Auto Test Drives
STS-V Helps Cadillac Define its New Supercharged Performance Roots
By Andrew Gardner; photos by the author & W.L.T.
Jul 25, 2006, 22:17 PST

*Note: Check out the STS-v in action by viewing the video at the end of the article!



The STS-V rocks, and its wheels roll fast. It combines a ferocious powertrain with cuddly luxury, all encased in the new Cadillac look.


The visual cues which set this V-ified Caddy apart from its normal STS alter-ego are few and subtle: larger air inlets in the front fascia – for engine and brake cooling, as well as a splitter integrated in the lower-hanging fascia to counteract the lift generated by the larger grille - plus the V badges and “SUPERCHARGED” lettering glued onto the doors. Larger rocker panels tie the lower-hanging front and rear fascias together. Big brembo brakes inside the sport 18” front and 19” rear wheels also set this STS-V apart, but these are all subtle enough to not raise the eye of every passer-by; and depending on your point of perspective, you wouldn’t guess this was supercharged. It’s a good sleeper model.


Inside, the right interior for the STS is found. Where there was an overabundance of plastics on the STS, though perhaps not per its price point, the STS-V features leathers over a greater variety of surfaces – now including the dash, the door uppers, and the console, rather than just the seats and steering wheel. Olive Ash Burl wood anhances elegance, and “kinetic-finish” aluminum provides a touch of dazzle. The look is fantastic at first glance, especially with the abundance of dark charcoal color gracing the smooth leather. The look and feel of the texture, the enhanced softness, and the smell all contribute to an experience more suited to mid-level luxury. And the kicker is, the leather supplier is the same one which Maybach uses. Sweet.




But then you look a little harder and you start to see several fitment issues. Where the top of the door windowsill meets the dash is usually not quite right in most cars 50- and $60k and under, but when you start climbing ever closer to the $80,000 sticker range, you expect this to be right, and Cadillac misses here. The base of the radio stack where it meets the console in front of the shifter fits ok, but the seams of the leather stitching between the various pieces of each don’t meet up. The stitching elsewhere has alignment issues. This is a huge step up from the STS in terms of quality, but it doesn’t hit the mark for its price tag.


The other interior annoyance was with the nav system. It had been tweaked since we drove the STS several months earlier, and it was a bit more difficult to use, perhaps largely due to lack of familiarity and the fact that we expected different things to happen. The key issue was with the route calculation which we couldn’t figure out quickly enough. It turned out to be a small red button at the bottom of the map screen, sitting low and unlabeled.


But again we return to the balance of things, the power and the driving experience to be had for at least seventy four thousand copies of those George Washington-emblazoned green backs. There is supercharged Northstar V8 power rumbling beneath that edgy hood, and revised suspension under your seat and feet to improve direction-changing performance.




The powertrain is more than simply impressive. The Northstar V8 in the STS already throbs with 330 horsepower, and a patented Eaton blower co-developed with GM boosts that number into rare 469hp (at 6400 rpm) territory. Peak 439 lb-ft of torque, reached at 3800 revs, launch this mid-size (116-inch wheelbase), mid-weight (4300 pounds) saloon off the line with glee, sending you noticeably firmly back into your seat and causing you to strain your neck a bit to keep it up off the headrest. There is little pause to get into the full meat of the power with a quick transition from brake to throttle, and loading up the torque converter will provide an instant snapping off the line. The torque does not seem to mind the 3.23:1 rear gear; Germany would certainly have much more to worry about if a shorter gear were fitted. Variable timing of the dual cam-driven valves ensures proper breathing of the engine at all rotational speeds. The acceleration is unabatedly strong through the rpm range, the roots style supercharger shoving air down the intake ports with a delightful shriek and wail (more on this supercharged powertrain will be covered in a later article). By about 4500 rpm at wide open throttle you will approach 11 pounds per square inch of boost, and at max you will see over 12 pounds of boost – that is some very high manifold pressure for a non-turbo forced induction production car. And at this point, the Northstar V8’s throaty roar has a tough time competing with the supercharger whine for your aural attention. Acceleration is sure to bring a grin to your face, whether through your shear joy or just through your shear inability to keep your cheeks forced forward under such a magnitude of positive change in velocity (slight exaggeration).




