Interesting info: Rear ARB sizes for all 997 models inside!
Discussion
Hi there
I love all tech type stuff and others may find this interesting especially those tuning the handling dynamics of their cars with roll bars:-
997.1 C2S PASM rear ARB to be 19.6 x 2.6 mm
997.1 C4 standard 22.5 x 3.5mm
997.1 C4 PASM 18.5 x 2.5mm
997.1 C4 sports 19.6 x 2.6mm
997.1 C4S PASM 18.5 x 2.5mm
997.1 C4S sports 19.6 x 2.6mm
997.1 Turbo w/o rear diff lock 21.7 x 3.0mm
997.1 Turbo with rear diff lock 22.5 x 3.5mm
997.1 GT3/RS 23.6 x 3.5mm
997.1 GT2 / 997.2 GT3 25.2 x 4.4mm
997.2 C2 standard 18.5 x 2.5mm
997.2 C2 PASM 18.5 x 2.5mm
997.2 C2 PASM + sports 18.5 x 2.5mm
997.2 C2S PASM 19.6 x 2.6mm
997.2 C2S PASM + sports 18.5 x 2.5mm
997.2 C4 standard 20.7 x 2.8mm
997.2 C4 PASM 21.7 x 3.0mm
997.2 C4 PASM + sports 20.7 x 2.8mm
997.2 C4S PASM 21.7 x 3.0mm
997.2 C4S PASM + sports 20.7 x 2.8mm
Interesting info and clearly shows on 997.2 GT3 Porsche fitted the rear GT2 bar to dial out understeer the new GT3 had.
Anyone knows any other measurements be good to add them to this thread.
Even better is the rear arbs direct from Porsche are only approx £150
I love all tech type stuff and others may find this interesting especially those tuning the handling dynamics of their cars with roll bars:-
997.1 C2S PASM rear ARB to be 19.6 x 2.6 mm
997.1 C4 standard 22.5 x 3.5mm
997.1 C4 PASM 18.5 x 2.5mm
997.1 C4 sports 19.6 x 2.6mm
997.1 C4S PASM 18.5 x 2.5mm
997.1 C4S sports 19.6 x 2.6mm
997.1 Turbo w/o rear diff lock 21.7 x 3.0mm
997.1 Turbo with rear diff lock 22.5 x 3.5mm
997.1 GT3/RS 23.6 x 3.5mm
997.1 GT2 / 997.2 GT3 25.2 x 4.4mm
997.2 C2 standard 18.5 x 2.5mm
997.2 C2 PASM 18.5 x 2.5mm
997.2 C2 PASM + sports 18.5 x 2.5mm
997.2 C2S PASM 19.6 x 2.6mm
997.2 C2S PASM + sports 18.5 x 2.5mm
997.2 C4 standard 20.7 x 2.8mm
997.2 C4 PASM 21.7 x 3.0mm
997.2 C4 PASM + sports 20.7 x 2.8mm
997.2 C4S PASM 21.7 x 3.0mm
997.2 C4S PASM + sports 20.7 x 2.8mm
Interesting info and clearly shows on 997.2 GT3 Porsche fitted the rear GT2 bar to dial out understeer the new GT3 had.
Anyone knows any other measurements be good to add them to this thread.
Even better is the rear arbs direct from Porsche are only approx £150
The 997.1 GT3 ARB doesn't exist anymore.
It was too small and Porsche superseded it to the GT2 size.
This bar spec was then given a new number and applied across the entire GT3 range for both 997.1 and 997.2
There was no notice of the change however. It's up to owners to be proactive and buy a new one if they have the original small version.
It was too small and Porsche superseded it to the GT2 size.
This bar spec was then given a new number and applied across the entire GT3 range for both 997.1 and 997.2
There was no notice of the change however. It's up to owners to be proactive and buy a new one if they have the original small version.
fioran0 said:
The 997.1 GT3 ARB doesn't exist anymore.
It was too small and Porsche superseded it to the GT2 size.
This bar spec was then given a new number and applied across the entire GT3 range for both 997.1 and 997.2
There was no notice of the change however. It's up to owners to be proactive and buy a new one if they have the original small version.
Yep I remember you saying, as it was a good move to help cure understeer on the 997.1 GT3s.It was too small and Porsche superseded it to the GT2 size.
This bar spec was then given a new number and applied across the entire GT3 range for both 997.1 and 997.2
There was no notice of the change however. It's up to owners to be proactive and buy a new one if they have the original small version.
I did try a GT2 bar in my 997.1 C2S, but I gave too much oversteer, even on softest setting. No doubt simply due to the lack of grip in the rear on a C2S with it's skinnier tyres and lack of LSD.
