Well, I've been working on an 80s American Muscle car for a few dozen hours now, and it's almost perfect. The only problem being, it is hilariously unstable at speed when turning or braking, making high speed corners almost impossible without losing the rear end. I suspect this is mostly because I tried cramming a 4.6L V8 into a compact car (I didn't realize quite how small the body was until it was too late), resulting in horrible weight distribution, but I quite like how it looks. So before I give up, I was wondering if anyone who's better at suspension tuning than me wanted to try their hand at fixing this thing. Note: It already has maxed out rear downforce, it didn't really help The weird steering setup is intentional, I tried to encourage understeer, which kinda worked The mismatched tire sizes are also intentional for the reasons above If you want to see what I mean, just try to take it through the slingshot at the Automation test track
Have you measured downforce in BeamNG? Some body shapes don't work at all how Automation claims, but are rather different, I have had cases where putting rear wing and adjusting it to max in Automation did not change anything in BeamNG. There are bit more info and info how to measure downforce: https://www.beamng.com/threads/is-y...ecially-at-speed-intro-to-aerodynamics.56379/
I completely forgot about that, yeah. That could be part of the problem, I'll check it it. Thanks --- Post updated --- Ok so it turns out the spoiler was working pretty well, but a mere 60 kgs of downforce wasn't enough to counter the awful weight distribution. Sticking a massive wing on it so it got 250 kgs of downforce did the trick though. But now it looks kinda ugly. Maybe I'll just give up and put a smaller engine in it...
Did you have 60kg at rear or total? For me many cars I make have completely opposite downforce balance than what Automation claims and for some wings don't change anything. For some vehicles only way to get DF to be like what AM claims seems to be editing coltris parameters, but that really depends a lot from bodyshell, for some wings seem to have effect, there is still so much to learn Last time today I had car that in AM was having only lift, terminal oversteer and all that, but in BeamNG that has huge rear downforce and leans more towards understeering, only with aggressive throttle usage one can make it oversteer. So it is kinda hit and miss with the straight exports, also 50kg change seems to have very big effect in BeamNG, at least with some exported vehicles. Of course big engine does not help, but effects of aero I find being hugely strong with these vehicles.
It was 60kg at the rear @120 mph, the weight on the front basically stayed the same. The big wing put about 200 kg on the rear, and took around 50 kg from the front.
That is kinda good size guy at boot Another thing I forgot to mention is weight and weight distribution, I have seen well over 100kg differences between AM and beam, also several percent weight distribution difference. Then when using solid axle, that tends to bug out too, need to modify links just tiny bit to get suspension to actually work instead of locked up links bending being the suspension. You can test this with node grabber, if 100kg is not making much compression of rear end, then you have locked links issue. I did made quick fix to your rear suspension, try if you like that better, I did not test it, but same edit has worked fine for me before.
I can't say it made a difference, but thanks for trying. I think it's just the weight distribution that's the problem. Compared to the Barstow and the Dodge Charger, it isn't actually that bad though, so I just might be expecting too much from an 80's pony car. I'll just try to find a big wing or something that looks decent on it. But thanks for the help anyway. I'd like to know more about that fix too, it might come in handy in the future.
Fix is really simple to do, if you compare this and original rear suspension, you see these are different: //body mounting points for lower links {"nodeWeight":12.448469}, ["rx1r",-0.391572, -0.391572, -0.117893], ["rx1l", 0.391572, -0.391572, -0.117893], //body mounting points for upper links ["rx2r",-0.391572, -0.371572, 0.097893], ["rx2l", 0.391572, -0.371572, 0.097893], For lower links last Z value I changed from -0.097893 to -0.117893 For upper links middle Y value I changed from -0.391572 to -0.371572 Most of my solid axle equipped vehicles don't have weight transfer to rear when accelerating, but that change has fixed them. Oddly some random car does work. This rear wing on this body seem to be exported just fine in terms of aero, wing even has coltris so knocking off wing has some effect, for other exports of mine wing has been just visual element, one had nodes and beams, but no coltris, so it is really bit random what you get from exporter at the moment, but those clever developer guys probably will fix those issues. I think that this wing was a mod from steam Workshop, not perfectly sure. Also I found out that creating F136 is not perfectly possible, at least with my skills, there are always these limitations, but I guess it is part of the fun to try figure out ways past the limitations.
Ok, I noticed my car liked to lift the inside rear wheel when cornering, which probably wasn't helping. Softening the rear suspension and sway bar seems to have made it a bit less likely to lose it when braking (I think the wheel would lift off when cornering, lock up because of brakes, and when weight shifted back over it would stay locked, leaving you with only 1 rear wheel effectively).
Contrary to guides etc. I tell to remove rear ARB completely, those old cars usually did not have rear ARB, maybe sportiest versions with handling packages had, but ARB is a device which purpose is to reduce grip and for rear it rarely does any good (except maybe for drifting and racing on road circuit). Also advice to have rear stiffer than front is for newer than year 2000 FWD things. Old fashion RWD is bit different, softer rear than front for longer travel, no ARB for longer travel, so that rear end stays planted, front ARB can be set so stiff that inner front lifts off at corners, that is how they used to set those RWD cars. Try 1.6Hz front and 1.4-1.5Hz rear, adjust damping to something like 0.3-0.35 for BOTH ends, front ARB 3000-4000 maybe, that would be my starting point, but one needs to tune it from there on to find nice balance.
Oh wow, that made a world of difference. It still needs tuning, but it handles a lot better. I guess you don't tune an old pony car like a modern sports car... But anyhow, it still needs to be stiffer, I want more late 80s sports car and less malaise era "sports car", but it's a great start. Thanks for the help
You can go to something like 1.8Hz front and 1.6Hz rear, problem increasing rear is that amount of travel decreases fast at some point, but of course you can stiffen dampers instead to gain some 'stiffness' without sacrificing travel, just don't overdo that, it is a lot about testing and finding balance. I like to set my dampers way different than exporter puts them out, from some reason it exports slow rebound and slow bump as same, but for comfort that should be 3:1 and 2:1 or even 1.5:1 for handling, that is rebound/bump ratio. You can test my VSTO for example how different my damping is to drive. I use formulas made for Koni shock absorbers planning from IRL, that too is of course just a starting point, but I see quite different damper values used in games than what I have seen IRL and when I put IRL values, at least for me it feels like an improvement.
I'll have to look into that, seems like another 10 hours just got added to my "quick pony car project". Oh well, not like I've got anything better to do. I'll pick it up tomorrow and see what I can do. Thanks for the help.
Goosah just informed to exporter thread that they found problem with solid rear axle setups and they will fix that at some point, my 'fix' kinda just moves pieces just enough for coltris to pass without collisions, but sometime in a future that issue will be sorted as root of the problem has been found.