Between the crank and sturdy driveshaft sits the 6L80, GM’s new 6-speed automatic with 32-bit electronic control, in its first application. The transmission is great, but could use some enhancement in smoothness. It can be made to do some rough transitions in situations other than wide-open throttle acceleration. Mostly, it performed well in providing quick but unjarring shifts under constant but heavy throttle pressure and very smooth shifts under light acceleration. It is also commendable in the fact that it handles such great torque with such aplomb; the 6L80 provided shifts much smoother than we have seen from the 4-speed transmission in most of GM’s products.


Other drivetrain unsmoothness came at times when transitioning to full supercharger bypass into boost operation. When you apply little or no throttle, air is bypassed around the supercharger rotors (very common modern practice)  for more efficient operation; when you get back on it, or when you quickly lift off from full throttle acceleration, the transition involving the bypass butterfly valve is rough, though not bone-shattering. If you can put a bit of effort into not so severely lifting off the throttle, the powertrain will reward you with the level of smoothness it is expected to offer.


The steering is light but not numb, tuned certainly for a luxurious feel while maintaining service as a gauge for how your front tires are behaving. A tall 17.2:1 ratio makes it indirect and more grand touring than sport in operation. A short-long arm front suspension with coils over monotube shocks and a multi-link rear with coil springs and load-leveling Nivomat shocks provide a nicely firmed but still comfortable and smooth ride. For all intents and purposes, the ride is as comfortable as an STS over rough roads, yet provides enhanced cornering capabilities. The resultant eagerness of the STS-V to tackle backroads is less than ferocious, but admirable and thoroughly enjoyable. This is no German ultra-high performance sedan, though it is notably nimbler than a base-level Bavarian midsize. A large 36mm diameter front sway bar, coupled with a 24mm rear, combats body roll. The fairly aggressive dampers squash down transition time to quicken turn-in, while sticky Pirelli rubbers (255/45 R18 front and 275/40 R19 rear) provide great grip.





The STS-V chassis is stable but not quite a rock, being set up to have some fun through steering and throttle inputs to effect mid-corner attitude adjustments. Unfortunately StabiliTrak kills your experimentation with chassis behavior as the moment you start to really scrub in the front tires, brake application and reduced fuel injection slow this fighter down. Thus, in full production spec, this vehicle is rock solid, being unperturbable at least within the sane maneuvers you would perform in having a nice performance drive through the esses. Launching the vehicle is also handicapped through the traction control whether it’s on or “off.” This electronic tuning speaks to Cadillac’s intended audience, as they expect a more affluent and mature driver than those seeking a CTS-V. This is disappointing for those more energetically enthusiastic drivers among us, but it is not totally fair to criticize given the competitors’ willingness to completely limit the slip angles drivers may encounter under dry conditions; they do have wet conditions to worry about, as well (and the STS-V is a lot more fun in the rain).


Within the electronic limitations, however, we do find the vehicle reasonably well balanced despite a V8 and supercharger mounted far up front. The turn-in and grip and stability make it a fun car to maneuver at heightened speeds through sweeping bends and right-left-right transitions. This makes an excellent grand touring vehicle for any day and any paved road.


And when you are ready for it all to come to an end, those 14 inch-plus diameter rotors with dual piston calipers front and rear, courtesy Brembo, bring this 4300 pound luxury rocket to a stop with much enthusiasm, thanks in part to Pirelli grip.


The STS-V is fantastic but notably soft. It is a proper and mostly well-executed two steps up in performance and luxury from the STS, but the interior fitment first and foremost needs to be addressed. A plea for more flexibility with the StabiliTrak in dry weather may be made, but the handling is good and the overall driving experience is both fun and rewarding, as well as comfortable. The cost of this vehicle is a darn sight less expensive than an M5 or E55 AMG, and what you get inside and out is reflective of this price difference. So, to be fair, this car hits a price point – but it is more than just built to a price. It is a powerful high performance grand touring vehicle just by itself. 





















See the STS-v in action by clicking the following links:

The STS-v motors uphill with ease (click here)

A quietly cruising STS-v (click here)

An STS-v cruises downhill again (click here)

The STS-v flexes its supercharged muscle with a quick takeoff (click here)



© Copyright 2001 by