anchored to the chassis, and the other side of the suspension.

 

As the car rolls to one side, the weight of the car, plus inertia forces on that weight, based on velocity would bottom out and completely overcome the compressed suspension, if it weren't leveraged. by a spring bar.

 

If you were to take a turn over about 20mph, just relying on the coil spring rates, it would probably toss the car into a roll-over that would likely kill you. And if the coils were hard, it would take more speed, but it would eventually roll the car over the uncompressed suspension, as well.

 

It is like a slot car going to fast into a curve, it's inertia spins it off the track. then you get a picture like the one posted above

[psi365]

Springs are the primary anti roll device.

 

Not so much, the entire reason for a sway bar is to make the car not "sway" around a turn. This is furthered by guys that do serious offroading/rock crawling that have sway bar links that you can disconnect to let the suspension further articulate cause they aren't as worried about taking turns at speed.

 

A springs primary purpose is to provide a more comfortable ride over bumps. Springs are added so the axles so it can articulate with the least amount of transfer of that movement into the cabin.

[Vimy101]

^ Stiffer springs, less roll.

[psi365]

[wikipedia]

A sway bar (also stabilizer bar, anti-sway bar, roll bar, or anti-roll bar, ARB) is an automobile suspension device. It connects opposite (left/right) wheels together through short lever arms linked by a torsion spring. A sway bar increases the suspension's roll stiffness -- its resistance to roll in turns, independent of its spring rate in the vertical direction.[\wikipedia]

 

Again the main purpose for a sway bar.

 

[wikipediea]

A Coil spring, also known as a helical spring, is a mechanical device, which is typically used to store energy and subsequently release it, to absorb shock, or to maintain a force between contacting surfaces. They are made of an elastic material formed into the shape of a helix which returns to its natural length when unloaded.

Coil springs are a special type of torsion spring, the material of the spring acts in torsion when the spring is compressed or extended.

The two usual types of coil spring are:

• Tension coil springs which are designed to resist stretching. They usually have a hook or eye form at each end for attachment.

• Compression coil springs are designed to resist being compressed. A typical use for compression coil springs is in car suspension systems.

Metal coil springs are made by winding a wire around a shaped former - a cylinder is used to form cylindrical coil springs.

http://upload.wikimedia.org/wikipedia/commons/thumb/8/80/OxyCutCoilSpring.JPG/180px-OxyCutCoilSpring.JPG http://en.wikipedia.org/skins-1.5/common/images/magnify-clip.png

Oxy-cut spring showing deformation due to loss of tempering in adjacent turn

Many types of coil spring are wound in an annealed (soft) condition and then tempered to achieve their strength as a spring. Over time, this tempering can be lost and the spring will sag because it can no longer withstand the loads applied. Such springs can be re-set by annealing, returning to their original length (or deliberately setting them to a different length) and then re-tempering. Damage to springs, such as using oxy-acetylene to cut the end off a car suspension spring to lower a vehicle's ride height, can destroy the tempering in localised areas of the spring.

<DIV class=printfooter>Retrieved from "<A href="http://en.wikipedia.org/wiki/Coil_spring"><U><FONT color=#810081>[\wikipedia]

 

Read, learn, understand.

[Vimy101]

^ Put steel bars in in place of springs and you'll have no roll at all except from the tires compressing.