Sway Bars for RX?
06-26-02, 04:29 PM
#17
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See my post above.
They are a custom suspension fabrication shop who can make sways for us if they get a sample (stock bars) to copy.
http://www.sanerperffab.com/
They are a custom suspension fabrication shop who can make sways for us if they get a sample (stock bars) to copy.
http://www.sanerperffab.com/
06-27-02, 03:06 PM
#18
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hrm in interested in this... and i would let them test it on my rx3... but they are in Flordia and i'm in Cali... damn I want SWAYS hehe, lets hope they can get a tester, but ya, lets hope we get some more products out there for the Rx3
03-04-06, 12:37 PM
#20
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Tuned RX's observation provided tthe missing link.
With higher Center of gravity (both static and dynamic) and given more clearences (allowable space to fit things), I would have expected RX to have more put into the sway and strut(bar) design. {as an example the stock GS4 does not come with strut-bar while RX does]. We all know that RX is not pure-bread off-roader but still for a SUV the importance of not all wheels firmly implanted on pavement has to be thought of.
The quesiton I was grappling with was, what incremental advantage would be obtained by an upgrade. Sure a beefier sway with better pre-torque built in, will be better but you can get into point of deminishing returns.
Question for all the folks looking for the improvement is ... do you seriously push your RX that hard on the streets, with abrubt lane changes etc (other than emergency manuever)?
Salim
With higher Center of gravity (both static and dynamic) and given more clearences (allowable space to fit things), I would have expected RX to have more put into the sway and strut(bar) design. {as an example the stock GS4 does not come with strut-bar while RX does]. We all know that RX is not pure-bread off-roader but still for a SUV the importance of not all wheels firmly implanted on pavement has to be thought of.
The quesiton I was grappling with was, what incremental advantage would be obtained by an upgrade. Sure a beefier sway with better pre-torque built in, will be better but you can get into point of deminishing returns.
Question for all the folks looking for the improvement is ... do you seriously push your RX that hard on the streets, with abrubt lane changes etc (other than emergency manuever)?
Salim
03-04-06, 01:02 PM
#21
Super Moderator
Originally Posted by salimshah
Tuned RX's observation provided tthe missing link.
With higher Center of gravity (both static and dynamic) and given more clearences (allowable space to fit things), I would have expected RX to have more put into the sway and strut(bar) design. {as an example the stock GS4 does not come with strut-bar while RX does]. We all know that RX is not pure-bread off-roader but still for a SUV the importance of not all wheels firmly implanted on pavement has to be thought of.
The quesiton I was grappling with was, what incremental advantage would be obtained by an upgrade. Sure a beefier sway with better pre-torque built in, will be better but you can get into point of deminishing returns.
Question for all the folks looking for the improvement is ... do you seriously push your RX that hard on the streets, with abrubt lane changes etc (other than emergency manuever)?
Salim
With higher Center of gravity (both static and dynamic) and given more clearences (allowable space to fit things), I would have expected RX to have more put into the sway and strut(bar) design. {as an example the stock GS4 does not come with strut-bar while RX does]. We all know that RX is not pure-bread off-roader but still for a SUV the importance of not all wheels firmly implanted on pavement has to be thought of.
The quesiton I was grappling with was, what incremental advantage would be obtained by an upgrade. Sure a beefier sway with better pre-torque built in, will be better but you can get into point of deminishing returns.
Question for all the folks looking for the improvement is ... do you seriously push your RX that hard on the streets, with abrubt lane changes etc (other than emergency manuever)?
Salim
I can also imagine hitting something in the road, speed bumps, potholes, dogs, etc. and the sway bar may keep better balance. I have seen what an upgraded sway bar did on my friends RX-7 and he could make incredibly good maneuvers, better than before, both on the street and on the track.
I would love an upgraded sway bar.
03-04-06, 01:12 PM
#22
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sway bar really brings a negative effect on the ride of the car, but very little improvement on handling.
Sway bar is more or less like the last component you touch on the suspension modification.
