Strut bars Important?

[aaronng]

x2
Responses like Actionman's make people afraid to ask questions

I put all 4 strut bars on my EK sedan when I first got it and it made a hell of a difference but say I take a corner quickly and accelerate through the corner the front wheels spin and slide out,that's understeer right? How do ya fix that apart from tyre pressure?

Get better tyres.

[beeza]

Thanks for the responses guys
I was going to put a rear 22mm Whiteline Sway bar on but Dave (Turtle1) did and said it did nothing for ride comfort...
I don't want my ride to be uncomfortable,got da girl in there...

When my tyres wear out I'm gonna sell my rims and get a new set of Rims and better tyres.

[aaronng]

Sway bars reduce roll. They don't reduce ride comfort nor make your suspension stiffer.

[beeza]

My car has been lowered,not the stiffest springs/struts,so I got a bit of roll.From what I've read it will make a hell of a difference over a strut bar. Would you only notice it being there in corners?

It's sounding like it's what I need to reduce understeer and increase oversteer.

[aaronng]

My car has been lowered,not the stiffest springs/struts,so I got a bit of roll.From what I've read it will make a hell of a difference over a strut bar. Would you only notice it being there in corners?

It's sounding like it's what I need to reduce understeer and increase oversteer.

It doesn't increase oversteer. It only reduces understeer. When you increase the stiffness of the rear sway bar too much, it becomes like torsion beam suspension where if one wheel jumps because of a bump on the road, the other wheel will do the same, losing rear grip. This is the "oversteer" that people talk about. But no, it doesn't make your car oversteer like an MR chassis car.

[beeza]

Thanks a lot aaronng
I will talk to Dave and find out exactly how it affected his car since we both got the same cars.I know it will be different since his suspension set-up is different but it's the closest I can get...
It is sounding like a good investment to reduce that understeer.I mean it's no major problem but just say I do take a corner fast (I don't do it much but just say),I dont wanna go sliding nose first into the gutter.So it could save me that repair bill

[aaronng]

Thanks a lot aaronng
I will talk to Dave and find out exactly how it affected his car since we both got the same cars.I know it will be different since his suspension set-up is different but it's the closest I can get...
It is sounding like a good investment to reduce that understeer.I mean it's no major problem but just say I do take a corner fast (I don't do it much but just say),I dont wanna go sliding nose first into the gutter.So it could save me that repair bill

Is your suspension still stock or are you running coils? The effect of a thicker rear swaybar is better when you have stiffer suspension. I found when going from 14mm to 19mm was that the rear felt more willing but would snap from sharp changes in direction if I pushed it really hard. Now with coils, the car is better behaved when pushing hard and is more predictable.

But if you were driving normally at the speed limit and slowing down for the corners, the comfort level would be the same as stock. Maybe even a little better as the car rolls less in sweeping corners.

[beeza]

I've got stock struts and New King springs...

[aaronng]

I've got stock struts and New King springs...

Is the spring rate the same as stock? If it is stiffer, stiffer dampers to complement them will be good.

[loco_corolla]

I have found on my corolla that installing a rear strut brace has slightly increased turn in whilst adding more rigidty to the rear, car feels much stable on daily driving and also feels safer entering corners. But that may just be an expectation created by the psyche, nevertheless i feel a difference.

Maybe honda's react differently i don't know but thats my personal experience, overall i'm happy i bought the damn thing. Plus i got it really cheap

[beeza]

Is the spring rate the same as stock? If it is stiffer, stiffer dampers to complement them will be good.

They are stiffer,Thanks aarronng

[Muzz]

Hey bud, sorry for the slow reply.

[QUOTE=Zilli;1220916]

Im just a little confused here
"wont effect bodyroll at all,wont effect weight transfer/shift either, won't put extra unwanted pressure in the suspension system, and wont effect loads on the tyres in a negative way" then you said - The sole benifit of this is to keep the alignment of the tyres from momentarily changing with large forces from cornering (if the tyres are not affected, what does a change in alignment do to a tyre?)...

