Who has the stiffest rear adjustable sway bar?
#31
09-08-2009, 09:37 PM
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Join Date: Dec 2007
Location: Orange County Socal
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OT - Mike,
Thanks. I came late and it was a minor service so didn't want to bother you.
Surely I'll come calling when the Turbo charge kit I've just added crack the Lexus V8 block. LOL.
>>>>
It takes a while to go through your replies Can, i should charge you to post... J/K
>>>>>>
KA, somehow it seems like I am getting the bad end of the deal here.
Anyway, sway bar could be a frustrating topic. For one, no one publishes official specs, so consumers are left with speculations and rumors. Second, even if we do have the specs (torsion spring rate I think, not just thickness), I am not sure we know what to do with them.
Probably, the most helpful "specs" are provided by GMG: "The rear sport sway bars offers a torsional stiffness increase of 30,45 and 60% while the front front sway bar offers an increase of 15/25 and 35% over the factory bar." http://www.gmgracing.com/porsche_suspension.shtml
Since they are made by Eibach, I felt comfortable buying them, but really I have no idea how to define the "best" sway bar. Being "stiffest" to me does NOT mean being the best sway bar -- it depends on the setup and what you are looking for.
BTW, as you already know, the sway is there to a. increase lat. stiffness and b. adjust handling. If you want to just stiffen the car, I think the better route is to use higher spring rates.
Thanks. I came late and it was a minor service so didn't want to bother you.
Surely I'll come calling when the Turbo charge kit I've just added crack the Lexus V8 block. LOL.
>>>>
It takes a while to go through your replies Can, i should charge you to post... J/K
>>>>>>
KA, somehow it seems like I am getting the bad end of the deal here.
Anyway, sway bar could be a frustrating topic. For one, no one publishes official specs, so consumers are left with speculations and rumors. Second, even if we do have the specs (torsion spring rate I think, not just thickness), I am not sure we know what to do with them.
Probably, the most helpful "specs" are provided by GMG: "The rear sport sway bars offers a torsional stiffness increase of 30,45 and 60% while the front front sway bar offers an increase of 15/25 and 35% over the factory bar." http://www.gmgracing.com/porsche_suspension.shtml
Since they are made by Eibach, I felt comfortable buying them, but really I have no idea how to define the "best" sway bar. Being "stiffest" to me does NOT mean being the best sway bar -- it depends on the setup and what you are looking for.
BTW, as you already know, the sway is there to a. increase lat. stiffness and b. adjust handling. If you want to just stiffen the car, I think the better route is to use higher spring rates.
#32
09-08-2009, 09:42 PM
Join Date: Jan 2009
Location: Austin, TX
Posts: 760
Rep Power: 74 KA,
The economy is starting to recover IMO. I think there are some smooth sailing days ahead. I am the eternal optimistic you know. But seriously, I don't feel the economy here is as bad as the media portrays it to be.
As far as real estate goes, that varies by area. I have been buying some properties for investment purposes and I am finding that in certain areas, you can't give the houses away. On the flip side, there are parts of Orange County where the real estate market is pretty hot now. I've lost a few bidding wars already.
The San Diego market is doing ok. The real estate market in that area has been hit pretty severly. Now is probably a good time to buy there.
Make the move man. We have a small group of 6 speeed members here that can do some runs with ya!
The economy is starting to recover IMO. I think there are some smooth sailing days ahead. I am the eternal optimistic you know. But seriously, I don't feel the economy here is as bad as the media portrays it to be.
As far as real estate goes, that varies by area. I have been buying some properties for investment purposes and I am finding that in certain areas, you can't give the houses away. On the flip side, there are parts of Orange County where the real estate market is pretty hot now. I've lost a few bidding wars already.
The San Diego market is doing ok. The real estate market in that area has been hit pretty severly. Now is probably a good time to buy there.
Make the move man. We have a small group of 6 speeed members here that can do some runs with ya!
I should be visiting the So CA/SD area in the next couple of months. Thanks for the great feedback!.
#33
09-08-2009, 09:42 PM
Registered User
Join Date: Dec 2007
Location: Orange County Socal
Posts: 1,621
Rep Power: 157 OT - Mike,
Thanks. I came late and it was a minor service so didn't want to bother you.
Surely I'll come calling when the Turbo charge kit I've just added crack the Lexus V8 block. LOL.
>>>>
It takes a while to go through your replies Can, i should charge you to post... J/K
>>>>>>
KA, somehow it seems like I am getting the bad end of the deal here.