Just to give some examples. BMW is a believer in softer sway bar but stiffer shocks and springs, while the Lotus/Colin Chapman approach is stiff sways with softer springs and shocks.
I have a set of TRD shocks and springs and TRD sway in my Supra. If I can redo it, I probably will not touch the sway but get a set of Tein coilover.
Sway bar is more or less like the last component you touch on the suspension modification.
Just to give some examples. BMW is a believer in softer sway bar but stiffer shocks and springs, while the Lotus/Colin Chapman approach is stiff sways with softer springs and shocks.
I have a set of TRD shocks and springs and TRD sway in my Supra. If I can redo it, I probably will not touch the sway but get a set of Tein coilover.
03-04-06, 05:12 PM
#23
Originally Posted by JZA80MHU38
sway bar really brings a negative effect on the ride of the car, but very little improvement on handling.
Sway bar is more or less like the last component you touch on the suspension modification.
Just to give some examples. BMW is a believer in softer sway bar but stiffer shocks and springs, while the Lotus/Colin Chapman approach is stiff sways with softer springs and shocks.
I have a set of TRD shocks and springs and TRD sway in my Supra. If I can redo it, I probably will not touch the sway but get a set of Tein coilover.
Sway bar is more or less like the last component you touch on the suspension modification.
Just to give some examples. BMW is a believer in softer sway bar but stiffer shocks and springs, while the Lotus/Colin Chapman approach is stiff sways with softer springs and shocks.
I have a set of TRD shocks and springs and TRD sway in my Supra. If I can redo it, I probably will not touch the sway but get a set of Tein coilover.
Echoing Salih's point, SUV is more prone to body roll due to higher center of gravity, it would be tremendous helpful to be able to transfer force lean on one side to the other. Larger sway bar accomplishes this goal. Unlike shock/spring upgrade, sway bar does not change the geometry of the suspension and there is no need to do wheel alignment.
Last edited by TunedRX300; 03-04-06 at 06:40 PM.
03-04-06, 06:19 PM
#24
Originally Posted by salimshah
The quesiton I was grappling with was, what incremental advantage would be obtained by an upgrade. Sure a beefier sway with better pre-torque built in, will be better but you can get into point of deminishing returns.
IMHO both front and rear sway bars are undersized for a ~4 ton, tall SUV. 2006 Honda Civic SI Coupe has 22mm front, 17mm rear. My 2000 Acura TL is a heavier car, Honda appropriately gave it stiffer sways: 27mm front (hollow), 18mm rear (solid).
Here is a section I am borrowing from NSXPRIME on the effect of sway bar on over/under steer.
What are Oversteer and Understeer?
There is a technical definition and the real world one. The technical definition of understeer is when the front tires have a greater slip angle than the rears. Oversteer is when the rear tires have a greater slip angle than the fronts.
In real world terms, understeer is when the car won't turn any sharper, even if you turn the steering wheel more. At some point, the front end may start to grip less even when the steering is turned sharply and the result is the car continues in more of a straight line than a sharp turn. That is understeer.
Oversteer is when the car's rear tires lose grip in a turn while the front tires are still gripping. If the rear end starts to slide out from under you in a turn, that is oversteer.
A funny way to put it is if you smash into the wall with the front of your car, it was understeer. If you back into the wall, it was oversteer. Ok, so its not funny, maybe amusing.
Stock production cars are made to have understeer. The US legal system tends to blame the car manufacturer if the car does a 180 before smashing into a wall while if the car can't turn sharp and crunches head long into the wall, then it is the driver's fault.
Most front engine cars have understeer and kinda have to live with it. Most mid-engine and rear engine cars come from the showroom floor with understeer but can be made to handle more neutrally or even have oversteer with minor adjustments.
The following steps can be taken to decrease oversteer (increase understeer):
increase front tire pressure
decrease rear tire pressure
smaller front tire section
larger rear tire section
more positive front wheel camber
more negative rear wheel camber
more front wheel toe in
more rear wheel toe out
more negative front wheel caster
stiffer front springs
softer rear springs
stiffer (heavier) front sway bar
softer (lighter) rear sway bar
more forward weight distribution
There is a technical definition and the real world one. The technical definition of understeer is when the front tires have a greater slip angle than the rears. Oversteer is when the rear tires have a greater slip angle than the fronts.
