997GT2 rear sway bar is 25.5mm - 997GT3 rear sway is 23.9mm (discuss)...
#1
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997GT2 rear sway bar is 25.5mm - 997GT3 rear sway is 23.9mm (discuss)...
- both rear bars have 3 holes
- both bars are hollow
- i do not yet know what hole the GT2 arrives installed on
- the GT3 we know comes fully stiff
- is it stupid math to say that 1.6/23.9 (approx 7%) implies that the GT2's bar is 7% stiffer ( or do we use different math for twisting a hollow tube?)
- think i might give a sway bar company a phone call
paul
- both bars are hollow
- i do not yet know what hole the GT2 arrives installed on
- the GT3 we know comes fully stiff
- is it stupid math to say that 1.6/23.9 (approx 7%) implies that the GT2's bar is 7% stiffer ( or do we use different math for twisting a hollow tube?)
- think i might give a sway bar company a phone call
paul
#3
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Same everything else, the stiffness of the GT2 bar is about 30% more than the GT3. I would be surprised if the lever arm length is the same as well.
#7
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Yes,
It is going on my as we speak.
If you are going to order the bar (it does fit) you also need to order 2 of the bushing as the bar is bigger (don't know those part numbers).
Part Number for the rear bar is 997.333.701.94
It is going on my as we speak.
If you are going to order the bar (it does fit) you also need to order 2 of the bushing as the bar is bigger (don't know those part numbers).
Part Number for the rear bar is 997.333.701.94
Last edited by 997gt3north; 02-04-2008 at 04:50 PM.
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#8
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My rear bar came from the factory in the middle setting. Are you guys running it in the full tight setting? What effects would changing the setting make?
Flash
Flash
#10
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Update, just found a formula to calulate stiffness for sway bars
link below
http://www.kormanfastbmw.com/tantiswa.htm
basically it is:
% increase in anti-sway bar stiffness = (new diameter / old diameter) ^ 4
therefore, gt2 bar at 25.5mm and gt3 bar at 23.9mm => (25.5/23.9)^4 = 1.295
therefore it would appear to be 29.5% stiffer of a bar
therefore, Scott's statement that the middle hole is 20% stiffer that the gt3's stiffest setting is likely correct / logical
paul
link below
http://www.kormanfastbmw.com/tantiswa.htm
basically it is:
% increase in anti-sway bar stiffness = (new diameter / old diameter) ^ 4
therefore, gt2 bar at 25.5mm and gt3 bar at 23.9mm => (25.5/23.9)^4 = 1.295
therefore it would appear to be 29.5% stiffer of a bar
therefore, Scott's statement that the middle hole is 20% stiffer that the gt3's stiffest setting is likely correct / logical
paul
#12
I think the rear bar is much better in the middle setting on the 997 GT3. My GT3 was very "twitchy" when the rear bar was on the full stiff setting. The stiff setting appears to be better for the RS, probably because the RS has a wider rear track and more inherent understeer. IMHO
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#15
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997gt3north and ScottL, thank you both for the part numbers. I'll order it this week and will probably stick with the second hole.
Jean, you aircooled guys get no respect lol
Jean, you aircooled guys get no respect lol