Alright so I know how to do the gear ratios (kinda), Tyres, Steering, and everything else except for SUSPENSION.

I've read Bob Smith's Setup Guide and a whole lot of others but I don't know how to do it. I don't know what order to do it in. What does what. Do you change it for every car/combo. I'm sick of getting inferno setups and tuning everything I need on them except for my suspension. I'm sure Bob Smith will help me (I hope :P), thx guys

So first off lets set a combo for an example....hmm lets see,

FXO at BL gp that should do it now how would I start to set the suspension what should I do first and how should I do it,
I've heard of there being a formula??

The most confusing things for someone who begins doing new setups is the order.
The usual order I follow is:
1. Decide on a spring frequency. Bob's setup guide discusses this nicely. This is actually the biggest part of setup-vodoo. Either you choose a frequency that fits the combo or not.
2. Mathematically calculate the damper-values. Some more vodoo here, but it's within specific boundaries now. Test this without any ARBs to see how it bahaves and finetune the dampers accordingly.
3. Check F1PerfView and see wether your setup bottoms out anywhere on the track. Adjust ride-height to be as low as possible.
3. Do the ARBs now. Ideally this will not influence the car's over/understeering behaviour, only the angle at which the chassis leans to the outside of a turn. But this step can of course be used to get rid of some nasty character trait or the car.
4. Head yourself to the tyres section.

(Very basic, lacks a lot of ifs and whens, but with your trusty setup guide at hand you'll manage.)

Vain

Since I've been with LFS since before S2 days, I have many many setups, both from Inferno, and from folks in the servers (over 1700 setups). Most of the ones I use are from others in the servers, but I also have some tweaked Inferno sets as well. For the record, all my current patch U sets are derivatives of my old patch P/Q sets that I tweaked. From there, it is easy to tailor it to your driving style. I have a little cheat cheat that I printed out and go off of that. I'm at work and don't have it in front of me, but it is in the LFSWiki I believe. If you look at the wiki, the part about setups, you see Bob's setup guide, but above that you see a simple and quick setup guide. There is where you see the cheat cheat that lists, If understeering into the corner, change this and that.

I've never built a set from complete scratch, but all my sets are personally tailored to my driving. With the guide I use, it's a simple thing to think on the track "ok, I'd like the rear to rotate just a little more in that corner" and go to the garage and adjust by a click or 2.

I don't mess with springs much. I basically set it to how bumpy or smooth the track is, then set my ride height to offset any bottoming out that occurs. I do tweak it here and there for fine tuning the corner handling, but not often.

It is of my opinion that in the beginning, and in the advanced experiences of a sim racer, that setups are not a huge deal. In the beginning it is because it is hard to learn on a REALLY crappy setup, and with advanced experience, you really should be able to drive any decent set, even if it is completely different than one you usually use. But then again, with experience, you are able to make one click on a setting the difference between just getting a tire into the grass or just keeping the tire off the grass.

Once you have any decent setup as a beginner, you advance much farther by worrying about learning the tracks and the cars than you do with messing around with setups. At this stage, even just using Bob's easy race sets, it is better to worry about the tracks, cars, and your driving than the set.

I'm not sure what else to say. I could probably update my guide a bit more atm, it's been ages since I last touched it, but I'm gonna wait until the next incompatible patch incase that throws anything else out (hopefully not, should just be fine tuning stages now).

I rarely change the suspension once I've got a happy balance for a particular car, it should work for most tracks (if not all). A few of the bumpy tracks (like Sprint 2 Reverse braking into last corner) really don't agree with stiff suspension but I run softish (compared to other sets I've seen) springs anyway so I that's a non-issue for my sets.

For now your best aid is Colcob's suspension analyser (I couldn't make good sets for shit until that came along) modified with S2 car data. I'm hoping to have a spiritual replacement for those spreadsheets semi-working and available for public testing before xmas but no promises.

Vain - I'd have to disagree a bit about checking for springs bottoming out without ARBs, taking ARBs from a "finished" set could cause it to bottom out on one side just from cornering loads, whereas it wouldn't with them in place. Of course that really only affects the low setups, such as autocross, where suspension travel isn't really useful, but I thought it worth mentioning.