In real world terms, understeer is when the car won't turn any sharper, even if you turn the steering wheel more. At some point, the front end may start to grip less even when the steering is turned sharply and the result is the car continues in more of a straight line than a sharp turn. That is understeer.
Oversteer is when the car's rear tires lose grip in a turn while the front tires are still gripping. If the rear end starts to slide out from under you in a turn, that is oversteer.
A funny way to put it is if you smash into the wall with the front of your car, it was understeer. If you back into the wall, it was oversteer. Ok, so its not funny, maybe amusing.
Stock production cars are made to have understeer. The US legal system tends to blame the car manufacturer if the car does a 180 before smashing into a wall while if the car can't turn sharp and crunches head long into the wall, then it is the driver's fault.
Most front engine cars have understeer and kinda have to live with it. Most mid-engine and rear engine cars come from the showroom floor with understeer but can be made to handle more neutrally or even have oversteer with minor adjustments.
The following steps can be taken to decrease oversteer (increase understeer):
increase front tire pressure
decrease rear tire pressure
smaller front tire section
larger rear tire section
more positive front wheel camber
more negative rear wheel camber
more front wheel toe in
more rear wheel toe out
more negative front wheel caster
stiffer front springs
softer rear springs
stiffer (heavier) front sway bar
softer (lighter) rear sway bar
more forward weight distribution
Last edited by TunedRX300; 03-04-06 at 06:23 PM.
03-04-06, 08:53 PM
#25
Lexus Test Driver
Properly designed sway bars will increase not only handling but driving stability in ALL situations, even normal day to day driving. They will also for the most part NOT have any detrimental effect on ride quality or driveability. This would hold especially true in the boat-like RX chassis.
I would not only disagree with the above statement that springs and shocks are more important and have less effect on driving comfort, but I would have to say it is false. This is misinformation and will confuse people who read here. The opposite would be a true statement however.
I would not only disagree with the above statement that springs and shocks are more important and have less effect on driving comfort, but I would have to say it is false. This is misinformation and will confuse people who read here. The opposite would be a true statement however.
03-04-06, 09:22 PM
#26
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Let me rephrase my paragraph -- by increasing the diameter of the sway bar will negatively affect the ride quality, and it has little to do with improving performance of the vehicle comparing to spring and shock modification. I am not saying it has no performance gain by switching to larger sways, but the improvement is not as dramatic as from shocks and springs.
There's a technical article about these products in Road and Track couple months ago.
Also, if it has no detrimental effect on ride quality, why did BMW bother to design their Active Roll Stabilization system to "decouple" its rollbars when the car is going straight, and only "stiffens" them when the car is cornering?
I stand with my opinion, from my own experience and readings.
There's a technical article about these products in Road and Track couple months ago.
Also, if it has no detrimental effect on ride quality, why did BMW bother to design their Active Roll Stabilization system to "decouple" its rollbars when the car is going straight, and only "stiffens" them when the car is cornering?
I stand with my opinion, from my own experience and readings.
03-04-06, 10:14 PM
#27
Originally Posted by JZA80MHU38
Let me rephrase my paragraph -- by increasing the diameter of the sway bar will negatively affect the ride quality, and it has little to do with improving performance of the vehicle comparing to spring and shock modification. I am not saying it has no performance gain by switching to larger sways, but the improvement is not as dramatic as from shocks and springs.
I stand with my opinion, from my own experience and readings.
I stand with my opinion, from my own experience and readings.
Accord V6 (family sedan) has 17mm rear sway, Acura TL Premium (Luxury) has 18mm , TL Type S (sport) has 19mm rear sway, on basically the same chasis. Comptech's 22mm rear sway will fit all three but AV6 owners are benefited by improved handling the most.
I don't dispute your own experience, but to convince others, please back it up by scientific reasoning or independent verification by multiple owners. My positive experience on bigger sway bar is echoed by many TL owners in this thread.
http://tl.acurazine.com/forums/showthread.php?t=120507
Last edited by TunedRX300; 03-04-06 at 10:36 PM.
