Steering feedback-Caster angle

From soft stock to hardcore track, what do you use?
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BETEK
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Steering feedback-Caster angle

Post by BETEK »

With swapping sides the front upper control arms, feedback from steering wheel is increasing.
Because the caster angle became more.
Also one other advantage on ej9 is that the returning of steering wheel in straight line is more quickly than stock setting.
I did the swapping recently and so far I like the feedback of steering wheel. It is not dramatic change but it is a little improvement of feedback.

Here is a nice article about caster angle and other car alignment elements:
http://www.tirerack.com/tires/tiretech/ ... p?techid=4

Caster

The caster angle identifies the forward or backward slope of a line drawn through the upper and lower steering pivot points when viewed directly from the side of the vehicle. Caster is expressed in degrees and is measured by comparing a line running through the steering system's upper and lower pivot points (typically the upper and lower ball joints of an A-arm or wishbone suspension design, or the lower ball joint and the strut tower mount of a McPherson strut design) to a line drawn perpendicular to the ground. Caster is said to be positive if the line slopes towards the rear of the vehicle at the top, and negative if the line slopes towards the front.

Image


A very visual example of positive caster is a motorcycle's front steering forks. The forks point forward at the bottom and slope backward at the top. This rearward slope causes the front tire to remain stable when riding straight ahead and tilt towards the inside of the corner when turned.

Caster angle settings allow the vehicle manufacturer to balance steering effort, high speed stability and front end cornering effectiveness.

Increasing the amount of positive caster will increase steering effort and straight line tracking, as well as improve high speed stability and cornering effectiveness. Positive caster also increases tire lean when cornering (almost like having more negative camber) as the steering angle is increased.

What's the downside to positive caster? If thevehicle doesn't have power steering, a noticeable increase in steering effort will be felt as positive caster is increased. Other than that, the effects of positive caster are pretty much "positive," especially increasing the lean of the tire when the vehicle is cornering while returning it to a more upright position when driving straight ahead.



Another article about car alignment elements:
http://yospeed.com/wheel-alignment-expl ... aster-toe/
Image
Caster is a bit harder to conceptualize, but it’s defined as the angle created by the steerings pivot point from the front to back of the vehicle. Caster is positive if the line is angled forward, and negative if backward.

Typically, positive caster will make the vehicle more stable at high speeds, and will increase tire lean when cornering. This can also increase steering effort as well.

Most road vehicles have what is called cross-caster. Cross castered vehicles have slightly different caster and camber, which cause it to drift slightly to the right while rolling. This is a safety feature so that un-manned vehicles or drivers who lose steering control will drift toward the side of the road instead of into oncoming traffic.

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saxophonias
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Re: Steering feedback-Caster angle

Post by saxophonias »

I had been reading about it. How much did it cost?

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BETEK
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Re: Steering feedback-Caster angle

Post by BETEK »

Nothing. I did it myself.
I just changed sides of front upper control arms.
It is easy job.
You just need pliers, hammer, jack and 10mm, 14mm, 17mm wrenches.
Optional will be good to have ball joint remover

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saxophonias
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Re: Steering feedback-Caster angle

Post by saxophonias »

Does it feel any heavier?

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BETEK
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Re: Steering feedback-Caster angle

Post by BETEK »

Yes it has little heavier feeling.

hondaNickx
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Re: Steering feedback-Caster angle

Post by hondaNickx »

I have been driving with it for a few years now ,and i love the better steering respons it gives.You just need to swap the left en right front upper control arm . Left goes right and right goes left.Should increase the caster from the stock 1°40' to 2°40' which is the max of stock specs.I didn't noticed any heavier steering ,but i also have power steering .
Quote from Endyn:"The combustion chamber is a better shape than the DOHC.So don't chunk those 1.6 SOHC engines, they can make really good power. For a pure performance application, regardless of application, I'd choose the SOHC. No bull!"

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saxophonias
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Re: Steering feedback-Caster angle

Post by saxophonias »

Is it true that by lowering the suspension the caster angle changes to the worse?

hondaNickx
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Re: Steering feedback-Caster angle

Post by hondaNickx »

saxophonias wrote:Is it true that by lowering the suspension the caster angle changes to the worse?

No , that's the camber angle . ;)
And yes whenever you lower the car the camber gets more negative.
Quote from Endyn:"The combustion chamber is a better shape than the DOHC.So don't chunk those 1.6 SOHC engines, they can make really good power. For a pure performance application, regardless of application, I'd choose the SOHC. No bull!"

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Dodo Bizar
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Re: Steering feedback-Caster angle

Post by Dodo Bizar »

I would say yes.

Lowering indeed increases camber to negative (that I love about Honda Civics).
But yes it also changes caster towards negative. I lower my cars a lot and on different height settings. With the EJ1 chassis I went so low that caster became 0. That means the self-centering of the car on a straight line is worse. I actually love that and consider that a good thing... :!: I want my cars to steer lightly and immediatly, up to the point of slight oversteer as the EJ1 actually does (though toe-setting is very relevant as well). My car was considered tricky by an experience Nurburgring driver who always complained about his understeering Civic :mrgreen: .

I recently put the car back up 1.5 cm since it had 5.5 cm ground clearance. Now we are back at 7 cm clearance and caster is almost 0.5 degrees now. Which compared to zero is a huge difference in the self straightening of the steering wheel.

hondaNickx
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Re: Steering feedback-Caster angle

Post by hondaNickx »

I have lowered my car on several different coilovers and i always checked the alignment specs when i got it aligned.
The caster never changed (not noticable though).
From -7cm lowered up till -4cm lowered ,from -2.5° up till -0.5° negative camber , caster always remained the same.

It only changed when i changed my front lower control arms for others ones,because some of the bolts also hold the subframe.So by loosing those bolts the subframe had the chance to get out of spec.
Quote from Endyn:"The combustion chamber is a better shape than the DOHC.So don't chunk those 1.6 SOHC engines, they can make really good power. For a pure performance application, regardless of application, I'd choose the SOHC. No bull!"

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