Kelly,

Actually the M030 front and Euro turbo front sway bars are both 22mm not 21mm, but you are correct that the rear bars are 1mm different, 20mm on M030 and 21mm on Euro turbo.

 

I know you just bought them but the best way to help reduce the understeer is to get narrower back tires. Yes, you could tweak the sways which would certainly help, however, you'd be amazed what 40mm (285-265 = 20mm per tire) narrower tire patch on the back end does.... With all the weight we deal with in the rear end, all you're doing with bigger tires is helping to keep the rear more firmly planted.

 

There are different sway bar sizes for Turbo/C4S/C2S/C2, standard vs M030, and for US vs RoW. To simplify matters, just remember that the firmest sway bar for any US 993 is the TT at 22mm/20mm (which is the same, I think for our C4S). But the firmest RoW sways are the TTs at 22mm/21mm (while I think their C4S goes only to the 20mm rear bar ...not sure on this last point, though).

FWIW, I believe the 22/21 combo to be the absolute best bang-for-buck sways you can get. You won't need any more bar than this for the street (or for moderate track work), it is considerably cheaper than other setups, and there are Zero fitment issues.

Edward

 

FWIW I just did some hr adjustable sway bars on my TT. Each bar has two holes and i set the front on the outer and the rear on the inner/tighter setting. Car definitely feels different, a little more neutral, but still understeers a bit. Probably because the front is still much thicker than stock. I think I'll end up going to a much wider front tire when the time comes. Probably 245 from the current 225. Inj your case I would recommend leaving the front bar alone and doing a 21mm euro tt rear bar or US 20mm tt rear bar. Both will yeild an improvement. Another thing to consider is the rear bar is very easy to change. The front is much more complicated.

 

aof,

Did you know what negative cambers are there in your 993 and his WRX? Typically, aggressive negative camber can help reduce understeer as it increases front tire contact patch areas under hard cornering, and understeer is casued by front tires loosing traction.

CP

 

jdoc7-
Thanks for the correction. You are absolutely right to the 22mm front bar size. I was working from memory when I did this a year ago and should know better as I get into the Autumn years of life.

My apologies.

 

Is this a great place or what!- thanks all

CP- mine are -1F, 1.5 rear and I recall him saying his fronts were -2. Can't say what his rears were. So, yes, quite a diff upfront

PedroNole- Funny enough, i did consider the 265s for a more compliant ride. In the end I went with 285s with great results from that point of view. I'll keep that in mind.

In summary, Euro TT sways will appear the way to go-but may suffer a little harsher ride-no? change rears only as suggested by kkim??. I like the latter option a lot.

Again, thanks all

 

Kelly,
It sounds like you may have mistakenly said that adding an additional hole at the end of the rear swaybar would give you additional rear stiffness. Keep in mind that moving your drop link further to the end of the bar results in LESS swaybar stiffness since you've lengthened the bar. So drilling an additional outside hole in the rear bar won't help reduce understeer, but it's still a good mod since you have some adjustability.

 

You could also try a little more negative camber up front. Take a look at Cup or GT race cars, they even seem to run more negative up front than at the rear.

 

Eric,
Yes, you are correct. Thanks for the catch.

from a Martin S. post-

...you can mount up a 21mm 993TT Turbo (RoW) bar. There is enough room to drill another hole forward of the stock hole. Connect your stock drop links into that extra hole and you'll have a stiff rear bar, and you will have more fun at the Streets of Willow. I have a 22mm front bar, 21mm rear bar and seem to have beat the understeer blues at the Streets of Willow...last year. I am now at Big Willow...no problems there with understeer.


I've not yet drilled another hole in mine (have been keeping this mod in the back of my head until I do need more).

aof-
Beauty of adding just the TT rear bar for now is...
1. save $$$ of only purchasing a rear bar.
2. it's a simple 30 minute job for rear bar change.
3. if you need more oversteer, drill another hole forward of the one that comes on the bar.
4. if you need a different front bar later, it can be installed w/o disturbing alignment.

 

aof,

You may want to consider a more aggressive (more negative camber) alignment for your car. The handling difference is significant, but so is the inside-edge tire wear. If you can make that compromise, you'll be impressed with the difference.

 

Thanks all- rear Euro TT sway gets the nod.

 

FWIW.... aof got the title wrong - he did not drive a WRX he drove an STi I just read the other side of this post on www.imprezawrxsti.com

Just thought I'd post the correction!!!

Jeff

 

Re the antiroll bars, the ride gets stiff with RS setup. Car is light and in my case, the bars are at the stiffest setting.

With the big front bar, you also bring back the understeer even with 265 tires. But... and this is where the fun starts... you can now throttle steer exiting curves.

Now this gets into serious fun territory

 

Could you link to the specific post?