I have a Jaguar F-Pace S, set up RWD at 3850 pounds, 48% front. I’ve set both the spring rate front and rear to about 1550 pounds. 80% brake can lock the front tires during acceleration. 100% brake cannot lock the front tires during deceleration. Even the brake bias tuning is so sensitive, 47% rear causes the front to lock and 46% locks the rear first. If the tires aren’t broken, brake bias tuning definitely doesn’t have enough resolution. I’m sure both need a closer look.
Cut spring rates in half with ARBs around 25 and see if that improves handling.
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I don’t race with 1500 pound springs, my point is there’s as little movement as possible and still such a disparity of grip. Thinking now though, stiff springs cause MORE weight transfer, not less, right? Or, the weight transfer is the same regardless of the springs. Depending on suspension geometry and vehicle proportions…my point is, the tires are funny.
With suspension that stiff, sneezing on the car could upset the weight balance.
If you’re braking during acceleration, aren’t you tossing a bunch of weight onto the front tires? I would expect this to cause a more severe loss of control. If you brake while the car is already decelerating, then the weight is at least partially centered, which would mean less stress on the tires when you apply the brake.
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I forgot to mention, it’s RWD. 80% braking while accelerating in 1st gear locks the front tires; the truck continues, unconcerned. At speed, careful application can use 100% braking without locking the front tires. It doesn’t feel realistic, the disparity.
So at low speed, power applied, in a rwd car with low brake pressure and rear biased brakes, you observed that the free wheels (front) lock but the driven wheels (rear) do not.
Then at high speed and somewhat higher brake pressure with all else the same, the free wheels do not lock.
There are several variables here, but these results seem to be within the range of possible, even likely, outcomes.
Is this homologated to its division? If so, I have one that is also RWD and homologated. My one is brilliant to drive, I think I have refined it to lap very quickly and be easy to control. Mine though, weighs just 3102lbs for which I sacrificed the ability to choose my brake bias (just sports brakes, which still work well) and a little bit of power. I have front and rear spoilers, the rear aero set low, front high. I have the roll bars set to 20 and 21 and the springs are nice and soft on the front at about 600lb/in, and a little stiffer on the rear - about 660. I also dropped the rear end down to match the front - 9.6in. This way it there is plenty of travel on the front to kinda soak up some of the weight transfer and the rear being quite stiff allows you to get the power down without wallowing. Hope that gives you a kinda general push in the right direction. Obviously, that tune works for me I have tailored it to my own needs. Good luck.
They just don’t feel like rubber tires. The way they lock and stay locked while generating significantly less friction… this is what I expect to see on ice. No other game or sim penalizes me for locking wheels like Forza.
According to this, dynamic friction of a car tyre on concrete is around 80% of static friction:
http://ffden-2.phys.uaf.edu/211_fall2002.web.dir/ben_townsend/staticandkineticfriction.htm
I don’t want to run the game up right now, but does the game’s telemetry show you the tyre friction to see if it’s roughly in line with that?
If one was to test back-to back deceleration force from max braking vs 4 locked wheels, maybe. I still think it feels too volatile.
I tried the rivals event at Road Atlanta with the Lotus 2-Eleven. The way the rear grips up and front goes light on corner exit… feels broken. Key example of FM7 being difficult just to be difficult.
I made a statement in the FH4 G920 FFB thread about subjective reactions and individual expectations. I believe this is a fully objective irrational grip/load relationship. I’ve played many different sims of different budgets and popularities. None of them are so touchy to trail-braking, locking the inside front, understeering on throttle in RWDs, or failing to gain traction at all if FWD.
Here’s a few things to negate this.
To Help Trail Braking:
Stiff rebound, soft bump, low deceleration, brake bias towards the rear, little bit of front toe out & soft front suspension & roll bars will help with the tail braking. Having the correct negative camber where the tires are evenly heated is crucial for trail braking. 2° front camber is a decent starting point imo.
Help with Undeersteering on Throttle (RWD):
High acceleration. Soft front anti roll bars, stiffer rear. Softer front springs, stiffer rear.
To help Unersteer (FWD)
Locked acceleration. Extremely soft front roll bars & springs, extremely stiff rear anti roll bars & springs. High rebound, soft bump. Camber is crucial. High Caster.
Hope this helps.
You misunderstand me. I know how to extract the most from the tires. I’m saying, it’s not fun, because I can’t push them as hard as I should be able to. T10 couldn’t make the gameplay more exciting, so they made the tires fickle. Weak move. Could be related to the Porsche cover car. Forza tires seem to give point for point increases in lateral grip as tire width increases. The stock tires on GT2s are proportionally much smaller on the rear, bingo, oversteer. Solution? Amplify the load-grip relationship to make that big wing add more grip. Who knows what they were actually thinking.
I don’t think that’s the reason.
Forza just doesn’t really have any different drop off effect between the compounds. Street tires shouldn’t have a similar friction curve to race tires but they do. That’s the real problem.
To the point about lotus and lift off oversteer, if you drive ANY mid engine lotus except the one eleven it behaves that way in forza. And this is not the first forza game to do so. As long as I can remember the lotus cars have been a “unique” experience with extreme lift off oversteer and complete grip and understeer when on throttle. I’ve found myself to be the fastest in a lotus when I never fully lift off the throttle even under braking. It sounds counter intuitive but leaving even 10% throttle keeps the car in line and really doesn’t impact braking distances usually because the tail stays in line.
I’ve never driven a modern lotus in real life (I rode in a mid 80s turbo 4 cylinder esprit once) so I can not argue that the behavior is accurate but I imagine it could be.
Very light car, set up very stiff on skinny tires with a majority of the weight on or near the rear axle. Sounds like a recipe for better grip under throttle taking advantage of the weight shifting farther over the driven wheels. I have no doubt it is exaggerated in forza but I see it as being possible IRL to a more controllable degree.
FM4 wasn’t impossibly touchy like this.
I’ve found the same. Even 50/50 cars benefit from gentle throttle while tapping the brake to make line corrections.
Neither have I, but the sensation of greatly amplified load/grip relationship is present in every single car in FM7.
The 2-Eleven stock setup is softer than the default race tunes. I tend to use ~600-800 pounds of wheel rate, total across the front and rear, for 3,000 pound non-aero cars (most cars with aero in FM7 can barely achieve neutralized lift anyway) in my setups to optimize mechanical grip like a normal person. Stiff springs can be advantageous not because they offer more grip and stability (which is what soft springs do) but because they restrict body motions so fully, it’s easier to control load transfer in all regions of a corner. Stupid, stupid approach, not realistic.