DougR

It looks like you went through a bunch of fiddling to get where you wanted to, but you got there in the end (a happy ending??) Basically, tweak ride height and rake, fix the alignment, then spend indeterminate amount of time dialing in rebound settings.

DougR

Driver training and driver preference as well. Still working on the training part, and at this point, who knows about my preference? I don't have enough experience to say yet, but I'm figuring it out. And nobody can predict whether I'll like an understeery or an oversteery car better. So we put a stake in the ground and work from there...

>> Stiff rear suspension helps keep the inside front planted during track out.

Yup, so like Randy's saying, increasing the load on the outside rear tire also increases the load on the inside front one. I'm still trying to digest all of that!

BTW, thanks for the comment about needing bigger bars with the greater spring rate. I hadn't drawn that conclusion, but it's perfectly logical.

LCP

Yes, I'm fairly happy all around with the suspension, but sick of the S-03's for street tires.

DougR

Well here's where I've ended up: STaSIS Track Sport, 500#/550# F/R spring rates, "sport" valving, 25.5" front fender-height, rake as suggested by Ryan at STaSIS -- 1/8", I believe -- 1/2 turn rebound in front, 4 sweeps in back.

By the time I get a feel for this setup, I should also have possession of a 19mm Neuspeed rear bar. My concession for street comfort was to go with 550# springs in back instead of 600. Ryan recommended either 500/550 or 500/600 as a starting point for a 1.8TQ, and after talking with Shine about it I decided to go with the lower recommendation and tune with the bar, if needed. A big thanks to Randy for educating me on the issue; I'm comfortable making that decision and that I understand it a little better, even if experience takes me another direction later..

I sure would love to have gone with the Motor Sport setup, to give myself yet another degree of freedom in tuning insanity :-) But, I like that STaSIS has so many of the Track Sport setups already in the field, and the Aluminum shock bodies worry me a lot more than the cad-plated steel ones for Boston winter weather. I know, I know, they're anodized... and with regular maintenance... and the suspension could always be swapped for winter... and... Sometimes, I'm just a lazy b****** and I need to plan for that ;-)

DougR

Is it ride comfort or tramlining that gets you? For what it's worth, I'm running S-03's now, and previously ran Yoko AVS Sports. The S-03's are much better in both of those areas (much less tramlining,) but the tread seems to be wearing faster.

What tires are you looking at? A colleague recently ordered a set of Goodyear Eagle F1 GS-D3 for his 2000 S4, a tire that I'm ashamed to say that I'd never heard of, but that has amazingly good results in Tire Rack's surveys so far.

ryoung

you also have quite a bit of tuning flexibility with shock rebound. The name of the game is the same -- It's about weight transfer and the load on the tires during cornering.

Where springs and bars affect all phases of corner, shocks only affect transitions and have no affect at all during steady state cornering. In the real world, though, we don't drive around at constant throttle on circular skidpads. We're trail braking, increasing steering input, getting back on the gas, and unwinding ... all transitions that move load around from tire to tire, and shocks can control the RATE that the load transfer occurs.

Just one example, a right turn, turning in at constant throttle:

As you increase steering input, load transfers from the inside to the outside tires, and the inside shocks are extending. If the rebound of the front shocks is softer than the rears, load is temporarily transferred off the right rear, onto the right front and left rear, and off the left front. Load distribution across the rear tires increases, reducing grip; load distribution across the front tires improves, increasing grip; and the car has more of a tendency to oversteer.

Thought you might like something else to think about :-)<ul><li><a href="http://www.ozebiz.com.au/racetech/theory/shocktune1.html">Shock Tuning</a></li></ul>

LCP

The AVS Sports were my second set of tires on my S4. S-03's are my fifth set. Both were 235/40's. The tramlining is a minor annoyance since it is really only bad when braking, but the ride comfort is a constant issue unless on smooth roads.

DougR

I was afraid that shocks were somehow involved in all this ;-)

DougR

What exactly do you mean by this? Were your rear tires actually leaving the road surface? Meaning, everything would compress just fine, but the spring wouldn't extend on rebound quickly enough?

Thanks,

LCP

...instead the rear springs are so stiff with so little weight on them that the rear end of the car just goes straight up the bump and feels like it is launching off of them. It doesn't really feel like the suspension is doing it's job in those situations.