Am contemplating giving the stock C4 bar a go as at 22.5 x 3.5 mm it's thicker than my C2S bar but nowhere near as thick/stiff as the GT2 bar so worth a go I think to see if it gives me the result I need.
I am not surprised you had over steer with a GT3 rear bar as the front will be too soft and also you will not be running enough negative camber on std C2S suspension.
The roll bar is just a final adjustment in my book, the spring rate and damper settings have to take priority then adjust with the bar. If still on std dampers/springs then the bar may be too stiff for the setup?
How is the engine upgrade coming along ?
Mike
The roll bar is just a final adjustment in my book, the spring rate and damper settings have to take priority then adjust with the bar. If still on std dampers/springs then the bar may be too stiff for the setup?
How is the engine upgrade coming along ?
Mike
I had one of the 1st 997.1 GT3 RS's in UK, ( orange 2006 car) and upgraded this pretty soon after purchase.
I wouldn't have said this is I final solution to dialling out the understeer. I ran the new bar on full stiff, and the car was pretty damned snappy on the limit. Never had a chance to move the bar off of full stiff to try next setting down, before I sold it, and am now on passive dampers on my green car, so will never know.
G.
I wouldn't have said this is I final solution to dialling out the understeer. I ran the new bar on full stiff, and the car was pretty damned snappy on the limit. Never had a chance to move the bar off of full stiff to try next setting down, before I sold it, and am now on passive dampers on my green car, so will never know.
G.
majordad said:
Reading the above I might consider swapping a7 GT2 rear bar for the one on my 7GT3, anyone wtb my 7gt3 bar cheap ? PM me.
gibbo if he is wanting a smaller one what diff set up do you have gibbo?
some details on this and what front bar you had fitted would be nice.
Edited by fioran0 on Monday 7th January 15:23
sportsandclassic said:
I am not surprised you had over steer with a GT3 rear bar as the front will be too soft and also you will not be running enough negative camber on std C2S suspension.
The roll bar is just a final adjustment in my book, the spring rate and damper settings have to take priority then adjust with the bar. If still on std dampers/springs then the bar may be too stiff for the setup?
How is the engine upgrade coming along ?
Mike
Engine upgrade, you mean remainder of X51 kit?The roll bar is just a final adjustment in my book, the spring rate and damper settings have to take priority then adjust with the bar. If still on std dampers/springs then the bar may be too stiff for the setup?
How is the engine upgrade coming along ?
Mike
If so brain kicked in and said why you spending so much money for 10-15BHP at which point I though mmmm a lot of money for a small increase. So spent the money on tyres and other stuff.
fioran0 said:
aarrgghh,
you beat my edit:
what diff and front bar have you got on the car with the 997.2 rear one?
Got 997.2 front on softest, though the front bar did not change from 997.1 I am told. I love the front, its great, but with rear 997.2 bar its too oversteer in wet. On a dry track day I did the car was almost perfect.you beat my edit:
what diff and front bar have you got on the car with the 997.2 rear one?
Like Mike says if I had GT3 springs/dampers I'd be OK, but I do not, so I need a rear bar not quite as stiff.
Car has no diff, its just regular open diff Carrera has. I've thought about a diff due to the extra traction they give, especially in the wet, but at the same time having a diff will also spin you around quicker when the back-end lets go compared to an open-diff car, not sure if true though.
the diff question was simply to establish your baseline as it related to the cars balance. without a diff you will have much less natural push than a 997 GT3 (even allowing for their weak diff).
a fast dry setup will not be a good wet setup and a good wet setup will leave a bunch on the table in terms of dry.
if you only run road tyres and want a compromised dry/wet dual setup then it should be achievable however one has to accept the limitations that will be present in each condition. be careful of just chasing your trail round and round.
it may be time to sit down and think through logically what you want to achieve going forward with the car and your expectations for it. if you dont you just end up shelling out a ton of money and get nowhere. having a well balanced and rewarding car doesnt always require changing a ton of bits either. just a methodical approach.
a fast dry setup will not be a good wet setup and a good wet setup will leave a bunch on the table in terms of dry.
if you only run road tyres and want a compromised dry/wet dual setup then it should be achievable however one has to accept the limitations that will be present in each condition. be careful of just chasing your trail round and round.
it may be time to sit down and think through logically what you want to achieve going forward with the car and your expectations for it. if you dont you just end up shelling out a ton of money and get nowhere. having a well balanced and rewarding car doesnt always require changing a ton of bits either. just a methodical approach.
Edited by fioran0 on Monday 7th January 16:08
fioran0 said:
But springs/shock settings and sway bars are controlling different things?
Spring and shock settings are primarily concerned with wheel control and fore/aft movement while sway bars are primarily concerned with roll and its associated side/side forces.
