callipygian 911

I believe the quote I posted speaks for itself, my brother.

nile13

I believe that Steve knows more about suspension that most people on the planet and certainly has forgotten more than I ever knew. Having said that.. if you ask Steve directly whether his statement translates into: "you can work out any tire difference with adjustable sway var" he will say: "absolutely not". I truly don't see how "prime tool becomes "Any tire width combination can be compensated for with adjustable sways.". It's one tool. It's, quite probably, the most important tool. But, like any one tool, it will not overcome everything.

Would love to hear from Steve.

IainM

Great thread
I'm looking at the oz allegerita too for low weight
One factor not in this discussion is the stress on steering components
There seems to be a lot of leaky racks now we're on 18s. My 95 came with 18 solid twists, no brace & now a leaky rack
Does anyone else suspect the extra stress of more grip & weight as prime culprit in rack wear?

callipygian 911

Allow me put a finer point on it. If a car is set up to understeer or oversteer as a result of tire width differences between front and back alone (assuming all other suspension components yield neutral handling), it can be compensated for either direction by tightening or loosening adjustable sway bars. So, a car with a much wider tire in the back will have a tendency to push, and this can very easily be dialed down to neutral or to oversteer by adjustment of sway bars alone.

Ask me how I know.

race911

Uh, OK. How does that relate to available grip? (I get we're in a street driving conversation here.) Absent the nuances of session-to-session track variables, not sure I'm looking to a roll bar adjustment as a final arbiter of setup.

nile13

Porsche did specifically advise adding brace for 18" wheel usage on a 993. The part is well under $100 and is probably worth it. My own rack, however, leaked even with the brace. They are known to leak, not the best part of a 993.

nile13

Sorry, but I don't understand how all components could be set up to be neutral and one is set to move the balance. Suspension setup is a very interesting and complex equation with multiple variables. And, oddly enough, multiple "correct" results, depending on use and driving style.

What I am saying is that 205/255 tire combination, in concert with other 993 stick components, leads to understeer. If a person is changing wheels and tires, it makes sense to try to bring the car a little close to neutral behavior with choosing 225/255 combination instead of insisting on 205/255 and fighting it elsewhere, hoping that there will be enough adjustment and that that adjustment will not result in other undesirable behavior.

callipygian 911

Seriously?

While it's hardly my point that sway bars are "the final arbiter of set-up," it is obvious that once an alignment and corner balance have been completed, there are two FINAL tools for changing the over/understeer: tire/wheel selection and sway bar adjustment. Cracking open the suspension and altering the alignment on a frequent basis is costly and time-consuming, and not practical for most of us who aren't pro racers with an open checkbook. If you are cool with redoing the alignment, yes, spring selection, for example, is just as influential to over/understeer as sways. Sways, however, are only used to modulate lateral cornering forces. You with me so far? Good. I knew you would be, Ken.

The reason sways are so useful is that you can make adjustment to front and rear independently without affecting other suspension settings. Stiffer settings will reduce body roll, while softer settings will increase body roll. Softer settings will make weight transfer more gradual, with less abrupt loading. The relationship between the front and rear sway settings have a direct effect on the handling/balance of the car, referred to as roll coupling. Yes, the difference between loading of the front and rear contact patches directly affects whether a car will oversteer or understeer. Yes, to the same degree as springs. But changing springs all the time is simply not practical.

I must assume you're playing devil's advocate with me here, Ken. You're not only much more knowledgeable about this stuff than I am, you're a flipping lawyer.

callipygian 911

You say a lot of stuff.

nile13

Wow. Just wow. What a deep, important and insightful statement.

callipygian 911

I was being polite.

nile13

Thank you for being polite. Can you tell us, please, if you've actually seen an adjustable sway bar and at least know how many "adjustments" you can make with on? Just so we understand the value here.

callipygian 911

Argumentum ad hominem is impolite. Let's not derail too much, Mike! There was some good info being bandied about.

callipygian 911

Okay, I can't resist. Scotch makes me irascible in the face of Philistines.

You say stuff. A lot of stuff. Over 6000 posts in a decade. Sometimes what you say is peppered with things that make sense, but other times ... not so much. Like here:
What the? Your logics are out of calibration. This if/then conditional statement makes about as much sense as "if salami then I poop dinosaur rocket." Congratulations. You broke the operator. If there is a god of rationality, he is openly weeping right this instant.
Never said nor implied this. Neither did the quote I'd posted. Thanks, though, for setting up the pretty straw man argument. Its fun to knock things down. Wheee!
If you mean difference in tire width, as I explicitly stated, you might be surprised. I spoke with him at length on the matter but, far be it from me to speak for someone else or put words in his mouth. You seem to have a talent for that, though...
What you say here makes sense and I agree. I'm just surprised you have the gall to pretend this was the point you were trying to make with me all along because...well, I very much doubt you poop dinosaur rockets every time a loose woman dangles salami in your face! Ha! However, I have been known to be wrong on occasion... hmmm...
I shouldn't bother acknowledging such primitive baiting; this variety of low-hanging fruit is too easy. I hope you could come up with better ways to undermine an argument, though. Please research this between your thousands of Rennlist posts.

Cheers!

orangecurry

Wow. Just wow. What a deep, important and insightful statement.