I see a lot of the super fast guys running all kinds of weird (i.e. old muscle cars) cars that get around really fast. Obviously a lot of it comes down to technique, but when I have tried these builds I’ve found that my biggest impediment is rear traction. I get on the gas and the tires just spin. What are some strategies people use to help get traction to the back of these cars? And is there anything I can do technique wise to help?
You can get more stable tunes for those cars, but those people are simply employing precise throttle control to get the car under control. Jamming the throttle doesn’t work well in muscle cars, and doing so will give you a lot of wheel spin. Be lighter on the throttle mid corner and slowly ease into it, finally giving full throttle when the car is just about straight. As you improve your throttle control, you’ll be able to find the earliest possible moment to hit the throttle. Hope this helps some.
are u talking about rear traction or rear wheel spin? rear traction could be a million different things thats causing your car to be imbalanced. wheel spin can usually be cured by increasing the diff setting. u would have to give a better description of how the rear wheel “feels” when your cornering and at what part of the corner you are at when u lose traction
I am talking strictly on the power out of a turn. I generally tune for a neutral to understeer and a lot of trail braking. It’s the corner exit that’s tough. I soften the springs and turn up the toe in. I don’t really mess with the differential though, I will try it.
I like using high horsepower “heavy” cars more than most other types. I usually get the most rear traction by adjusting shock damping. Driving technique does count for a lot, though. Use trail braking to rotate the car for a late apex then power out. The V8 beasts make so much torque that losing a couple of MPH through the middle of the corner can easily be made up by accelerating earlier during corner exit.
Increasing your differential makes wheel spin worse, not better…
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Tell me more…
You can look into the nitty gritty in the tuning setting descriptions on the game, but a general rule of thumb is that the more acceleration differential you have, the more slip you’ll get on theottle out of corners. Setting it to 0% would cause the least amount of spin but often causes understeer. Deceleration is the opposite… 0% will cause the fastest entry but will often cause oversteer. Play with the values and see what suits you.
For as far as I understood it, setting the diff to 0% on acceleration basically makes it an open diff. The car won’t oversteer, but the inside rear tire will spin, hurting drive off the corner.
For deceleration that’s true, but open acceleration in the game is 100%.
Wait… what?
I’m sorry, but that’s incorrect. I just tested it with a Corvette C6 ZR1. At 0% during a slow turn at WOT the car would start to oversteer then the inside rear tire would “unload” (spin) and the car would hold its line. It was quite evident through telemetry that performance was being sacrificed since the outside rear tire was no where near its grip limits. As I’ve said many times decreasing the accel setting to extreme values give stability at the expense of traction out of the corner.
With the accel setting at 100% WOT in a turn at nearly any speed caused an almost instant spin. The telemetry showed that the torque demand for both rear tires was equal at all times. Once again at 0% under the accel setting the diff is “open.” At 100% it’s “locked.”
What it is or is not at what setting isn’t all too important though, besides understanding the concept that if your inside rear tire is spinning you are losing torque that could have accelerated you out of the turn. Personally I think extremely low accel differential settings is a bad crutch. I’ve never had an oversteer at corner exit problem that couldn’t be solved with shocks, springs, anti-roll bars, tire pressure, or alignment. it should be remember that the differential has the most effect in slow speed corners. If you’re getting power oversteer at the kink at Road America that shouldn’t be fixed by the differential unless you have a freakishly powerful car.
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Yes, the differentials work in opposite ways. Want less oversteer on entry? Raise the decel. Want less oversteer on exit? Drop the accel. That’s all you really need to know to get started.
I think you confused youself, cause what you are saying here is correct, thought badly worded. The diff locks more the closer to 100% it gets regardless of accel or decel. However the effect for each is different. A locking diff on acceleration sends torque to the outside wheel (the one with grip) which rotates the car and causes “oversteer.” A locked diff on deceleration doesn’t let the rear tires rotate freely (relative to each other), which means that they resist turning, causing understeer.
I feel like it is the opposite… when I turn up the accel it seems to lock the wheels together and force the car to push straight + understeer. Locking the back diff turns letting off the gas into pulling the handbrake… I usually put the rear decel setting no higher than ~15-20, but I feel like it could be very effective if I could set up my suspension to control that.
