Best setup chassis guide for real race and racing games

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Rustem 1988
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Best setup chassis guide for real race and racing games

Post by Rustem 1988 » Fri Jan 19, 2018 7:35 pm

Hello, I am Rustem. What setup chassis guide are best for real racing and racing games?

Rodak
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Joined: Wed Oct 04, 2017 2:02 am

Re: Best setup chassis guide for real race and racing games

Post by Rodak » Fri Jan 19, 2018 10:12 pm

"How to Make Your Car Handle" by Fred Puhn. "Tune to Win" by Carroll Smith.

Rustem 1988
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Re: Best setup chassis guide for real race and racing games

Post by Rustem 1988 » Tue Jan 23, 2018 3:58 pm

What physical parameter determines the response of the car? Why increase the stiffness of the springs and tires enhances the response of the car?

Greg Locock
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Joined: Fri Jun 29, 2012 11:48 pm

Re: Best setup chassis guide for real race and racing games

Post by Greg Locock » Tue Jan 23, 2018 8:40 pm

Depends what you mean by response, but I suppose if you mean yaw velocity gain (deg/s/deg steer) then to make it more responsive you need more force at the tires for a given steer angle. So that's sort of why stiffer tires help. Stiffer springs won't always make the car more responsive. They will probably give a better subjective feel for the steering.

Anyway, the long and the short of it is that you are asking 'why' instead of 'what', so you need a textbook. There are several, I'd say Race Car vehicle Dynamics by Milliken is probably the one that is generally recommended, not least because it has a handy lookup table of 'what affects what'.

Tim.Wright
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Re: Best setup chassis guide for real race and racing games

Post by Tim.Wright » Wed Jan 24, 2018 7:55 am

I've found the word "response" when used in the context of subjective feedback is a dirty mix of objective metrics including both gains and delays of yawrate, lateral acceration and roll as well as steering torque to a lesser degree.

Often a driver will tell you the car is more responsive with stiffer springs simply because it reaches its steady state roll angle quicker.
Not the engineer at Force India

Greg Locock
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Re: Best setup chassis guide for real race and racing games

Post by Greg Locock » Wed Jan 24, 2018 11:24 am

It's a bit like higher roll centres at the front. Very hard to detect the effect objectively, but subjectively the torque build up is much better. In an on centre test (ie swaying the SW back and forth) the effect is probably measurable (if inside the noise) , but it doesn't show up in a normal swept steer.

Rustem 1988
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Re: Best setup chassis guide for real race and racing games

Post by Rustem 1988 » Thu Jan 25, 2018 7:47 pm

Thanks.

If the car roll in the corner, then camber on the outside absolute value less than inside. How different angles of camber affect the behavior of the car in a corner How change lateral force and camber force? If camber positive, than lateral force decrease? And if negative camber angle no ideal then lateral force increase little?

Rustem 1988
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Joined: Tue Sep 05, 2017 10:38 am

Re: Best setup chassis guide for real race and racing games

Post by Rustem 1988 » Sat Jan 27, 2018 7:15 pm

If the car which travels in a straight line to exert a lateral force, the camber thrust to the left and right will be the same?

Rustem 1988
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Joined: Tue Sep 05, 2017 10:38 am

Re: Best setup chassis guide for real race and racing games

Post by Rustem 1988 » Sat Jan 27, 2018 7:20 pm

The direction of the camber force on right and left wheel is different?

Tim.Wright
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Re: Best setup chassis guide for real race and racing games

Post by Tim.Wright » Sat Jan 27, 2018 9:45 pm

You are right that in a straight line the camber thrust from the left and right wheels will oppose each other.

You are also right that in a corner the left and right camber thrust effects will be different. But its a very small effect because there is already a large difference in lateral force between the outside and inside wheels due to the vertical load transfer. The difference in camber thrust is only a small percentage of the total lateral force difference left to right.

There is problem in your terminology though - I think you are mixing up camber angle (wheel tilt relative to the chassis) and inclination angle (wheel tilt relative to the ground).
Not the engineer at Force India

Greg Locock
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Joined: Fri Jun 29, 2012 11:48 pm

Re: Best setup chassis guide for real race and racing games

Post by Greg Locock » Sat Jan 27, 2018 10:18 pm

The geometrical effect there could be called camber recovery in roll. So if you roll a live rear axle car the wheel inclination relative to the road does not change, you have 100% camber recovery. Meanwhile the independent front suspension probably travels about 50mm per g of cornering, and the vehicle rolls about 4 deg/g. typical front camber gain is -30 deg/m, so the outside wheel relative to the ground rolls 4 degrees out due to the car rolling, but back in by 1.5 deg due to the kinematic camber gain. The inside wheel rolls 4 deg out PLUS 1.5 deg.

You might wonder why people don't use 100% camber recovery on an independent suspension. I've actually given a partial answer above, but that is why you need a textbook not a tuning guide.

Rustem 1988
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Re: Best setup chassis guide for real race and racing games

Post by Rustem 1988 » Tue Jan 30, 2018 2:01 pm

I want to do bycicle model of car in the corner with cornering and camber force and I want to do equations for forces and moments. Whether camber thrust to affect the slip angle of the wheel? That is, the ratio of lateral and longitudinal wheel velocity minus the steering angle?

Greg Locock
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Re: Best setup chassis guide for real race and racing games

Post by Greg Locock » Wed Jan 31, 2018 6:29 am

I'd ignore it for a bicycle model.

Rustem 1988
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Re: Best setup chassis guide for real race and racing games

Post by Rustem 1988 » Wed Jan 31, 2018 9:18 am

I want to know how camber force affects on understeer and torque balance.

DaveW
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Joined: Tue Apr 14, 2009 11:27 am

Re: Best setup chassis guide for real race and racing games

Post by DaveW » Wed Jan 31, 2018 10:25 am

Rustem 1988 wrote:
Wed Jan 31, 2018 9:18 am
I want to know how camber force affects on understeer and torque balance.
I think you have good advice, Rustem. If you don't like it, question your model.
If you require answers for a real race vehicle, you may need to add "installation" stiffness (Sprung mass is seldom a monolith).