Hi Neil,Spring and shock settings are primarily concerned with wheel control and fore/aft movement while sway bars are primarily concerned with roll and its associated side/side forces.
I agree with what you say but you can't run one with out the other... you are trying to have a roll bar that was designed to work in conjunction with a certain drive line setup, not just the stiffest bar will do.
If the dampers/spring rates are not firm enough then you end up with all sorts of geometry related issues running a stiff bar. If loaded up on one side quickly it will jerk the other side up a lot faster if on std spring/damper rates....
Best option is to get stiffer springs and adjustable dampers.
mike
fioran0 said:
the diff question was simply to establish your baseline as it related to the cars balance. without a diff you will have much less natural push than a 997 GT3 (even allowing for their weak diff).
a fast dry setup will not be a good wet setup and a good wet setup will leave a bunch on the table in terms of dry.
if you only run road tyres and want a compromised dry/wet dual setup then it should be achievable however one has to accept the limitations that will be present in each condition. be careful of just chasing your trail round and round.
it may be time to sit down and think through logically what you want to achieve going forward with the car and your expectations for it. if you dont you just end up shelling out a ton of money and get nowhere. having a well balanced and rewarding car doesnt always require changing a ton of bits either. just a methodical approach.
I found this out! a fast dry setup will not be a good wet setup and a good wet setup will leave a bunch on the table in terms of dry.
if you only run road tyres and want a compromised dry/wet dual setup then it should be achievable however one has to accept the limitations that will be present in each condition. be careful of just chasing your trail round and round.
it may be time to sit down and think through logically what you want to achieve going forward with the car and your expectations for it. if you dont you just end up shelling out a ton of money and get nowhere. having a well balanced and rewarding car doesnt always require changing a ton of bits either. just a methodical approach.
Edited by fioran0 on Monday 7th January 16:08
Fitted GT2 bar end of Summer, car felt ace on hot dry days, did a track day etc. etc. Car was very neutral, no push at all.
Then it rained and I was witnessing oversteer even at corner entry, quite frightening experience infact.
With the C2S bar on I have lots of push in the wet and overall the car does drive very nice, very managable as the push can be turned into power oversteer.
I can only try and next on the list is 997.1 GT3 bar probably on middle setting as I think if I read right, the GT2 bar is 30% stiffer than the gen1 GT3 bar even when the gen1 bar is set to full stiff? If GT3 bar don't do the trick then I can try the 22.5mm x 3.5mm C4 bar. I might just end up back at square 1 with the C2S bar back on but as these bars cost sub £200 from OPC I don't mind giving a couple more a try.
Mike who knows, I might end up changing the entire suspension, shall see how it goes.
I've just booked 3rd February (Sunday) at Donnington, you coming?
Gibbo205 said:
I found this out!
Fitted GT2 bar end of Summer, car felt ace on hot dry days, did a track day etc. etc. Car was very neutral, no push at all.
Then it rained and I was witnessing oversteer even at corner entry, quite frightening experience infact.
With the C2S bar on I have lots of push in the wet and overall the car does drive very nice, very managable as the push can be turned into power oversteer.
I can only try and next on the list is 997.1 GT3 bar probably on middle setting as I think if I read right, the GT2 bar is 30% stiffer than the gen1 GT3 bar even when the gen1 bar is set to full stiff? If GT3 bar don't do the trick then I can try the 22.5mm x 3.5mm C4 bar. I might just end up back at square 1 with the C2S bar back on but as these bars cost sub £200 from OPC I don't mind giving a couple more a try.
Mike who knows, I might end up changing the entire suspension, shall see how it goes.
I've just booked 3rd February (Sunday) at Donnington, you coming?
Who is the track day organiser ?Fitted GT2 bar end of Summer, car felt ace on hot dry days, did a track day etc. etc. Car was very neutral, no push at all.
Then it rained and I was witnessing oversteer even at corner entry, quite frightening experience infact.
With the C2S bar on I have lots of push in the wet and overall the car does drive very nice, very managable as the push can be turned into power oversteer.
I can only try and next on the list is 997.1 GT3 bar probably on middle setting as I think if I read right, the GT2 bar is 30% stiffer than the gen1 GT3 bar even when the gen1 bar is set to full stiff? If GT3 bar don't do the trick then I can try the 22.5mm x 3.5mm C4 bar. I might just end up back at square 1 with the C2S bar back on but as these bars cost sub £200 from OPC I don't mind giving a couple more a try.
Mike who knows, I might end up changing the entire suspension, shall see how it goes.
I've just booked 3rd February (Sunday) at Donnington, you coming?
Gassing Station | Porsche General | Top of Page | What's New | My Stuff