Part 2:
SUSPENSION Setups, theory, experiences
Proper maintenance, tires, and alignment apply to all of the following setups.
The Daily Driver
You spend your time going Point A to Point B, but want something a little stiffer and a little stickier without ruining the ride quality or annoying your female companion.
Swaybars: Look into the Cusco 22mm bars all around for a noticeable but very light upgrade. If you want a little more at higher speeds, look into the 24-26mm range for front and rear. I'd recommend the RaceComp Engineering bars set at 25.5mm (softest setting) or Cobb/Hotchkis bars (if they've fixed the fitment issues). I'd stay away from Whiteline unless you don't mind the grotesque rusting issues and walking bar.
Tip: Ditch the grease on the bushings and wrap teflon tape around the bar where the bushing sits. No more grease required.
Endlinks: You'll want these so the swaybars don't break your stock ones or flip and damage your rear control arms. Avoid spherical bushings, they will only break down with time and operate noisily. Kartboy makes a hard to beat endlink design that has proven to be ridiculously durable and easily serviceable should the need ever arrive (it won't).
Cut your bumpstops: Take out your stock struts, open them carefully and remove an inch from the top of the rubber/foam cushion. This will improve your bump travel, ensuring a nicer ride quality and keeping the tire to the pavement under severe bumps.
At this point, you have a nice, comfortable daily driver that will not float or lean too heavily in turns. Congrats.
The Sport Upgrade
Take the daily driver setup and add the following:
Rear subframe and dif bushings: tightens up the rear of the car, you will notice it in your right foot when exiting a turn. cheap and effective at reducing slop in the rear of the car.
X-Brace: For GD sedans only. Tightens up the rear of chassis and is almost a must-do mod as it helps make the rear of the car feel connected to the steering wheel. Note: a rear strut bar or V-brace won't be nearly as effective due to the geometry of whats being connected.
Fender Braces: For all cars built before 2007. Redirects front suspension force from the cabin back into the firewall and suspension where it belongs.
The Autocrosser
Camber plates: You want a plate that has a beefy bearing set that will withstand the pounding that it'll take over bumps in the road and on the course. This means that you're not going to want to run some half-ass plate made in Taiwan if you value not having to replace it every 6 months. Look at the Vorshlag plates...if the plate you want to get doesn't look as beefy, don't buy it...unless you like replacing car parts. Camber plates for up front to get your car the -3 camber it needs and some pillowball mounts out back since you will never find a need for more than -2 camber out back, which can be done with stock hardware and ride height.
Coilovers: Oh boy, you knew I was getting here eventually, didn't you?
First, lets start with something you need to keep in the back of your head when navigating these waters:
"Andrew's top 5 things to look for in a coilover
1. A solid US presence from the manufacturer. Can you have them rebuilt quickly and easily without sending them to China, Japan, Germany, Afghanistan, etc.?
2. Spring rates. If a manufacturer puts out mismatched spring rates....it's a good sign they don't know what they are doing. Seriously big red flags should go up if they do this.
3. Can you get someone on the phone to talk to you about the shock and how to adjust? How about good alignment settings? How about being able to do that on the weekend when you're at the track?
4. Damper travel. You can't soak up mid-corner bumps (or potholes) if you only have an inch of travel before hitting the bumpstops. Lots of coilovers are like this unfortunately. Separate ride height and preload adjustment is nice, but if you have hardly any travel to start with....sorry....you're gonna have some trouble.
5. Valving. The hardest to see and the hardest to evaluate. Shock dyno plots are helpful but can be difficult to understand and not always available. Can the vendor explain how the shock will feel and the reasoning behind the valving?
Remember....a kidney crunching ride is NOT always fast."
So what does this all mean for you? Here's a quick and dirty coilover lesson. If its from Taiwan, Japan, Korea, China or the Philipines...don't buy it. I will explain more later in the theory section of this write-up. If it's made by KW, Ohlins, Bilstein, AST, Penske, or Koni...buy it.
Anti-Lift Kit: Only if you want to run in SM class in SCCA, or if you just don't care about classing rules. This will help you gain caster. Caster is good because it influences your camber curve dynamically and keeps it negative longer.
Roll Center Adjuster Kit: If you lower your Subaru, buy this. It will fix what you screwed up by lowering the factory geometry.
Ride height setting: 14" from the center of the hub to the top of your fender-well in the front and 13.5" in the rear. Why? Because that's what has been recommended by Javid among others that race Subarus on track for their careers. The math bears it out as well for the car's cg and suspension geometry. If you see someone lowering more than this for looks, you are allowed to snicker because the car will handle and ride like ****.
The Tracker
Subframe brace: Reduces front end weight on a front end heavy car. Also stiffens up the chassis.
