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Thread started on "1" sway bar".

Re my “1” sway bar posting”
Bill, Interesting comments too, thanks. To re-start this thread, on from increasing sway bar diameter to decreasing body roll. My aim is to ultimately improve the ‘feel’ of the Aero whilst cornering, improve the feel, and speed of driving around bends. I guess this is my ultimate goal, as I think it should feel more ‘chuckable’ and more positive whilst under reasonable cornering forces.

If I can improve the handling without spending what could be wasted money on sway bars, so be it, so I’d like to pursue firstly improving the rear anti- roll bar’s stiffness as it stands. This appears to be a common point I’ve read about a few times, as well as the comments in my previous thread. So making sure all it’s connections have poly is a start, and then removing some of the fronts bars poly bushes and replacing with original rubber until it feels as neutral as I can get it. I did once have the car corning better than expected when I fitted very worn tyres on the front from the rear, it felt like it was driving around bends, with steering much quicker, I’ve never managed to replicate that, think the tyres were NCTs. Tracking was correct too, any thoughts?

I’d also be interested in comments about dampers, as I cannot see how they can help limit body roll, there are no springs or the like in them, they just restrict the speed of travel, is that not correct? Uprated springs on the other hand I can see limiting the amount of body roll, but not very much as the offside will compress less but the near side must still be free to expand to it’s limit, albeit shorter as it’s uncompressed state is.

I also drive (the Wife’s car) a Porsche 944 in standard form, and this corners with little fuss, and neutral handling, and feels very manoeuvrable. Before you think I shouldn’t compare cars, it is basically the same weight and has 4 wheels, but it does have better weight distribution and rear wheel drive. But with balancing roll bar sizes and/or amount their flex I should be able to get somewhere near it. Out of interest, if anyone is still reading at this point, it has 24mm front and 14mm rear. I still prefer the Saab though.

Be interested in any more thoughts, and if and when I reach there, I will post the information for any other future Saab owner who wants to improve their 9000.

Cheers…
 

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This could become a long one......

Suspension is indeed an art, with quite a lot of science thrown in. If you want to "stiffen" the car, then an increase in ARB diameter is one way to go, but it may not be the best. You need to understand that the ARB and springs work together, and it is generally better getting the spring rate right and fine tuning with the ARB. Springs are surprisingly cheap !

BiilJ's comments in the other thread about changing the bushes is important, but this will generally transmit more of the road characteristics to the driver, without necessarily changing the actual limits of the car. Driver feel should improve considerably and the car will feel tighter.

Dampers. Hmmmmm, dampers do an awful lot in the workings of the handling of a car. They do not affect the limits of body roll but can significantly affect the transition into roll and if incorrectly set can result in lack of travel of the spring by what is termed "jacking down". I spent over £3k on a set of dampers last year for one of my race cars.... and the lap times show the improvement, so they do work. I have made a minor adjustment to rebound at one circuit and seen lap times change by up to one second, they are that important.

All the above applies to any car, Saab tuning specialists should have better experience of what actually works on any individual car. From my memories of the 9000 Aero I would have thought a little more rear roll stiffness would help the cornering abilities of a standard car. After that you probably need to stiffen front & rear equally.

Should you want to have a better understanding about just how little you understand about car suspension, may I suggest you get Competition Car Suspension by Alan Staniforth.

I bought it, and realised just how poor my understanding is, and the lengths you need to go to to get a car properly sorted. I have used it extensively, but I know that even this book is really only provides a basic understanding.

Oh, and we haven't even considered changing rear toe-in, front & rear camber etc, all things which can have a dramatic effect, but which are not generally available on a standard SAAB. Front toe in is of course adjustable.

I suppose in summary I am wise enough to know how little I know
 

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Having driven Jez's car today I can confirm it makes a good car great.
I'm that convinced it will make a good positive benefit on my car that I have just placed my order for one.

Adding poly rear ARB bushes certainly makes the car more neutral, but in my opinion stay clear of too much poly on the front. I had poly drop link bushes and they added much harshness for little (or no) other gain. The only poly bushes I run up front are the lower rear wishbone bushes.

Nick.
 

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thoughts on poly drop link bushes
As this removes compliance from the suspension to roll bar it could be seen to make the a/r bar work sooner in roll, limiting the roll but any slight difference in bump between the suspension.. normally taken up by the rubber...is transmitted ..ie harshness... so take out all the complience ..ultimate harshness
also I think this could be the reason for tramp ..it is a resonance fed between the wheels through the a/r bar..normally damped with the rubber
I will try it disconnected methinks...
 
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