Understeer Solutions? Sway Bars?

[Draco-REX]

Originally Posted by Gopherboy6956

I would be perfectly willing to go to something like -2.5 front, -2 or -1.5 rear.

What is the advantage of that, though?

As you enter a turn and transfer weight to the outside tires, the body rolls to the outside as well. Because our cars have a Machpherson Strut design for the front suspension, every degree the body rolls translates into a degree of positive camber added to the outside tire PLUS a fraction due to suspension compression. In the rear, you have a similar result, but the rear suspension design gains negative camber under compression, so it isn't a full 1:1.

What's happening in your situation is that you're quickly going positive up front while the rear is staying closer to square with the road. So to counteract this, you need more negative camber up front so you can afford to lose some to body roll. Reducing the rear camber will nudge it further into positive and reduce rear grip slightly, to assist with rotation.

[Calum]

Now we just need @Sam Strano saying he needs more front spring rate, and @ZDan to chime in about struts and camber gain.

[Calum]

I'll add my opinion to, not because it matters but because I have one...

I, also, don't think a rear sway bar is the right way to go, not until you get the alignment sorted at least. If you find you're still understeering then I'd look at the softest adjustable bar available. This car really doesn't conform to the norms when it comes to suspension tuning.

[Gopherboy6956]

Originally Posted by Calum

I'll add my opinion to, not because it matters but because I have one...

I, also, don't think a rear sway bar is the right way to go, not until you get the alignment sorted at least. If you find you're still understeering then I'd look at the softest adjustable bar available. This car really doesn't conform to the norms when it comes to suspension tuning.

If any bar, I would look at an adjustable 16mm rear one.

[Calum]

Originally Posted by Gopherboy6956

If any bar, I would look at an adjustable 16mm rear one.

I forgot, I don't think I saw any mention of toe settings. What are you running?

[Gopherboy6956]

Originally Posted by Calum

I forgot, I don't think I saw any mention of toe settings. What are you running?

0.

This is the sheet:

[Calum]

To my understanding, a touch of toe in up frontmight help, and would be more stable at highway speed. It should make the front tires wear better to consider the amount of deflection in the stock bushings. But your present settings seem to be in the generally accepted sweet spot.

[autobrz]

Originally Posted by Draco-REX

Sway bars will reduce body roll which, in turn reduces camber loss. However, by linking the two sides of the suspension more firmly, you're essentially shifting more weight to the outside tire, off of the inside. This can actually reduce the overall available grip. Often this loss of total grip is balanced by a more controlled suspension. But a well set up and more independant suspension will have a greater ultimate grip level and be better behaved over rough surfaces.

This.

More independent rear suspension on a RWD car is faster...

[Draco-REX]

Originally Posted by Calum

To my understanding, a touch of toe in up frontmight help, and would be more stable at highway speed. It should make the front tires wear better to consider the amount of deflection in the stock bushings. But your present settings seem to be in the generally accepted sweet spot.

I'm a big fan of 0 toe all around.

A little bit of toe OUT up front will improve turn-in feel. Toe IN is good gor high speed stability, but hurts feel.

In the rear, tow IN will help reduce "snap" oversteer. This is good for track use. Toe OUT in the rear will lead to oversteer. Only good for AutoCross on tight courses and Gymkhana, not considered safe for street use or track use.

So I just like 0 all around. It's also much nicer to the tires too, especially when running aggressive camber settings.

[Draco-REX]

I'm also one of those heathens that thinks SAI isn't a big deal. But that's for another discussion.

[ft_sjo]

Originally Posted by Gopherboy6956

If any bar, I would look at an adjustable 16mm rear one.

The problem with adjustable bars is it effects the drop link angle which skews the curve of the bar.

For the price of a bar, and the 10 minute installation, just go get one and try it out. It's a no-brainer.

[Mars2]

when looking in to rear sway bar you have to think that our torsen type Lsd really don't have to have that rear inside wheel spinning in the air. big loss of power their. then you have to upgrade to clutch type lsd so more money again. I would go for stiffer back spring's

[7thgear]

Originally Posted by Draco-REX

Because our cars have a Machpherson Strut design for the front suspension, every degree the body rolls translates into a degree of positive camber added to the outside tire PLUS a fraction due to suspension compression.

not quite that dramatic..

this is why having your a-arms below parallel and shock travel is important..

macpherson strut properly setup can maintain a proper contact patch while the chassis is rolling within managable levels






also castor...

[Racecomp Engineering]

Originally Posted by 7thgear

not quite that dramatic..

this is why having your a-arms below parallel and shock travel is important..

macpherson strut properly setup can maintain a proper contact patch while the chassis is rolling within managable levels






also castor...

Sure helps when your front spring rates are relatively firm.

Especially when the rates overall aren't super high (i.e. with springs or softer coilovers like these).

- Andy