Lightweight battery: Reduces front end weight by 10-15 lbs. A track car wants this.
JDM front bumper beam: Reduces front end weight by 20-30 lbs. A track car wants this.
Strut Tower bar: Stiffens up the front end when high spring rates are chosen that can make the chassis mounting the weak link.
Group N bushings or Lateral Links and Trailing Arms: Get rid of the slop in the rear of the car once and for all.
Theory
Dave's Rules of Suspension
1). Stiff is not always fast.
2). JDM sucks.
3). Less is more.
Lowering Springs: Notice I never mentioned them? Good. That's because they're awfully overrated for something that accomplishes a lot more bad than good. Here are the Pros and the Cons.
First, the Pros:
-Lowers the car which lowers the cg
-Increases spring rate
Now, the Cons:
-Lowers the car too much 99% of the time
-Eats up precious bump travel, reducing ride quality and suspension compliance to zero.
-Does not increase the spring rate enough to really matter
-Reduces shock life substantially
-Doesn't always take corner weighting into consideration (Swift does..yay Swift)
-Have yet to show much of a decrease in lap times.
Coilovers: Asian coilovers are valved to have high rebound in the low speed and high speed area of the shock dyno. This is bad for ride quality and bump absorption. This means that the tire will leave the pavement over bumps on track. This is a loss of traction.
Asian coilovers also do not offer much strut travel, which when combined with the valving, mean a lot of areas on bumpy roads or tracks where the damper is not keeping the tire to the pavement.
Asian coilovers love dual-height adjustability. It means nothing for performance since there isn't enough strut travel to make use of it. Maybe some inboard spring clearance could be had, but that's not a sure thing.
Asian coilovers are expensive despite all of these downsides. For some reason, people run them under the pretense that they're decent. Not sure where that came from.
BC Racing, etc. coilovers. Cheap and effective for autocrossing. Not comfortable on the GD for the street and will overheat on the track. Camber plates rust out and the bearing will disintegrate after 6 months to a year. You get what you pay for, but if you are smart enough to avoid lowering springs but can't afford good coilovers, you buy these and accept the drawbacks rather than pay twice as much for Tein, Cusco, HKS, etc. and think its good because of the brand name and price while receiving similar product.
Bilstein PSS-9 coilovers. Good for street driving, but the adjuster is inaccurate and thus this system is ultimately limited. Still a lot more comfortable than JDM and worth the money.
KW V3, RCE T2, etc. The standard for a track coilover that retains some street comfort. The problem with the KW V3 platform is that the high speed portion of the shock valving cannot be changed with the adjusters, which means that no matter how much you dial in the system for 99% of the time, that 1% big bump in the road will make you go crazy.
AST 4000 and 5000 series. Excellent choice for comfort and track. Race valving can be manipulated to give an amazing setup at slightly less than premium pricing.
JRZ. If you want to win, you buy JRZ, period. I didn't mention this brand before, but we're not talking about racing on a budget here, we're talking about shutting up your entire car class and the exotic owners that hate your spoiler. Cha-ching.
Ohlins. The DFV has a reliable adjuster that can properly influence both low speed and high speed valving. The problem is that the valving out of the box could use some work. The solution is to call up one of the many Ohlins revalving centers in the U.S. to fix that. Then you're on another level from nearly everyone else with quality components to back it up.
Penske. File under JRZ/serious tracking. Will crap all over everybody else since it will be custom built to your application and cost big bucks.
Koni. And finally, everyone's favorite budget shock that can be revalved to compete with anything...the Koni. Match this up to ground control springs and perches and you'll be light-years ahead of most on a budget setup.
Experiences
Tokico, Cusco, Tein, KW, RCE, Whiteline, BC Racing, Megan, HKS, Greddy, Koni, AST, Ohlins, KYB, Bilstein, Vorshlag, Stance, Tanabe, Apex'i, Ground Control, and JIC to name a few.
Conclusion
At the end of each of these stages, your goals for the car should be satisfied. The decision for where you want to take the car is entirely up to you, but my advice is to start small and find what your limits are as a driver rather than as a consumer. You may find that having the tracker setup is too extreme for what you really use the car for, or you may find that the daily driver doesn't offer enough for your liking. that's ok...its just a lot cheaper to be in the daily driver and know that satisfaction is only a part or two away rather than $5,000 of wasted investment.
If you opt for the The Tracker, I can guarantee you that your Subaru will be as good as it gets. From that point on, it will come down to your driving ability and learning curve. Enjoy.
If you'd like to go further in-depth into suspension tuning, then this site is a great place to bookmark and read through:
http://farnorthracing.com/autocross_secrets5.html