Yes, the accel setting on the can diff work like that, which is why performance cars have limited slip diffs since some slip (from the diff) is actually good. To be completely accurate, an open diff allows the inside and outside wheel to turn at different speeds and the torque going to both wheels is always equal. With a locked diff the wheels are not allowed to turn at different speeds, but the torque between the two wheel is not equal. So with a high horsepower car going through a turn with an open diff, excess torque will “escape” through the wheel with the least amount of traction. Or in other words, the amount of torque the car can actually put to the ground is limited by the tire with the least amount of traction since the torque between both wheels must always be equal. For a high horsepower car with a locked diff the car WILL understeer when applying power at less than the torque limits of the tires, just like on decel, because the tires are turning at the same speed and resist the turn. However, since the car has so much torque it can overpower the grip of the outside “loaded” wheel, causing the car to oversteer when the grip limits are exceeded instead of simply spinning the inside “unloaded” wheel.
As I’ve said many times, I think the diff is overly used to solve high horsepower traction problems, when its greatest effect is on slow speed corners, where the difference in wheel speed between the outside and inside tire is greatest.
I hope that helps.
Guys, The Bulin Wall5 is one of the fastest few drivers on this game, I would take his word.
When you increase accel towards 100%, the rear will try to slip more. So if your car slips a lot, peg it back to say 20%, meaning it will ‘lock’ earlier and not try to pivot about itself as much. Equally if you have all the grip in the world, loosen it up, whack it as far up as you can go 
Decel is just the inverse of accel here. If your car steps out or oversteers on corner entry, turn the decel up. However most of my tunes run VERY low decel, or none at all.
But if this is all wrong, all I’ll say is go beat Bulin on one of his crazy crazy laps 
PS: Me and him are good friends and he’s given me about 400 trillion tunes, and vice versa (but he’s ever so slightly more talented)
That doesn’t mean that he can’t still be wrong.
And this is why I said what Bulin Wall said was “correct” but badly worded. “The rear will try to slip more,” the rear of what? At 100% the rear diff is locked. It is not “slipping.” I rear tires will have a high slip angle, relative to the front, which will cause oversteer. However, at 0% (open diff) the inside rear tire will spin (“slip”) during a tight turn with high power. So yes, all you really need to know is oversteer (on acceleration) = diff lower, understeer = diff higher. Which is what he said, but the terms and understanding of why were wrong.
Restated in a more “correct” way. “So if your car oversteers on power in slow speed corners, peg the accel diff setting back to say 20%, meaning it will allow more slip, which allows excess torque to escape through the unloaded wheel.”
I’m quite sure that he is very fast. I’m also quite sure that his tunes are very good, probably better than mine. However, high skill at a task doesn’t mean necessarily mean high technical knowledge. There is a reason why Chuck Yeager never became an astronaut.
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Look, I said I’m not getting into the nitty gritty. That just takes too much time. Your meaning behind the term “open” wasn’t particularly clear when using it. As for my “badly worded” post, I put it as simply as possible. That explanation works quite well for those who don’t understand how the settings affect the car. If I want to get on the power earlier, I raise the acceleration diff. If I want to enter at higher speeds and hold a tighter line while doing so, I lower my decel. I don’t think the “real” mechanics of tuning settings matter much here, as some of the fastest tunes have the most unrealistic settings.
Neither would I want to. However, when people are using the same terms to relate to different things and in some cases those terms are opposite of reality, it tends to make the conversation more confusing.
An “open diff” is an actual mechanical device. I stated that setting the diff at 0% basically turns it into an open diff, which is true. The effect on accel or decel is different, but it is still an open diff.
Yes, but some important details with the understanding were wrong.
And here is a sticking issue. Raising the accel setting on the diff doesn’t really allow you to get on the power earlier, it allows that power to drive the car out of the corner “harder.” You can get on the power at the exact same time with a completely open diff (setting at 0%), but the power will be spun away through the inside wheel. Some understanding of what each setting does can be helpful.
I’ve said many times that there is a line where Forza goes from being an excellent simulation of real world physics to being just a game. That is not in dispute.