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Suspension Science

Before going any further, please keep in mind that what the chassis engineer ‘likes’ and what the driver ‘likes’ can be 180° out of phase with each other. Unlike other vehicle systems, chassis tuning is as much ‘art’ as it is ‘science’. The only underlying truism is: if it gets you to the checkered flag first, it’s right! With that in mind…

We have found that the Saturn suspension should be attacked as a system, and that randomly replacing individual components without some forward thought can actually have a detrimental effect on chassis dynamics. What we will roll out below are a series of upgrade ‘stages’, but remember that the first step toward the improved chassis of any Saturn involves swapping in some real wheels and tires!

The first stage involves ‘firming things up’. A strut tower brace, although illegal in all but CSP, will make an immediate difference. Keeping the stock springs in place but replacing the struts with KYB units will raise rebound damping rates without keeping the springs from doing their job. Adding a larger rear anti-sway bar (16.5mm diameter) from SPS will dial out some of the factory understeer, but keep in mind that if you choose to add a front bar as well, you will negate part of this effect. These changes will make for a fun to drive street car with minimal impacts to ride comfort. For the street, alignment should be kept reasonable, with no more than -1.25° camber front and rear, zero front toe, and a hair of toe-in in the rear.

The next stage is to upgrade to a high-performance street set-up. H&R sport lowering springs, when combined with Carrera street struts, make for a firm, but tolerable, ride. With the installation of the H&R springs, an SPS 3-way adjustable 16.5mm rear anti-sway bar can now be used to make fine chassis adjustments (note: we recommend leaving the front bar stock in this configuration). Adding 10mm to the track width with spacers makes for wheel clearance and helps to reduce body roll a small amount. Alignment can now be turned up a notch, but any more than -2.0° camber front and rear will wear out street tires in a hurry. Front toe out should be set to the driver’s preference, and rear toe should depend on what type of racing you are setting up for – zero toe for road racing, and some toe out for the autocrossers. Be aware that at this point, you are close to crossing the line between daily driver and weekend warrior. At scR motorsports, we utilized these same components in our 1998 SSC ‘trunk kit’, and found the handling balance to be ideal for road racing.

Teaser line: for 1999, we have re-engineered the SSC ‘trunk kit’ with the assistance of H&R, SPS, and several others. At the time of this writing, the package has not been voted on by the SCCA Comp Board, but by the time you read this, something should be official – one way or the other. Be sure to visit our website at www.teamscR.com for the latest on the 1999 allowances.

For the ITA curious, there are coil-over kits available to transform your suspension package from high-performance street to full-race. At this stage, springs are best determined by experimentation and driver preference, but rates are available to suit any taste. Camber plates, minor geometry changes, and better bushings are all fair game, but with so many schools of thought on how to set up a front-wheel drive race car, we won’t go there. Experiment and find what works best for you.

What Doesn’t Work? What Are The Weak Links?

Our self-generated list of broken parts, lessons learned, and dollars wasted:

  • Suspension bushings are a great idea if you can replace them all the way around. If you replace only some of them, you might get unwanted understeering or oversteering of the rear axle.
  • Don’t replace the front anti-sway bar unless you are prepared to go with a huge rear bar. Use springs to control front roll angles instead.
  • If you lower the car more than 30mm, be prepared to replace front axles on a regular basis – the resulting axle angles will eat the CV joints.
  • If you do end up road racing, buy a whole bunch of rear wheel bearings. Over the course of 9 races, we went through 5 pair. Front bearings are a little more robust – 1 set should last 6 races or so.
  • Spend real money for quality brake fluid and brake pads. Saturn racers will curse the day they shortcut this critical area.
  • Don’t spend money for any Saturn engine components which magically add 15 horsepower. They don’t exist, and unless you only run on the street, they’re probably illegal anyway.


