Project GD Subaru STI Part Two- Performance Suspension, Wheels and Tires


Our fitment fills the wheel wells nicely.  We set our front camber at negative 2.5 degrees with zero toe.  Caster was 5.5 degrees positive.  We set our rear camber at 1.5 degrees negative with 1/8″ toe in.  This setup is a good compromise between track grip and everyday driving wear.
The Advan TCIII is a lightweight 19 lb wheel using roll forged technology.  First the basic wheel shape is high pressure die cast in an inert gas atmosphere to reduce corrosion of the highly reactive molten aluminum.  This gives a denser stronger structure with better grain than your typical gravity cast wheel.  After casting the wheel is then heated and rolled under high pressure to form the rim section into final shape.  This imparts the grain alignment and refinement of a forging and a strong, thin and lightweight  rim section like a super expensive fully forged wheel.  Since the rim on the outer edges of the wheel has the highest rotational inertia, this gives most of the benefits of having a completely forged wheel at a much lower price!
Although the Falken RT615K has the reputation of being a specialized drifting tire, it is a formidable tire for excellent grip with streetability. We were surprised by the amount of grip it had and its predictability at the limit.  We have measured phenomenal G loads on Dai Yoshihara’s drift car and the tires performed likewise on our STI.  Using our PLX devices Kiwi bluetooth adaptor and Palmer Dash Command software on a Galaxy Nexus droid phone, we recorded steady state lateral forces of over 1.2g’s!  The RT615K is not just a drift tire!  I think that our STI is currently the MotoIQ Project car handling champion.  With our plans it is only going to get better.

With our suspension wheels and tires in place, we have transformed our Subaru.  When we first got it, we were somewhat disappointed because its performance seemed like a distant second to the Evo’s in our project garage.  With some tuning help with first rate parts and some bigger tires, we have literally transformed our car.

Our Subaru now exhibits fast turn in with little understeer.  On hard cornering it is very neutral with a slight easily controllable amount of oversteer.  The car has lots of grip, more than our R35 GT-R that is currently awaiting project car massaging.

We think a lot of the Subies goodness comes from the low front CG of the boxer engine.  We previously were much in love with our Evo’s handling but with some help, we slightly prefer the Subaru’s!

After having more time on some of the really rough and poorly maintained roads in LA, you might want to run Whiteline’s softer bushings if your roads are really choppy as NVH was affected over really bad and choppy asphalt.  We mostly drive in Orange County where the roads are much better, in that case the ride difference between the hard and softer bushings was not really noticeable.

We slightly softened our KW Clubsports from their default in the middle settings for compression and rebound, reducing compression and rebound in the rear two clicks and reducing rebound only in the front by one click.  Unlike cheap coilovers, you can really feel the difference of one click on KW’s.  This greatly improved our ride comfort without sacrificing handling.  There is still a ton of adjustment either way.  Once adjusted the ride is better than the stock STI dampers!

Stay tuned, coming soon will be some engine help from our friends at Greddy and Cobb with a look at some really trick stuff coming from KW.  We will also work to add more camber adjustment in our front end and to add more positive caster.  This should really refine our STI and move it even higher on our fun to drive scale!


Read More about Project STI here!


KW Suspension

Mackin Industries Advan Wheels

Falken Tires

West End Alignment



PLX Devices – Kiwi Bluetooth

Palmer DashCommand


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