When a tyres alignment isn’t at its optimal position, it can’t achieve its optimal grip levels. When huge forces are seen in the suspension arms, well actually where they mount to the car these areas can flex slightly altering the alignment till the large forces are removed/reduced.

This is bad because the alignment will be changing according to the large forces, not just where the suspension is in its range of movement. For example, in hard breaking the front wheels tend to toe out, which would be bad. Stiffening the suspension mount points and using harder/spherical bushings will reduce this effect, and keep them pointing where you set them to be pointing.

The alignment of the wheels relative to the ground is very important, maintaining there correct alignment is very important you don’t want the angles of the wheels moving in ways there not designed to.

With a performance fwd, what we are ultimately trying to achieve, is to get as much grip as we can at the front wheels, then alter the camber of the rear wheels, so that at our peak cornering g’s (max body roll) the outside rear is vertical to the ground where it can make the most grip. This is one reason why there a tons of fwd race cars with a high rear roll rate – to maximise the grip at the front wheels. The rear grip is then regained by altering the rear camber angles for maximum cornering grip.

The above also ties into your question, why is torsional resistance to twist not as important in fwds. The answer being that:
1. It doesn’t help grip at the front wheels any; actually it’s often detrimental to it, and we want as much grip as we can at the front wheels for corner exit so we can accelerate harder, and earlier.
2. Rear grip is added by using rear camber angles for maximum tyre grip in corners, this dosnt take grip away from the front wheels.

……………………………………………………………….


“keeps the roll angles at the front of the car, and the rear of the car more equal” (if the braces wont affect body roll at all why do you mentioned it here?)

As you know during a corner, weight is transferred off the inside tyres, onto the outside tyres (why the outside suspension compresses and inside extends), the total amount of weight that is transferred from the inside to outside depends on 4 things.
1. The height of the centre of gravity above the ground.
2. The force acting on the centre of gravity (cornering g forces).
3. The track width of the wheels.
4. The total weight of the car.

Without changing any of these four things the amount of weight transfer from the inside to the outside will be unaffected. It’s the increase in load on the outside, and the decrease on the inside that causes the cars body to roll. The swaybars and springs determine how much roll those forces produce. (An extremely common misconception is that less body roll means means weight transfer, however the changes in loads on the tyres are the same, the stiffer roll resistance just means they cause less roll)

In a perfect world the cars body has one roll angle for a given cornering force, let’s say its 3 degrease. However this would only occur if the roll resistances of the suspension at the front and rear are equal (pretty unlikely), or the cars body was completely rigid and couldn’t twist torsionally (Not going to happen without lots of unpractical heavy bracing).


What actually happens is the end of the car with the higher roll resistance will twist less than the other end. Lets say the car has a higher roll resistance at the front, it may roll 2.5 degrease, the rear may roll 3.5 degrease, the body is twisting torsionally one degrease between the front of the rear. The total/average body roll is still 3 degrease though, due to the weight transfer.

Increasing the torsional resistance to twist, by adding some proper bracing, will reduce the twisting of the body. Now the front may roll 2.75 degrease, and the rear 3.25 degrease, the body is now twisting half a degree, but the total/average body roll will still be 3 degrease, due to the unaffected total weight being transferred from the inside to the outside.

The effect of the above will alter the weight transfer at the front of the car, and also the rear, but not the total weight transfer from the inside of the car to the outside.

Since the stiff front end of the car is rolling more than before adding the bracing, the weight transfer between the front 2 wheels will increase, and the weight transfer between the two rears will decrease due to the lesser roll angle from before. Hence why you often hear people say “adding this brace made my car oversteer more”.
(More weight transfer at one end of the car will reduce grip at that end).

The of increase in WT (weight transfer) at the front, will be equal to the decrease in WT at the rear, as I mentioned before, the total amount of WT inside to outside wont be effected, only the amounts at the front compared to the rear.

So no mater how much you brace the chassis to increase its resistance to twisting, the total roll angle will not change (what where concerned about), but the differences in roll angles between the front and rear will be reduced, with both front and rear roll angles moving closer to the total/average roll angle.