Putting It All Together

Now that you have been saturated with Saturnalia, you are probably sitting back and saying to yourself, "Self, this sounds like any other GRM article". Well, you are right…the preparation and maintenance of the Saturn SC2 is as simple as that for a GTI, Miata, Civic, or Neon. Contrary to popular belief, the Saturn does not require special care or feeding, and in most cases is actually easier to maintain than other popular marquees.

To sum it all up, there is no silver bullet which will enable your Saturn to heroically catapult to the top of the pack, but when you combine the light weight, agile suspension, flexible powertrain, and growing aftermarket support for the Saturn SC2, you might just realize that Saturn provides one of the most competitive packages to campaign, no matter what your end goals. Get ready to run "rings" around your competition!

SIDEBAR 1 - The Saturn Decoder Ring, Part I


All of the vehicles in the current Saturn lineup are identified by specific model names which, at first, seem like a random string of numbers and letters – SC2, SL1, etc. Here is the super-secret decoder ring to figure out just what each model name means (I could get fired for giving this away).

  • The first character in the model name will always be an ‘S’. Maybe it stands for ‘Saturn’, but I don’t know for sure.
  • The second character in the model name identifies the body style: ‘C’ for coupe, ‘W’ for wagon, and ‘L’ for sedan. Hence, you can choose from the Saturn SC, SW, and SS SL. Freudian slip – Saturn SS. Ha! What was I thinking?
  • The third character in the model name essentially indicates the engine and suspension configuration: ‘1’ for the 8 valve single cam engine / base suspension and ‘2’ for the 16 valve twin cam engine / performance suspension. See the next side bar to decipher these cryptic phrases.


For example, the Saturn SC2 is a Saturn coupe with the performance suspension and twin cam engine. An SW1 is a Saturn wagon with the base suspension and single cam engine. Simple once you have broken the code, right? What it really boils down to is that, under the body panels, Saturn only produces two cars – the 1-series and the 2-series. The rest is just bodywork – from the underside an SC2 is the same as an SL2, an SL1 is the same as an SW1, and so forth.

Hopefully my desk will not be cleared out when I get to work Monday morning!

SIDEBAR 2 - The Saturn Decoder Ring, Part II


Most 1991-1997 Saturns share common engines, transmissions, braking systems, and suspension system components. In order to quickly spell out what differences do exist between the 1-series and 2-series cars, we have compiled this quick-reference guide (as opposed to having quickly compiled this reference guide).

 1-Series Saturns
2-Series Saturns
Engine
  
Displacement1.9 l, 8 valve SOHC I4
1.9 l, 16 valve DOHC I4
MaterialAluminum block and head
Same
Compression Ratio (:1)9.3
9.5
Power100 hp @ 5000 rpm
124 hp @ 5600 rpm
Torque114 ft-lb. @ 2400 rpm
122 ft-lb. @ 4800 rpm
Redline5600 rpm
6750 rpm
Manual Transmission  
1st–5th Gear Ratios (:1)3.25, 1.81, 1.17, 0.81, 0.61
3.25, 2.06, 1.42, 1.03, 0.73
Final Drive Ratio (:1)
4.06, open differentialSame
Brakes
  
Front Brakes
250mm vented disc ABS optional)

Same

Rear Brakes
200mm drum
Same, but 251mm disc with ABS option

Chassis / Suspension
  
Wheelbase
102.4" (99.2" for '91-'96 SC’s)
Same
Front Track
56.8"
Same
Rear Track
56.0"
Same
Front Suspension
Independent strut with lateral link and integral anti-sway bar
Same, but with larger front 28.6mm anti-sway bar

Rear Suspension
Independent tri-link with strut module

Same, but adds rear 15mm anti-sway bar
Steering Ratio (:1) 18.3, power assist16.3, variable effort power assist
Wheels 14" x 5"
15" x 6"

(Disclaimer: the figures stated above are specifically for the 1997 model year. Saturn has progressively tweaked its vehicles since 1991, but the figures for all 1991-1997 Saturns are pretty darn similar to those listed above.)