The online racing simulator
The need for an accurate steering ratio; realism is at stake! :)
(108 posts, started )
The need for an accurate steering ratio; realism is at stake! :)
Heya,

What a dramatic thread title!

A short point I want to make where us simracers can cheat a bit; the steering ratio. Assuming we have the right Fanatec or Logitech wheels, we can use anything up to 900 degrees on our steering wheels. Depending on the car we drive in the sim, we can set the steering lock somewhere between 15 and 35 degrees, depending if its a F1 car or road car for example.

The ratio between the rotation you use on the wheel and the value you set in the car setup is quite critial. A Corvette Z06 ''supercar'' has a steering ratio of 17.2:1. This means you have to turn the steeringwheel 17.2 degrees for the front tires to turn one degree. I also know a modern single seater car with a 14.5:1 ratio. Perhaps forum users know a few more real life values. In order to get somewhat correct steering sensitivity, it makes sense to copy these values in your simracing hobby. Here is how.


17.2:1 real life steering ratio: Divide your wheel setting, say 900 by this, so 900 / 17.2 = 52.3 degrees. This is the *total* steering, so you have to take half of this: 52.3/2 ~ 26 degrees. This is you car setup value.

For a single seater, its unlikely that they have 900 degrees of steering. Perhaps you know that the car has a 14.5:1 ratio and that the maximum steering is 17 degrees one way, making 34 degrees total. Then you have to set the wheel limits to 34*14.5 = 493 degrees, and set the car setup to 17.

That makes sense. The reason I'm posting is that plenty of people aren't comfortable with 900 degrees. Yet they do want 34 degrees of lock in the car setup. Say you use 450 degrees on your wheel and 34 in the car setup, this is a whopping 6.6:1 steering ratio! That is almost 3x more sensitive than an already sensitive Corvette.. Your drive will be very sensitve, twitchy and unrealistic as a result.

Its much much better to learn how to use 900 degrees on cars that do actually have this much in real life; learn how to re-grip the wheel. Its tricky but driving with a rack that is over 2x too sensitive throws any ''Its a simulation!'' arguments out of the window!

See attached table for some guidelines.
Attached images
steering.GIF
#2 - G!NhO
Ah thanks, great information and i never knew about this.

So you recommend 26 degrees with 900 degrees wheel with your Corvette?
i am pretty sure you are trying to say, ues more 900 degree cars in lfs...but i am just out of school so i diddnt want to think about math
#4 - G!NhO
It's also about rFactor, and racing sims in general.
For the record - Dallara F3 car has about 450° of steering wheel, and lock-to-lock at the wheels is about 36°. So the steering ratio would be 12.5:1.

Lotus Exige (and therefore probably the Elise, as one is a cheap parts bin rip off of the other) is fairly similar, probably around the 13 to 14 area.
As an owner of one of those cheap parts bin rip-offs, I can tell you from the manual that it is 828degrees lock to lock. I doesn't say what the max steering angle is unfortunately.

When I'm driving it though, I only ever need to take both hands off the wheel in the most extreme hairpin or when parking, you can cross your hands for 99% of corners.
As an owner of one the cheap parts bin rip-offs, I can tell you that ours doesn't have that much lock!

I think it's probably around 50° lock to lock...
#8 - G!NhO
What car do you mean with "one the cheap parts bin rip-offs"?
50 is TINY. that is like well less than 90 degrees which having 90 on each side is still tiny, even though it is 180, so 50 must not be true!
Quote from logitekg25 :50 is TINY. that is like well less than 90 degrees which having 90 on each side is still tiny, even though it is 180, so 50 must not be true!

I think he means the number of degrees the actual tire and wheel turn not how many degrees of rotation that the steering wheel turns. He said the wheel turn being like 450°.
oh few, that would be horrible
Not many cars in LFS have 900 degrees of steering.. Now who wants to turn the wheel 900 degrees in a formula car to get full lock

I know that's not what you meant, but you make it sound a bit like it
thats why I attached a table with some hints to decent settings, of course single seaters don't use 900. Still, if you use like 20 degrees in the car setup with 270 degs on your wheel, its likely to be 2x too sensitive.
Well my wheel always matches the wheel in LFS 1:1.. Doesn't that seem reasonable?
hehe Not necessarily, I believe the amount of graphical steering wheel movement is the same regardless of your car setup steering lock; the ratio could still be anything from very wrong to perfect!
Quote from RasmusL :Well my wheel always matches the wheel in LFS 1:1.. Doesn't that seem reasonable?

That's not really what it's about.

It's about how far the wheel has to be turned to turn the actual tyre by 1 degree.
The wheel match hasn't really got influence on that, it'll only screw up the rest of the FF.
Well, that really depends on the setup, and I never make those myself
I mostly drive FBM and FOX, both have 450 degree lock-to-lock. Maximum lock is 20 degrees on the wheels, and most setup uses this. A few use 19 or 17 degrees.. Seems good to me.
Bookmarked! I'm gonna try this when I get my Porsche wheel.
Ever since I got my G25 I always ran 540 degrees of rotation. In the FO8 I ran 20 degrees of lock. I came back to LFS after running iRacing a bit (and roadracing motorcycles IRL) and 540 felt a bit slow, so I went to 450 degrees.

As a matter of fact, 540 rotation and 20 lock on the FO8 always felt a bit slow to me but I was used to it. It gave me some finer, smoother control that I think a lot of my competitors had foregone.
I wish it were as simple as using the 'correct' amount of lock. With my DFP, the force feedback is just too slow when you're trying to correct oversteer in an LX6 with full steering lock. I think the G25 is fast enough, but with the DFP when you're trying to force the wheel faster than the FF motors want to go, it's not a lot of fun.
Agreed, after 30 minutes with the DFP I almost literally thew it out. Seems the new DFGT is a tad better, at least less restrictive when you turn it fast.

In a way the G25 is too slow, but I'm not sure if it would get any easier if it delivered true steering forces as well; that would be hard work.. I used to blame the G25s for being slow, which it is.. But at 5x or more power, I'm not sure what would happen either!
Thanks for the info!
Is this is the suggested improvements yet, I totally agree.
Quote from G!NhO :What car do you mean with "one the cheap parts bin rip-offs"?

The Exige. It's an Elise with a lid and some tacky bodywork nailed on, plus a few more ponies and some stiffer suspension. Quite quick though in a lethargic sort of way.
Oh ok, but is the Elise a good car as my dad might be buying one (probably 10% chance but whatever ), its one of lower price range like ~10K euro and from about 1998. He needs a cheap car that doesnt cost alot of insurance and road tax, and it has to be very realiable unlike a Jeep.

The need for an accurate steering ratio; realism is at stake! :)
(108 posts, started )
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