Post your build and tune - so we can compare 
For off-road I’d using rally suspension anyways which allows for greater suspension travel and is generally better suited here than race suspension.
Certainly, but I also care how cars on race tires/suspension perform in free roam rush, so I test a little off road as well.
Here’s a TVR speed:
V12 racing, races tires/susp
891hp/641 torque
1722lbs
50%
Tires 28/28, final drive 3.9
-2.2/-1.1
0/-0.1 rear toe
20/20 arbs
375.2/374.8 or so
14.3
15.6
16.3
16.5
30%/0%
80%/60%
65% rear
Auto trans and abs, I run 46.3 on bamburg circuit Probably 46 flat with a perfect lap. I’m not especially consistent.
That is SO much damping… I’d cut those by 2/3… then add a little back as necessary.
Good call, thanks. Wound up cutting by roughly half and running the same times on dry tarmac but much much better over bumps. And dropped a couple tenths off my snow time (rally tires, race susp), which is faster than my dry time. There are a few more tenths to be had from fine tuning - I reduced the oversteer for the snow version, for instance.
I also tried this approach on an S1 trailcat and an A raptor without success, although I need to retest with lower rebound. The trailcat seems especially happy with rebound*. 67 bump though. There’s clearly a bigger difference between both various suspension models and terrain and bump types than I had expected.
And I’m intrigued to try out balancing tire pressures, although even my Ford gts are either 49 or 51% front. Appreciate you sharing your experience.
Awesome. Good luck.
In FH2, rally suspension and race suspension had the same tuning ranges with different presets. I haven’t noticed a difference between race and rally. I actually use rally suspension on a number of cars, including the Hennessy Venom and 2016 GT3 RS, because it has more travel and can use lower spring rates that are easier to drive and grip better even over rough roads, let alone off-road. The Hot Wheels Mustang is lost on me. 1 inch more travel might have been enough. Ditto the McLaren F1 GT.
You can tell when the tire pressure is too low at one end when it gets wobbly and imprecise (the GT3 was suffering at 28 psi, rear; it was 35 for a while, now 33, still testing). Depending on the surface and tire type, I adjust it based on the sharpness at each end of the car, and have been aiming for front and rear to feel equal on the soft/sharp spectrum. I forgot it was important until I plugged in my 360 last week and played FM4 a bit. My setups there applied that thinking, and it was revelation then, too.
Do you have a specific example or shared turne at hand with lower rebound than bump? I’d like to compare it with my approach.
Not yet. Been having trouble with my thumb/forearm lately, too. I’ll try to make an open tune thread by next week.
Ok cool!
I’m way past being able to reply or even read all the posts on this thread. What l’m about to say refers to offroad tunes. The principles should apply to road going cars, though. The numbers just need adjusting. I’ve used different methods for spring rate and damp. I’ve usually kept my rebound around the same as my spring rate, which l kept around 500 lbs for my center. It worked. What l’m doing now is, l set my spring rate at 15 pct my weight for rally cars, and set my rebound at 5 for my center, so you end up with the same numbers as your weight distribution, so 5.4, 4.6 for a 54 front weight, and 6.0, 4.0 for 60 front weight. I set bump at 66 pct. It’s what feels right to me. It’s also my gear progression, so you don’t get any jerky stuff shifting in corners. I like the suspension telemetry look of a 5 for my rebound and 66 pct bump. It’s all car and race type, and driver style, though. So, l go 15 pct of my weight on spring rate (15 pct to center) on rally cars, and 10 pct on trucks, 12.5 pct on suv. Whatever pct l use, l also use this as center on my ar bars, so on a rally car, 15 will be center, and will add up to 30. On a 60 front, you go 30 x .60 to get your rear(18), divide by 1.5 (or multiply by .666) to get your front(12) If you add them they’ll always add up to 30 at 15 pct total weight. 20 at 10 pct total weight…etc. Basically your ar settings are weight percentages. Whatever percentage of your overall weight you’re working with should be represented by your ar bars. The pct thing is easier for me because it gives me a consistent feel relative to weight on any car, easier ar bar math, easier ride height math. Ride height? If you’re at 15 pct spring rate, take your top ride height number multiply by .85 (taking 15 pct off maximum ride height) and you’re perfect…every time. As low as possible without bottoming out…your frame or suspension. Try it. I admittedly have a lot to learn about road going cars, but can’t nobody mess with me on dirt tunes.
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How can you guys account for differing f/r tire widths by using these formulas?
I don’t ever run different tire widths. I don’t think it would affect it that much. Mainly just increase turn in response, l guess? It would create some oversteer, but l don’t think it would be that bad…my advice? Run the same tire width. If you have to, fix it in your alignment, not springs or Roll bars. It’s not a body roll issue at this point. It’s an alignment issue. You don’t want to affect your body roll to compensate for tire width…imo of course.