Can all of you guys with adjustable RS bars tell me: how often do you adjust your swaybars? Do you set them harder for track days and them soften them afterwards? Do you play around with the different holes EVERYTIME you go to the SAME track? When you find the balance you're looking for, don't you just leave them along no matter where/what track you go to?

My point is that the ROW M030 bars seem to be a better choice since most people use the stiffest points of the setting on the adjustable ones anyway...yes the sizes of the RS vs. M030 are different (23mm vs.22mm Front, same 20mm? Rear) but seems to me the RS bars are not much better??

Thoughts, helps?

 

KC993:

I have only used my 993 on the track four or five times in the last year and you are exactly right about leaving my bars set where they are. It was nice, however, to be able to set them for my driving preference. I think that if I used my car for more track events that I would change bar settings at different tracks, if required. I definitely change sway bar settings on my race car.

I think the M030 bars are fine and a nice upgrade to the standard bars. You just have to play with tire pressures to adjust the balance of your car for track use. Perhaps, one compromise would be to get the M030 front and the RS adjustable rear bar. That way you can make some adjustments that are outside of the range of what you can do with tire pressure alone.

Hank

 

Hank,

As for to get different REAR bar, I was thinking the other way around of getting the FRONT bar adjustable one...Of course counting both RS and M030 rear bars are the same size .

 

I have the RS bars, like them very much, but couple of points:

(1) RS are much more expensive (twice price ?)

(2) But adjustability is nice to set up car to your liking, esp. if a 4WD, which tends to understeer

(3) RS bars are a pain to adjust unless you can easily get car on a lift or trailer - access with the car on the ground is difficult and time consuming, made more so if car is lowered - definitely would not be on my list of things to do on a whim or for each event !

 

RS rear sway bars are 20mm. I use the stiffest setting.
Lower front tire pressure and higher rear tire pressure increases understeer, higher front tire pressure and lower rear tire pressure increase oversteer.
Too much stiffness up front causes understeer, too much stiffnes in the back causes oversteer.

 

Kevin,
Be aware that the different types of bars have different drop link requirements. If you go with the RS bars you will have to remove the rear bilsteins in order to adjust the drop link height.
I know this because I have the RS bars and tried to install the 21mm euro bar. The 21mm bar would not fit with the three types of drop links I have. The drop link bracket on the shock needed to be raised and I did not want to remove the shock to have to do that.

<img src="graemlins/offtopic.gif" border="0" alt="[offtopic]" />
I was going to return the 21mm bar to TPS but if you want I can trade you for the strut brace. Give me a call if you are interested.

Mark S.

 

Mark,

You've got mail... <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />

 

[quote]Originally posted by 993RS:
[QB]
Lower front tire pressure and higher rear tire pressure increases understeer, higher front tire pressure and lower rear tire pressure increase oversteer.QB]<hr></blockquote>

RS - That is not correct. For any given car and tire, there is a hot pressure that provides maximum grip. Changing from that pressure, in either direction, reduces grip. So, if you are at that correct pressure, raising or lowering rear pressure will induce more oversteer.

In practice, I think it is better to raise pressure to reduce grip, since that also stiffens the effective spring rate. So raising rear pressure, reduces rear grip (more oversteer) and increases spring rate (more oversteer). Since both are working together, you get understandabe, predictable results. If you do the opposite, lower the pressure which reduces grip (more oversteer) which also softens the spring rate (more understeer) you have no idea which of those two factors will dominate the change or whether they will cancel each other out.

 

Mark D,
Maybe, but that is not what Bruce Anderson says in his book, "Porsche 911 Performance Handbook",second edition, page 216.

 

Kevin,

I have my RS bars set full stiff rear, middle setting in front.

I do not change it between street and track - only soften the shocks on the street.

They are not THAT bad to adjust - it takes about half an hour each end of the car. I like the flexibility to adjust the stiffness to my driving style/capabilities as I progress.

Ben

 

[quote]Originally posted by 993RS:
<strong>Mark D,
Maybe, but that is not what Bruce Anderson says in his book, "Porsche 911 Performance Handbook",second edition, page 216.</strong><hr></blockquote>

With all due respect to Bruce Anderson, that is not correct, nor is that exactly what he wrote (he was generalizing if you read the entire section). Bruce knows a great deal about the mechanical aspects of Porsches, but I do not see anything in his CV that implies special knowledge of vehicle dynamics.

My statement (which is somewhat simpliifed for this board) is based on a degree in Mechanical Engineering, ~70 pages of text on Tires in "Race Car Vehicle Dynamics" and many, many hours and laps of trying this stuff.

 

Thanks guys <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" /> ...

When changing set up on a car, it's ALWAYS best do one end at a time(either front OR rear). I agree with Mark D. about the tire pressure however, it's easier to lower pressure than to add pressure, specially when you already have a high tire pressures when tires are hot...

On the other hand, if I use the stiffest(thickest) bar at the rear and with adjustable bar at the front to do the adjustment I think it's more ideal this way...

 

Hey Kevin,

It's much easier to adjust the rear then it is the front. It's really easy to jack the car up by the engine and have both wheels off the ground. I have yet to attempt to raise the front end of my car. It’s too low and I’m nervous. I do need to lube my front bushings, but I've been putting it off for a couple of months.

I've had my fronts in the same position for the past 18 months. I just play around with the rears.

George

 

Speaking of RS bars vs. M030, does anyone know if there is any appreciable difference between the two other than 1mm increase in the front bar and the obvious addition of adjustment holes?

I'll concede that the 1mm addition in the front bar is noteworthy, but have you noticed the differen$e in the price one pays for that 1mm? After all, we're talking about a "bar," not some gee-wiz techno-forged mysterymetal ConRod or bearing. Couldn't one achieve the same flexibility in the rear M030 bar, for example, if one had holes properely drilled in it by a competant machinist? It seems to me far more cost effective than the double+ difference in price. Or is it that the RS bar REALLY has some of that Teutonic Druid magic that the M030 lacks?

Personally, I think the "RS" label (in this one case, anyway) is just that: a label that excuses Porsche to charge an exhorbitant amount to a population willing to shell it out. Forgive my tone but whether it's Porsche stuff or a pair of shoes, I resent being raked over the coals for what oftentimes amounts to labels and image. Just my thoughts...perhaps someone can speak to the true mechanical advantage of having these RS wonderbars over the "ordinary" M030. I'll stop now. ...Rant over <img src="graemlins/xyxwave.gif" border="0" alt="[bigbye]" />

Edward

 

Reply to George on adjusting with both wheels off the ground - isn't your swaybar under some considerable stress then ? And so pretty difficult to move position ?

It should be unloaded only when the car is static, wheels on the ground. At which point in my experiencem, its still a pain to manipulate and reattach on a different setting.

Or have I got this completely wrong ?