So let me tell you a little story about my suspension journey with my 06 WRX starting at the beginning.
I love good handling cars. I used to commute 100+ miles a day, and 80 of those miles were through some of the best back country farmland roads around. I used to refer to it as my autocross course, best part there was never anyone on it, and a ton of fun was had at sane speeds. It also gave me an education in suspension design, dynamics, tuning and frustration. To give you an idea, I went through 6 different suspensions on my old VW before I got it right, but that 6th one was amazing.
So when I bought my WRX in June of 06, coming from a awesome handling VW and MINI Cooper S, I was left disappointed with the rolly-polly boat handling I had just fallen into. It understeered worse than any FWD I had ever owned, and body rolled like it was on air suspension.
So one of the first things I purchased was 22mm sway bars, endlinks, and "stout" mounts. After all with my old cars, that was the best starting point to dial out understeer, roll, and didn't require spending $1000 on a brand new suspension for a brand new car. So I put those on, chased down the horrific squeaks (thanks Big Sky ) and while they dialed out "some" of the roll and understeer, I had been left wondering if I had bought too little sway bar. Sure I fiddled with the adjustment of the bars, but it never made a drastic enough difference.
So then I did a lot of reading on the forums and found that throwing lowering springs at the problem didn't necessarily help either. There was such a thing on the WRX as going "too low" and messing up the suspension geometry. So I bought a set of STi take off springs and put those on. They helped a little, but still not where I wanted to be.
Then I thought, well maybe the front is washing wide because of a lack of mechanical grip. So when it came time to change tires, I threw on a set of wider grippier ones. They helped, but if anything it just increased the threshold before the symptoms would show again.
After that, I just lived with it......for 80k miles. I figured I'd either deal with it someday, or sell the damn thing. Well sell the damn thing didn't happen, the suspension was worn out, so a few months ago, I dove back into it. I read everything I could find, and in those 6 years since I had started this journey, an absolute ****-ton of information had been vomited upon the forums. And I am eternally grateful it did.
So I bought:
Whiteline Com C top hats front
Group N top hats rear
Rear camber bolts
And set out to finally sort this suspension out. After I got the D-specs adjusted to my liking, I determined a vast improvement had been made. Good, I spent a ton of money. You could chuck the car into a corner with very little understeer, and if you applied enough gas directly after turn in, you could induce some oversteer. Cool.
But being an over analytical Mech Engineer with a lean toward Pessimism most days, I noticed that the initial turn in and resistance to understeer was good, but as the cornering load increased the understeer went from 0 to quite a bit. After the understeer had started, applying more throttle only intensified the affects. So since I align my car at home (check link in sig ) I threw more camber at it. It helped but the symptoms were still there. Also I noticed that the steering was not quite where it had been previous to the new suspension. So obviously something was happening when the suspension was being dynamically loaded.
Now many people would have just quit there...trust me I thought about it. But I figured hell I'm this far, probably $3000 into suspension at this point all in, why not see what else is out there. So back to the internet I went. After some weeding out of things, I decided to try a Whiteline ALK and Whiteline RCAK. Afterall the ALK was billed as dialing out understeer and roll, while the RCAK was billed as fixing my steering back to where it was originally.
So I installed them both this weekend. Install was pretty easy (note: I have a lift, may be more difficult on the ground), took me 5 hours start to finish, taking my time, to install both kits, build a ball joint tool, and align the car.
WOW WHAT A DIFFERENCE.
To recap, my suspension now consists of this:
Whiteline Com C top hats front
Group N rear top hats
Rear camber bolts
Perrin 22mm Sways F+R
Perrin End links
Perrin Stout mounts
Whiteline ALK comfort
Rear subframe lock down bolts
225/45/17's on OZ Superleggeras
Group N motor mounts
Group N pitch stop mount
STi tranny mount
TIC crossmember bushings
All shifter bushings done
toe = 0
What a damn difference those two parts totaling $429 shipped to my door made. So much so, that I would wager a guess that had I left the STi springs, sourced stock replacement struts (like a KYB), and just done the ALK, RCAK, and sway bars, not only would I be $1500 more in pocket, the car would handle 95% as well, and I would be more than satisfied.
What a huge difference...Huge. The car feels 100% neutral all the way through the corner, I can apply power all the way through the corner, it tracks amazing, steers amazing, turns in amazing and rides fantastic.
So, that is my 7 year long suspension journey on my 2006 WRX. Hopefully this write up helps someone out. If you are on the fence about an ALK, get off it. Seriously it is one of the first things I would add to the car.