Well, ARBs have little to do with bottoming resistance, unlike springs where stiffer and/or more bump travel gets you less/eliminated bottoming. ARBs don't quite work like stuffer springs. Instead , they work to reduce net roll angle by removing weight from the inside tires and shifting it to the outside wheel. Basically, the roll angle reduction is due to the fact that the inside wheels are prevented from extending a far as the springs would allow. This has the benefit of keeping ride height low whilst cornering. It also allows the suspension to work better by allowing the softer springs to compress, resulting in camber gain from the suspension that would otherwise be unused if the springs are set stiff enough for the same roll resistance.

The lessened body roll angle allows better contact angle of the outside tire to the ground, all the more crucial since cornering grip is dominated by the more heavily loaded outside tire. However, too much ARB do have some major negatives. It does result in more uneven tire loading, and too much can actually result in less overall grip, especially if the inside tires are lifted off the ground, turning the car into a mototrbike. If a one-sided bump results in destabilization of the car but not bumps hitting both sides, then you know the ARB's too stiff.

Hope this clears things up on ARBs. All this assumes that LFS roll bars work EXACLTLY like the real things.

So you're saying stiffer ARBs, which limits body roll and CoG shift, somehow increases weight transfer during cornering? Please elaborate on that, sound backwards to me.

I'm saying that it basically gets you the same effect as using extra stiff springs whilst actually allowing the suspension to recover camber as designed. And that too stiff is somewhat like over stiff springs, but only on the inside end, not allowing the inside tire to contact the ground well.

For instance, a car with little rear roll stiffness and massive front rollbars would actually lift the front wheel off the ground on exit acceleration, thus less overall grip on the front. Though from pure roll stiffness point of view it seems equivalent to using equivalently stiff springs, its is not so because the front suspension could still compress and recover camber. Anyway, with the inside tire of the ultra stiff swaybar end off the grond, the overall grip is actually less, as serious load sensitivity comes to play. A great example is RL high powered but raction challenged racing RWD that lift the front off on exit accleration. It actually results in less overall grip as the car is practically a tricycle in this state, but it might be somewhat desirable due to the car's naturally tail happy nature as it induces understeer.

Yes, if both ends have equivalent roll stiffnesses, then the net effect on steady state is less weight shift for a given lateral acceleration, but during the initial turn in phase the overly stiff inside end could actually lift off the ground like over stiff springs would. This actually happens quite a bit IRL with cars running SSBS (soft springs BIG swaybar) setups.

Hope this clears up the confusion.

Quote from Jamexing :

Hope this clears up the confusion.

Sorry to say, but both of your posts have to be the most long winded descriptions of antiroll bars I've ever seen, and tbh if I didn't know what antiroll bars looked like I'd be expecting to see something out of a 50s sci-fi b-movie attached to a car going by that description. :P

On (what I think is) your second posts point: wouldn't that be more crucial in LFS if compression damping was adjustable?

Quote from xaotik :

Sorry to say, but both of your posts have to be the most long winded descriptions of antiroll bars I've ever seen, and tbh if I didn't know what antiroll bars looked like I'd be expecting to see something out of a 50s sci-fi b-movie attached to a car going by that description. :P

On (what I think is) your second posts point: wouldn't that be more crucial in LFS if compression damping was adjustable?

If compression damping was huge on both outside ends, you'll actually have a case where the outside refuses to compress quickly enough to accomodate for the lack on inside wheel droop.

IRl, ARBs are solid or hollow cylindircal bars and even blade shaped long pieces of metal that is attached to an attachement link on each end of teh suspension. When both wheels compress together and in sync, the ARBs generate no net effect, but when 2 sides move asyncronously, it acts to limit wheel droop.

@Bob's ARB comment:
Yes, that's surely right and I did think about it while writing that post. But you can't really do the ARBs before deciding on a ride height. So actually you'd have to guess ARBs, decide on ride height, check back on ARBs, and somewhere along the way fine-tune the dampers (which I like to do without ARBs, to see wether my dampers induce a neutral/oversteery/understeery behaviour).
As you said, the effect isn't too big, at least I suspect that. I only wanted to give a "Where do I start?"-guide, lesser than a "Do this!"-bible.

Vain

Jamexing - making antiroll bars 5000 times more complicated than they actually are.