Where do you think this game falls short in physics?

Forza Motorsport Legacy Motorsport FM7 Discussion
1

Personally for me, it’s downforce. As far back as I can remember Forza has never had a good downforce model. Cars with no aero drive pretty much the same as cars with the aero package, and production cars handle similarly to race cars. Tuning aero only produces the most basic effects; increasing it decreases top speed and increases high speed cornering ability, and vice-versa, but it doesn’t change the nature of the car’s handling like it should. Cars with high aero should almost never have snap-oversteer or frankly any oversteer, yet no matter how much or little aero you put on a car in this game it will still oversteer the same amount. In fact, putting aero too high should produce slight understeer as the tires will be overloaded from the downforce, but it never does this. This problem is blatant with GT cars and Prototype cars, which will lose grip at any turn when they should feel completely stuck to the road.

Another big one I’ve heard reviewers talk about is tire flex, i.e., the way the tires perform through corners and under throttle. Inside Sim Racing called Forza’s driving feel as “flat, like you’re just driving on top of the track” and I have to agree with them. I think that’s why some of us have felt like the cars drive on rails and don’t have the nuances you’d expect from previous games. It does seem like the connection between the car and the track is very shallow, but this is forgiveable for the type of game Forza is. To get realistic track physics, they would have to use a combination of universal physics with track-specific physics that factor in location, time of day, and weather conditions, as well as surface types and smoothness.

Any other areas where you think the physics just don’t stack up to other games? I know that Forza isn’t supposed to be a simcade but it’s interesting to discuss something which most players don’t even factor in when buying racing games.

2

If you put a wheel on the grass in a braking zone, you don’t get thrown off the track like you do in Gran Turismo Sport, that’s one thing I noticed recently.

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3

This^^^ also braking and turning on the white line, especially in the rain doesn’t seem to effect your car as much. Downforce is simulated well in this game imo and the suspension in general is simulated pretty damn well. Crash physics in single player are spot on but in multiplayer they are extremely broken. The damage model in general is poor. Once you get damage it’s simulated very well but you have to really smash the car to even get any minimal damage. In short the cars are too tough. Also active aero isn’t simulated and not are airbrakes which is a shame.

Apart from these Forza nails it imo.

4

This is driving me nuts. Maybe I’m not remembering correctly but I could have sworn in FM4, 5 and 6 touching the grass would suck me off the track. Perhaps not to the same level in each game and definitely not to the extent like you point out in GTS but the effect was definitely there and seems to be lessened(or nonexistent)with FM7. I also remember it being more difficult to free myself from a wall. Previously if you just grazed, we’d stick to it like a magnet but in 7 we seem to bounce off as if they are made of rubber.

5

Not sure I’d agree about the physics.

As far as I can tell the aero does have the correct affect. It increases the level of lateral grip of the car particularly at speed. All aero has a limit and if you exceed it then you’ll get understeer and/or oversteer anyway. Just watch F1. The most advanced aero in racing and yet you’ll see plenty of understeer and oversteer from most of the grid. Whatever the car is capable of we all still push beyond its limit at some time.

Tire flex is an odd one. I’ve been driving for ever and can’t really say it’s something you notice. Forza does respond to changes in tire pressure so in other words firmer or softer tire walls so I guess it’s factored in. Modern crossply tires are designed to maintain the correct contact patch under lateral load so I guess flex isn’t such a factor. Old radials with massive profiles would roll around a lot but these aren’t something we encounter.

6

Not enough quantum field theory… But the driving still feels good, which is the important thing.

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7

I also noticed a more pronounced aero effect when make large incremental changes. To me, running full aero seems to give much more stability than I noticed in other titles. Conversely, I get noticeable under or oversteer as the difference in front and rear spoiler settings increases. As I change the aero setting and adjust the suspension, it does seem to respond as expected.

As for tires, the main thing I have noticed is the base tire pressures seemed to be a little higher to reach the 32 psi range in race. I am by no means a master turner, so I will defer to the resident community experts on this.

8

As funny as it sounds, the crash models. I still look forward to the day where I get a GRID crash style system. I like the concept of racing a car like it’s made out of egg shells. LOL

9

Tyre temperature, it seems like only surface temperature is simulated and core temperature plays no part. Surface can get severely overheated but will cool off very quickly and has no effect on the core temperature and air pressure of the tyre.

10

Let me preface, I think Forza physics are gloriously FUN. That being said, I think the biggest issue with Forza is the complete lack of “danger.” You can jump in a 600hp RWD car, completely mess up a corner and there are no consequences as you are instantly a drift god. I don’t want Forza to be PCars 2 (which is amazing in its own way) but I wish there was more…urgency when you make a mistake.