03-04-06, 11:26 PM
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So just because your experience is similar with your other TL owners friends, that makes it "scientific"? So I can call my experience an "independent academic research study" also.
Fact is, in the perfect world if all the roads are mirror smooth, then we can get as stiff a sway as we can to keep the body lean in check. Reality is that we don't have that kind of roads everywhere, else all car manufacturers will just equipped their performance cars with huge solid roll bars front and rear.
So it depends on how much ride comfort you are willing to sacrifice for that extra cornering performance, on a daily driving basis in real world road condition.
Fact is, in the perfect world if all the roads are mirror smooth, then we can get as stiff a sway as we can to keep the body lean in check. Reality is that we don't have that kind of roads everywhere, else all car manufacturers will just equipped their performance cars with huge solid roll bars front and rear.
So it depends on how much ride comfort you are willing to sacrifice for that extra cornering performance, on a daily driving basis in real world road condition.
03-05-06, 12:37 AM
#29
Lexus Test Driver
TunedRX is pretty much correct with those real world statements.
Once again, a properly designed bar will increase cornering dramatically, MORE than springs and/or shocks, but will not affect ride quality to any significant degree.
On the BMW, they have a very stiff bar, which NEEDS to be decoupled when going straight. This bar would be completely objectionable when driving on normal bumps, etc. Look what they had to do because they put too stiff of a bar, geez. What does this have to do with upgrading a bar on an RX anyways???
An RX is a boat. Very bad and almost unsafe. Good bars would do a world of good, more than any shock or spring would do, and would not affect ride quality. Go ahead and put some lowering springs on one and see if that really makes it worldly better. Let me save you some time...it won't.
I believe we are talking about RX's here anyways, which should be the point of everything here. Last I checked this was the RX section of a Lexus forum.
Once again, a properly designed bar will increase cornering dramatically, MORE than springs and/or shocks, but will not affect ride quality to any significant degree.
On the BMW, they have a very stiff bar, which NEEDS to be decoupled when going straight. This bar would be completely objectionable when driving on normal bumps, etc. Look what they had to do because they put too stiff of a bar, geez. What does this have to do with upgrading a bar on an RX anyways???
An RX is a boat. Very bad and almost unsafe. Good bars would do a world of good, more than any shock or spring would do, and would not affect ride quality. Go ahead and put some lowering springs on one and see if that really makes it worldly better. Let me save you some time...it won't.
I believe we are talking about RX's here anyways, which should be the point of everything here. Last I checked this was the RX section of a Lexus forum.
03-05-06, 05:24 AM
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I am just providing my opinion on sway bars because this topic is about sway bars.
"On the BMW, they have a very stiff bar, which NEEDS to be decoupled when going straight. This bar would be completely objectionable when driving on normal bumps, etc. Look what they had to do because they put too stiff of a bar, geez. What does this have to do with upgrading a bar on an RX anyways??? "
Reread my posts. I am not saying the sways are not going to improve the cornering, but at the same time you will sacrifice ride quality when you increase the stiffness of the sway bar, just like how you interpret BMW's ARS system.
Don't get too sensitive here. Yes, this is an RX forum, but it's a discussion about sway, and I am providing examples. If you don't like the example about BMW, too bad. But we just have to get real about which company has better experience making cars with great suspension in general.
"On the BMW, they have a very stiff bar, which NEEDS to be decoupled when going straight. This bar would be completely objectionable when driving on normal bumps, etc. Look what they had to do because they put too stiff of a bar, geez. What does this have to do with upgrading a bar on an RX anyways??? "
Reread my posts. I am not saying the sways are not going to improve the cornering, but at the same time you will sacrifice ride quality when you increase the stiffness of the sway bar, just like how you interpret BMW's ARS system.
Don't get too sensitive here. Yes, this is an RX forum, but it's a discussion about sway, and I am providing examples. If you don't like the example about BMW, too bad. But we just have to get real about which company has better experience making cars with great suspension in general.