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Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

Car is understeering a bit. Here is a pic of big body roll in a 3rd gear corner.

Springs are 140, sway bar is 23mm. Changes?

rasta
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WeiBe (1987 924S 2.5t) - 931 S3

924RACR · Posted: Tue Aug 07, 2007 8:06 am Post subject:

You can probably gain a bit more control with alignment changes - what're your current settings?

But ultimately, to significantly reduce that body roll, you need to increase your roll rate, period - either stiffer sways or stiffer springs/t-bars. Springs and t-bars will probably be cheaper, at least for new parts, but more work to install.
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genikz88 · Joined: 29 Mar 2006 Posts: 64

That's not too bad actually. Here is my '88 924S with 400lb front springs and 30mm torsion bars (stock front anti-roll bar and Welt 22mm rear). Your car isn't leaning much farther.

As far as understeering, maybe try playing with your tire pressures. Also, an alignment is crucial. Lastly, a bigger rear anti-roll bar will induce more oversteer, which in my case helps the car rotate and makes understeer much less of a problem.
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Chris
'88 924S

steeny · Posted: Tue Aug 07, 2007 10:11 am Post subject:

Rasta, for that corner, you could always try putting the driver on the correct side of the car.

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1978 924 N/A
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Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

Are you implying that my personal mass is influencing Shaggy's handling?

geni, you got 15s up front and 16s in the rear? Crazy!
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

Paul · Posted: Tue Aug 07, 2007 12:32 pm Post subject:

Until you get it corner balanced....
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genikz88 · Joined: 29 Mar 2006 Posts: 64

John Brown · Joined: 07 Nov 2002 Posts: 903 Location: Leesburg VA

Put the 968 19mm adjustable (some) in the rear. Paragon sell them. Not perfect but about all you can do without spending some semi-serious money. Assuming you have the 'standard' 14mm you could also install an 18mm. Someone should have one for the low side of $100.
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John
80 931 - #931 44Cup
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morghen · Joined: 21 Jan 2005 Posts: 9095 Location: Romania

i have the same understeering problem here...i guess that you could trick it a bit by deflating the front tyres a bit....at least thats what i'm thinking now after a few beers

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!tom · Posted: Thu Aug 09, 2007 8:17 am Post subject:

I'd rather air up the rears than deflate the fronts.

That does nothing for the body roll, which will slow the handling response and increase weight transfer.

Tire pressure is a fine tuining aid -- it doesn't replace sway bars and springs.

Street tires can be safely run far above their maximum pressure rating, but if you lower the pressure much, they start to handle poorly.
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78 924 NA
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Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

StienbargerR · Joined: 28 Oct 2005 Posts: 1362 Location: Richmond, IN

wouldn't stiffening the rear just make it understeer more?

Ryan
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1978 924 NA
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!tom · Posted: Thu Aug 09, 2007 9:55 am Post subject:

StienbargerR · Joined: 28 Oct 2005 Posts: 1362 Location: Richmond, IN

oh. I stand corrected.

Ryan
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1978 924 NA
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Cedric · Joined: 27 Aug 2004 Posts: 2807 Location: Sweden

Hm. As Scott said, check your alignment, maybe try som more track friendly settings. My car was very netutral before, but as the tires started to wear out it passed over to the oversteer side. Just a little bit, but still pretty fast.

The key is to have real rubber on your wheel. If you have planned to track drive more than one time i suggest buying a set of "r-compund" tires, not really sure what you call them. Really stiff sidewalls helps alot, and they do not overheat. Current set up is about -3 degrees of negative camber. After i changed camber i gained ALOT of front end grip. But i´m to lazy to change rear. Its about -1.2 degrees. That is a cheap way of getting fast around the tracks.
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