Anyway, sway bar could be a frustrating topic. For one, no one publishes official specs, so consumers are left with speculations and rumors. Second, even if we do have the specs (torsion spring rate I think, not just thickness), I am not sure we know what to do with them.
Probably, the most helpful "specs" are provided by GMG: "The rear sport sway bars offers a torsional stiffness increase of 30,45 and 60% while the front front sway bar offers an increase of 15/25 and 35% over the factory bar." http://www.gmgracing.com/porsche_suspension.shtml
Since they are made by Eibach, I felt comfortable buying them, but really I have no idea how to define the "best" sway bar. Being "stiffest" to me does NOT mean being the best sway bar -- it depends on the setup and what you are looking for.
BTW, as you already know, the sway is there to a. increase lat. stiffness and b. adjust handling. If you want to just stiffen the car, I think the better route is to use higher spring rates.
Thanks. I came late and it was a minor service so didn't want to bother you.
Surely I'll come calling when the Turbo charge kit I've just added crack the Lexus V8 block. LOL.
>>>>
It takes a while to go through your replies Can, i should charge you to post... J/K
>>>>>>
KA, somehow it seems like I am getting the bad end of the deal here.
Anyway, sway bar could be a frustrating topic. For one, no one publishes official specs, so consumers are left with speculations and rumors. Second, even if we do have the specs (torsion spring rate I think, not just thickness), I am not sure we know what to do with them.
Probably, the most helpful "specs" are provided by GMG: "The rear sport sway bars offers a torsional stiffness increase of 30,45 and 60% while the front front sway bar offers an increase of 15/25 and 35% over the factory bar." http://www.gmgracing.com/porsche_suspension.shtml
Since they are made by Eibach, I felt comfortable buying them, but really I have no idea how to define the "best" sway bar. Being "stiffest" to me does NOT mean being the best sway bar -- it depends on the setup and what you are looking for.
BTW, as you already know, the sway is there to a. increase lat. stiffness and b. adjust handling. If you want to just stiffen the car, I think the better route is to use higher spring rates.
#34
09-08-2009, 09:44 PM
Registered User
Join Date: Dec 2007
Location: Orange County Socal
Posts: 1,621
Rep Power: 157
When you are in town, let me know.
#35
09-09-2009, 08:35 AM
Very good information. Could you ask the Agency Power engineer to comment how their sway bar compare to stock, percentage wise?
In other words, we know it's thicker, but giving a percentage increase would give buyers a much better idea and provide the critical reference point.
An analogy: Stating Nasdaq go down 200 points is nearly meaningless without the reference point. Stating Nasdaq go down 10% immediately shows the seriousness of the situation.
The percentage increase from stock is critical information that is missing from your web site I think.
Thanks again Dan.
In other words, we know it's thicker, but giving a percentage increase would give buyers a much better idea and provide the critical reference point.
An analogy: Stating Nasdaq go down 200 points is nearly meaningless without the reference point. Stating Nasdaq go down 10% immediately shows the seriousness of the situation.
The percentage increase from stock is critical information that is missing from your web site I think.
Thanks again Dan.
I spoke with our engineer on the sway bars and this is what I was told. So hope this helps:
When comparing anti-sway bars of same configurations, both made of solid steel alloy, different diameter bars can be directly compared. Larger diameter bars have a higher bar (spring) rate. If the bars are wider, or have longer arms (moments) they cannot be directly compared. We measure in pounds-per-inch at the end link, just like a coil spring. The adjustment holes change the rate in a direct linear relationship as well. Sway bars are just torsion springs, but they effect the chassis much differently than a chassis spring.
Note that anti-sway bars are used for tuning both the roll rate and chassis balance (oversteer-understeer), and this is not just a "more-is-better" approach. The chassis setup (springs, shocks, bars, alignment, tire-wheel selection, etc.) is more important as a whole than any one element. Bars are for tuning! German cars are usually tuned light on sway bars, as much of their tuning philosophy is based on high-speed testing. Here, US enthusiasts appreciate lower speed cornering, as our "fast motoring" is much more limited. Tight corners at lower speeds are more fun (and faster) with less body roll, as the tire contact patch is larger and more stable.
When comparing anti-sway bars of same configurations, both made of solid steel alloy, different diameter bars can be directly compared. Larger diameter bars have a higher bar (spring) rate. If the bars are wider, or have longer arms (moments) they cannot be directly compared. We measure in pounds-per-inch at the end link, just like a coil spring. The adjustment holes change the rate in a direct linear relationship as well. Sway bars are just torsion springs, but they effect the chassis much differently than a chassis spring.
