MadUsa1

I'm looking to improve the steering response and feel of my 2006 Hawk Eye STI.

My main complaint with the OE setup is the slow reaction to initial steering input and the lack of feel around the straight ahead.

I also have a 2010 Clio 200 Cup, which responds to steering inputs with ridiculous zest. I'd like to get a bit of that into the Scooby.

Will the litchfield Type 25 handling kit, combined with the OE dampers and springs improve the situation?

Thanks!

Toffee

iTrader: (3)

I have an 06 hawk, I added the Whiteline ARBs & ALK which did improve things alot, I go playing with a Clio that is stripped out for trackdays and I can stick with it through any twistys

However the Clio has a shorter wheelbase so you will never match its ultra fast turn in feel, you will have to work harder in a Scoob in the really tighter stuff

MadUsa1

thanks for the feedback. In what way did the ARBs and ALK improve things? Is the turn-in sharper? Is there more feel to the steering around the centre? Is the initial steering response more eager?

Cheers!

Oh, and is it easy to fit?

Toffee

iTrader: (3)

The turn in response is not massively different, the ARB's are adjustable so these can be moved to help things (slightly) the steering feels slightly heavier and there is more feel to what is actually happening. The biggest gain I find is that once the front starts to lose grip (understeer) I can feel when its about to happen rather than realising it has already happened > there is juster better comunication to your hands of what the tyres are doing

I have just purchased a coilover kit & rear toe kit to improve the suspension (improve track lapping times and hopefully eradicate understeer) if you are keen in ultra fast turn in (I am no expert) I think the biggest gain will be had in adjustng/increasing your "toe out" and "castor points" this is what I will be working on late January > early February, but as yet I have no experience on the changes yet

MadUsa1

I've heard steering feel and steering response is greatly impacted by increased caster, have you ever played with this?

Arnie_1

There is quite a bit you can do to improve the steering reaction, get (some) feel and improve overall handling of your STi.

In general, you want to focus on removing slop from the standard bushings, improving suspension geometry and control roll. A little side note, you can improve steering feel but its never going to have the steering feel of, say, an Elise.

Caster

An increase in Caster will provide more feel, more steering self-centering, more straight line stability but most importantly dynamic negative camber on turn in as well as "pushing" the inside wheel down (providing more grip to the inside wheel).

You can do this by installing a Whiteline Anti-Lift Kit. It provides .5 deg static positive caster and due to the stiffer bushing up to a degree, deg and half of dynamic caster. (Under braking and acceleration, the stock lower control arm bushings flex tremendously under braking and acceleration leading to very different caster angles under load). It also changes the anti-lift characteristics, reducing the anti-lift over stock.

You can also change caster up top using a rotated camber plate or the Whiteline Com-C upper mount. You get the benefit of a stiffer mount (less geometry change under load) as well as having the the strut mount shoved farther rearward adding caster.

Bushings

The stock bushings are pretty much mush, concerned more with reduced NVH rather than performance. The softer bushings, like in the ALK example above, contribute to sloppy dynamics, less feel and dramatic alignment angle changes under load.

Steering Rack Bushings

Though the newer racks are better reinforced than previous racks, the bushings are still soft, especially with a few years on them. Install uprated poly Whiteline Steering Rack Bushings to remove the slop.

Lateral Link and Trailing Arm

Steering just doesn't happen at the front end. The rear end of the car contributes to the steering of any performance car and the Impreza is no different. By installing stiffer bushings in the Trailing arms, Lateral Links and Rear knuckle the steering becomes more immediate and the tail more lively. You can use STi Trailing arms with pillow ball bushings and STi lateral links (with pillow ball and/or Group N rubber bushings). Or you can keep your OEM arms and install STi Group N bushings or Whiteline Plus bushings. After I installed the STi trailing arms and lat links on a car I was pretty amazed at the difference. The car rotated as if we had installed a larger rear swaybar. Steering was immediate. There was a slight increase with the pillowball bushings but I've installed Group N and Whiteline Plus setups and the NVH is less with a similar performance level.

Anti-roll Bars

Installing an ARB will not only reduce roll and increase grip but it will also contribute to the steering immediacy and car rotation. Fitting a larger rear bar will do that for you. Ideally, I prefer a larger front(to control dynamic camber loss) and rear bar (to tune rotational bias). I suggest either 24mmF/24mmR, or 22F/24R. Both adjustable so you can fine tune your handling bias to your setup and conditions. If you decide just to fit a rear bar, use a 22mm adjustable.

Alignment

Definitely speak to a qualified performance shop like Litcho to determine the best geometry setup for your needs. Alignment is one of the most important things, the basic building block, of getting your car to turn properly. The OEM specs are crap and the range of tolerance wide. You want a precise a alignment that maximizes the grip fro the setup and conditions you drive. Alignment is a pretty personal thing so I'd rather not suggest any specific numbers.

Arnie_1

Install of most of the parts isn't too tough for an experienced shade tree mechanic. All things installable on your back in the garage (with the exception of pressing in bushings if you go the Group N route). I've installed all the above parts at home with my basic hand tools, jack and jackstands.

MadUsa1

Great stuff arnie, very helpful post! Will get on and order the bits n pieces shortly.

Can I assume the standard STI springs and dampers are ok with the above items attached or should I budget for a decent set of coilies as well?

XRS

The T25s come with a set of AST adjustables.

Arnie_1

MadUsa1 - very welcome. Let me know if you need help with the specifics as there are some choices between the specific parts (3 different flavors of ALK, for instance).

Standard STi dampers and springs are fine with the above parts. You can certainly budget for coilovers at some point if you want to take it to the next level. But use the above parts first, get used to those and see what you feel needs to be improved. I'd personally stick with the stock dampers and, at the most a good lowering spring over a low end coilover.