Project Hypermiler: Handling Upgrades

Hypermiler's suspension definitely needed a refresh.  After 170,000 miles, the already pitiful stock bushings were showing evidence of imminent failure, and the boots were ripped on most of the joints.

The stock rear control arm bushing was tired of its hard life and had begun to crack.  Note the large air gaps in the bushing to increase compliance.  This bushing allowed as much as 1/2" of deflection with a small pry-bar.

Before delving into any project that is VW, make sure to order all one-time use torque to yield (TTY) bolts ahead of time.  In addtion, since an alignment would be needed after install, and the control arms needed removing to install some of the parts, new ball joints, tie-rod ends, and strut/shock upper mounts were ordered to give the shiny new upgrade bits a fresh start.  As usual, frustration springs eternal with the expensive array of hardware that needed replacing, and $80 was spent on replacing TTY bolts alone.  Make sure everything is assembled correctly the first time, as a mistake likely means needing to buy another TTY bolt.  This is generally compounded by the fact that most local VW dealers don't have sufficient stock on hand.

For this update, OEM parts were chosen for everything with the exception of Moog tie rod ends for their zerk fittings.  While zerk fittings would be useful on the balljoints as well, previous experience has shown that these fittings are susceptible to damage, ruining the balljoint.

OEM replacement parts were chosen for everything except the tie rod ends.

Moog tie rod ends were chosen for their zerk fittings to ensure the joint never goes dry.

The centerpiece for our suspension upgrades came from Suspension Techniques (ST) in the form of their Speedtech Coilover system.  Made by KW, these coilovers are virtually identical to a KW V1 setup with the exception of the materials used to construct them (the ST coilovers are galvanized steel instead of INOX), and feature all of the things that make the V1 setup work well: tender springs up front, progressive rate rear springs, non-metallic spring perches, and pressurized dampers with KW-tuned valving.  The best part is the ST coilovers come at a very reasonable price comparable to many damper and spring combinations, but allows the driver to choose a ride height between nearly stock height and 2.5" below stock height.  Most spring and damper combinations available featured relatively soft spring rates and lower the car too much, resulting in poor geometry and an overly familiar relationship between the driver and the car's bumpstops. 

When most everyone thinks of coilover setups and street cars, they think of a gritty ride, with clunks, rattles and squeaks from the spring perches resulting in huge amounts of APM, especially in parking lots where road noise doesn't drown these sounds out.  Luckily, ST sought to eliminate these common coilover problems  by utilizing the stock upper mounts, tender springs and progressive rate springs (front and rear, respectively) that maintain preload even when the wheel is completely unloaded, and non-metallic spring perches on the struts up front.   Non-metallic perches are not necessary for the rear end of the car because the spring does not turn like it does up front.
 

ST Speedtech coilovers are made by KW, and are almost identical to their V1 setup.  The ST coilovers feature galvanized steel bodies instead of INOX stainless steel.