I was wondering if one of the dev's, or anyone else for that matter. Could please explain what increasing and decreasing the bump and rebound settings do to the cars handling. I understand everything else. But those two seem to escape my understanding. All the documentation I have read discusses fast and slow of these. And neither seems to do fit here. For me at least. I was fiddling with the GT3 merc amg and was totally frustrated with the over steer on it. So on a whim I dropped the rebound to almost nothing. which was kind of the opposite to what I understood from what I had read. And suddenly gained about 1.5 seconds a lap. So I would very much appreciate some clear info about these settings. Thanks in advance for the help. Gregoryleo
First of all, if a car is constantly oversteering, soften the rear springs or stiffen the front springs until the oversteering is gone. After that check how the car handles while you're entering a corner, while you're within a corner, and while you're leaving a corner. Oversteer corner entry: Increase front bump and/or increase rear rebound Untersteer corner entry: Decrease front bump and/or decrease rear rebound Oversteer corner center: Stiffen front ARB and/or soften rear ARB Untersteer corner center: Soften front ARB and/or stiffen rear ARB Oversteer corner exit: Decrease front bump and/or decrease rear rebound Understeer corner exit: Increase front bump and/or increase rear rebound In general, a stiffer setup makes a car more responsive, but you'll lose overall grip. But if you soften the chassis too much, the car will start bouncing, which will also result in lose of grip. So you'll always have to compromise. Personally I always create a neutral setup, which slightly tends too understeer. After that is done to my personal preference I start checking lap times with stiffer/softer springs and stiffer/softer dampers, until I get the maximum out of the car with my personal skills. And for @Eisprinzessin: Kurzfassung: Am Kurveneingang übersteuern: vordere Druckstufe härter / hintere Zugstufe härter Am Kurveneingang untersteuern: vordere Druckstufe weicher / hintere Zugstufe weicher In der Kurve übersteuern: Stabilisator hinten weicher / Stabilisator vorne härter In der Kurve untersteuern: Stabilisator hinten härter / Stabilisator vorne weicher Am Kurvenausgang übersteuern: hintere Druckstufe weicher / vordere Zugstufe weicher Am Kurvenausgang untersteuern: hintere Druckstufe härter / vordere Zugstufe härter
A good explanation of how dampers work and what they do during bump and rebound: http://www.rapid-racer.com/suspension-tuning.php#Damping: Bump and Rebound. EDIT: Direct link to chapter doesn't seem to work, just go to "Damping" from the right side menu. Or read the whole thing, it's worth the time I'd say.
You can write books about that, but I have 3 rules which work for me Rule of thumb 1: the side which needs more grip has to become softer (or the opposite side stiffer) Its all about shifing the balance. Softer front is equal to stiffer rear. Softer rear is equal to stiffer front. Rule of thumb 2: which aspect to tune. Overall handling -> springs Curve entry -> front bumper Curve center -> front ARB Curve exit -> rear bumper Go as hard as possible. Respectively as soft as asolutely required. Rule of thumb 3: one side softer or the other side stiffer? If the car is too twitchy make the side which needs more grip softer If the car is too wobbly make the other side stiffer For bumpers: Soften the 'other side of the bumper' means decreasing rebound(!) and not bump on the other side (resulting in quicker load shifting)
Can't agree enough, because that's probably the most overlooked fact regarding suspension tuning. Everything is interconnected and changing one setting always has an influence on the overall balance of the whole system. So when changing one value you always have to keep the whole system and how it will react under the now changed circumstances in mind. So the general suggestion of not changing too many things too much at once is and will always be an important hint. Change one setting by small increments, then go on track and feel how that changed things. Then go back to the garage, adapt again, test again. It's time consuming, but just how it's done irl.
One thing i have never understood is how a car can be more responsive but have less grip at the same time. I just assume that if it is responsive then it will corner better and if this is the case then it must have good or better grip to do so?