Note that anti-sway bars are used for tuning both the roll rate and chassis balance (oversteer-understeer), and this is not just a "more-is-better" approach. The chassis setup (springs, shocks, bars, alignment, tire-wheel selection, etc.) is more important as a whole than any one element. Bars are for tuning! German cars are usually tuned light on sway bars, as much of their tuning philosophy is based on high-speed testing. Here, US enthusiasts appreciate lower speed cornering, as our "fast motoring" is much more limited. Tight corners at lower speeds are more fun (and faster) with less body roll, as the tire contact patch is larger and more stable.
#36
09-09-2009, 09:20 AM
Join Date: Jan 2009
Location: Austin, TX
Posts: 760
Rep Power: 74 Very good information. Could you ask the Agency Power engineer to comment how their sway bar compare to stock, percentage wise?
In other words, we know it's thicker, but giving a percentage increase would give buyers a much better idea and provide the critical reference point.
An analogy: Stating Nasdaq go down 200 points is nearly meaningless without the reference point. Stating Nasdaq go down 10% immediately shows the seriousness of the situation.
The percentage increase from stock is critical information that is missing from your web site I think.
Thanks again Dan.
In other words, we know it's thicker, but giving a percentage increase would give buyers a much better idea and provide the critical reference point.
An analogy: Stating Nasdaq go down 200 points is nearly meaningless without the reference point. Stating Nasdaq go down 10% immediately shows the seriousness of the situation.
The percentage increase from stock is critical information that is missing from your web site I think.
Thanks again Dan.
#39
09-09-2009, 10:50 AM
Join Date: Jan 2009
Location: Austin, TX
Posts: 760
Rep Power: 74 Sincerely,
Me.
#40
09-09-2009, 11:10 AM
Join Date: Jan 2009
Location: Austin, TX
Posts: 760
Rep Power: 74
New question
Has anyone tried the TPC Racing bars? I looked at their products and they have a 4 way adjustable ones for the rear, this has got to be a bit stiffer if i were to go this route.
Is there a point where you do not want to cross when it comes to torsion spring rate on these cars?
Is there a point where you do not want to cross when it comes to torsion spring rate on these cars?
#41
09-09-2009, 11:45 AM
Mods, please don't close thread! There are very good questions by KA and good information by Vivid Racing.
Plus Gotboost and I are going to discuss Turbo mod for my wife's Lexus SUV next. I know it's sort of off topic though. 
Plus Gotboost and I are going to discuss Turbo mod for my wife's Lexus SUV next.
I know it's sort of off topic though.
#42
09-09-2009, 11:47 AM
Join Date: Jan 2009
Location: Austin, TX
Posts: 760
Rep Power: 74
#43
09-09-2009, 11:58 AM
Has anyone tried the TPC Racing bars? I looked at their products and they have a 4 way adjustable ones for the rear, this has got to be a bit stiffer if i were to go this route.
Is there a point where you do not want to cross when it comes to torsion spring rate on these cars?
Is there a point where you do not want to cross when it comes to torsion spring rate on these cars?
1. Handling (oversteer/understeer)
2. Ride/stiffness/road contact
3. Anti roll effect
For 1, it's a balance between front and rear stiffness. Too stiff in the rear and you car would have too much oversteer. You want just right oversteer, not too much oversteer. Too much oversteer could be dangerous in the wrong hands. Like us amateurs.
For 2, remember in some way the sway bar could make your car behave like a solid rear axle. Too stiff and certainly you could decrease the tires' road contact. That is, when you hit a bump at high speed, car goes airborne instead of following the road surface.
3 is self explanatory.
The GMG sway is the only sway on the market that provides some degree of rating.
Like I said, I don't know how we are expected to buy sway bars when no spec is every provided by any vendor? To me, GMG's percentage method is a great start and I hope other vendors would follow.
#45
09-09-2009, 12:07 PM
In addition, as already mentioned, so many other factors influence the sway torsion stiffness (material, length of sway, length of lever arm -where the holes are, construction - hollow versus solid, etc., etc.) that just stating the thickness means so very little!
You have great resource and I am certain what we (the consumers) are requesting -- specs of Agency Power sway bar in comparison to stock, in percentage stiffness increase for example -- could be done in minutes by the engineeers. GMG does it; I think so should everyone else.
Thanks for investigating this.
Last edited by cannga; 09-09-2009 at 12:13 PM.