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11

On a wheel not so much and if you run SIM steering not at all imo.

Edit: but with normal steering, yeah, drift God mode is activated.

12

This is good to know, I am waiting for Black Friday to get a fanatec setup for PCars 2 and Dirt Rally, but knowing it’ll make a difference in Forza is pretty cool, thanks

13

Having met the physics designer for this game, I can tell you there was tremendous effort in getting it right over the last several games. This guy was not just a physics guy, and a developer, but also races actual cars on real tracks. Very nice guy too.

I’m going to try and recall this conversation as well as I can but (if he reads this) forgive me if I leave out a key parts as this was just over a year ago.

Turn10 partnered with Pirelli Tires during the development of Forza 5. They spend countless hours sorting mathematically how a tire’s grip quotient changes by tire pressure, temperature, slip angle, direction of movement, alignment. load and tons of other variables. Pirelli actually supplied data from REAL tire tests to help Turn10 get their models as accurate as possible. They also threw in different levels of grip in different parts of the track at different temps, changes in air pressure, and tons of other things.

They did admit that they had to “simulate” some effects for performance and playability concerns but everything he told me made perfect sense.

As a car tuner in real life and avid tuner in Forza, let me assure you that the models are very close and making changes to damping, spring rates, alignments, ant-roll bars can have dramatic effects on how a car handles. As in real life, you can’t just slap a wing and a splitter on a car and expect it to drive correctly. If you do not understand what you are doing you can actually make the car much slower than it was before.

I spend hours tweaking and testing my tunes in Forza for each car to get them “just right”. Sure there are some cars that require a bar setting or alignment that has me scratching my head thinking “yeah, this would never fly on a real car” but that’s pretty rare.

I’m droning on now so I’ll just close with this. Don’t oversimplify what Turn10 has accomplished with their physics engine. It’s very good and one of the main reasons of their success over the last decade is that the cars “feel” right. Personally I think they dialed in too much natural understeer into the cars this time around and while this will definitely make the cars slower around a track, it makes them much easier to drive.

(to the guy that was complaining about adding aero to the car resulted in over/understeer. Use your anti-roll bars to get you car set up with the right over/understeer you want first. Then add downforce.)

Scott

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14

Inside sim racing uses a wheel exclusively while forza is obviously more biased towards controller users. Tire flex is definitely there and the suspension is reacting to things but when you use a wheel in forza almost none of the suspension forces are sent to the wheel so thats why it feels flat. Its something that i really hoped wouldve been added to the game considering they supposedly laser scan the tracks. Maybe forza 8…

15

Unfortunately I believe this is down to the lateral load of the tires not being translated well in the FFB. Inside SIM Racing also complained about the tire flex in F1 2017 saying that it felt like driving on plastic not rubber. Trouble with inside SIM Racing when it comes to games like Forza is they feel it’s not simulated enough.

16

I pretty much only e-c class car’s and never understood why the aero had a huge impact going 50mph. But they do.

17

I disagree on the point regarding aero. If you slap aero parts on a real Ford Fiesta, even if you do everything right, the difference is not going to be pronounced. It’ll be subtle, just as it is in Forza.

With the dedicated winged cars in Forza you can absolutely sense that you have to approach them differently. As speeds increase your ability to adjust balance via load transfer becomes more and more muted and your front to rear aero balance becomes more important than even the spring rates.

Adding 150 lbs of downforce to a 3000 lb car will not be as easy to notice as adding 500 lbs of downforce to a 1500 lb car designed for it to begin with.

18

Just expressing my opinion gathered from a bit of seat time. I think the race tire compound is not sticky enough. My current daily driver tires are the Michelin Pilot Super Sports. My last two sets of track day tires were the Yokohama A048s and Hankook Z214 C51 slicks.

The Michelin PSS’s are a common oem tire for cars like the Porsche 911. They’re about up there for street use and can straddle the line between everyday commute and occasional track use. The Yokos are basically street legal semi-slicks and the Hankooks are a cheaper mid-compound slick that lasts 2 or 3 dual-session track days before getting greasy.

The game simulates the difference from street tires to sport tires quite well but the difference between sports tires and racing slicks isn’t as significant as it should be.

And this is comparing A048s to a Hankook C51 compound. We’re not even venturing into the Hoosiers yet.

19

To be honest, my only gripe with the physics, relates to an overabundance of grip, on the majority of non aero cars; regardless of tyre.

20

Here’s the thing:

Most people in this forum, including myself, have never driven on a track at racing speed - without that reference, there’s not really any way to know where the physics fall short. All I know is I’ve been playing a lot of both FM7 and GT Sport and the physics couldn’t be any more different between the two. Which one is more “real”? I have zero idea, but I prefer Forza’s physics.