See above, it's a balance thing. In your scenario the two variables at play would be 'weight transfer' vs 'surface contact'. If you stiffen up things, weight transfer will decrease because the system (car) will behave more "planted", resulting in more even weight distribution over the four wheels (the car will lean less, which means less weight is being transferred to the outside wheels). Thinking in whole-system terms, this will make the car more responsive, because shifting weight from one side to the other (or from a neutral position to one side) will take less time, simply because there will be less shift. On the other hand, a stiffer suspension means the tyres will lose contact with the surface more often (or for a longer period of time), because it takes the suspension longer to react to small dents and bumps in the road surface. This is a very subtle effect, best understood if you imagine one tyre going over a bumpy surface (every surface is always more or less bumpy) in slow motion. A soft suspension will allow the tyre to "nestle" into bumps more quickly, hence giving it the opportunity to transmit more force towards the surface it is moving along. A stiffer suspension will have the opposite effect, the tyre will "jump" or "fly" over small bumps more often, thereby losing contact for a very brief moment during which it cannot transmit a force to counter the centrifugal/lateral force when going round a bend. In conclusion, it's the improved (i.e. reduced) weight transfer that will make the car behave more responsive and the worsened (i.e. also reduced) surface contact that will make the grip drop.
I have to add: a stiff setup may be quicker but you also need to be more precise. The stiffer the setup the smaller the window will be for keeping the car on track. A softer setup is more forgiving. So rookies will be quicker with a softer setup anyway. If you cant manage to perform constant lap times a softer setup may be worth trying. If you can't feel the difference on spring changes I won't recomment playing with bumpers since these are far more in detail and even less obvious to feel. It simply doesn't make sense to finetune for the last two tenths of a second if your lap times differ by more than that.
I have to add something too. I saw a video about the Porsche 962. And the Engineer said that when you change sth at the rear end it had more effect at the front end than when you chance sth there (and the other way round). This was about Aerodynamics, but i testet it also with the suspensionsettings - and it worked very well (Camaro with little to no understeer is great). So if you got understeer - take care of the rebound in the end or in midcorner ARS in the back stiffer and the rearwing. Here is the vid. The whole vid is worth watching, but the part i mean starts at 11:36.
Thanks everyone for the input. Lots of helpful information here. I haven't had a chance to try any of it. But these are some good clear explanations. So I'm sure it will help. Keep it coming Christian, that is probably the best artical I have read to date after 4 years of sim racing. very much appreciate it. I read the whole thing.
Agree, he explains these things in a comprehensive way. Spelling/grammar ain't perfect admittedly, but it doesn't harm the usefulness. Glad it helped.
Sorry to hijack this topic but i thought i might ask here. Ok.... Biggest beginner question of sim racing. Im riding now for an 8/9 months with default setups. (only wings and fuel i tinker and sometimes TOE in/out)) Now i get the feeling of RR and its cars and want to tinker the others... But when are my suspensions stiffer? When i put down the numbers or lower or higher? ( Nm ) Thanx in advance Sven.
The number indicates how much force in N is needed to compress the spring by one unit of length (usually millimeters). So yes, the higher the number, the stiffer the suspension will be (i.e. the more force will be needed for compressing it).
Ah thanx Christian! Just wanted to edit my post. I just found also answer here: (@12.20) Very usefull when he talks about setups. ( its i racing but very usefull nontheless i guess) Again thanx for your time and Inet-site of rapid racer! Edit @ 33.30 something about rebound....
I just wanted to say thanks again for all the help. After reading all your post and applying what I learned, I had to increase the AI and additional 5% to keep up. And I have to say that having a better more stable setup has also helped with getting hit by the AI. A lot easier to stay in control and not go spinning off. @Pfalzdriver and Racki, I very much appreciate your time and input. It was very helpful. I'm finally enjoying the GT cars. @Christian That article should be stickied in the setups thread or some where easy to find. It is the bomb dude. Gotta Go Race!!! thanks again. Gregoryleo
Dumb question, can someone tell me with bump and rebound the higher the number the softer or is it the the other way around?