Hopefully without spoiling the conclusion of this review, please let us make something crystal clear - the soul of this vehicle resides under the hood. Come on, it's a frickin' Corvette motor - in a SUV. How cool is that? Quite cool, in fact; at least to those of us with 20W50 motor oil running through our veins. The right answer is always "more power", and if it's not, then the correct question isn't being asked.
But 395 HP and 400 lb-ft of torque is useless unless it can be delivered to the pavement, and that's where a bit of sophistication on the behalf of GM's powertrain and chassis engineering teams come into play. Sure, some out there will roll their eyes at this claim, but we respectfully request that the reader put his or her preconceived notions on hold until the conclusion of this review. In the meantime, let's literally pull this thing into the Autoblog Garage and take a look underneath to explore the hardware that has been charged with maintaining the integrity of the Super Sport name.
We've expended quite a few electrons discussing the GenIV LS2 V8, so we'll keep things brief. Simply stated, this engine is compact, light, simple, and reliable. Any doubts about this engine should be answered by a quick glance at its dyno chart, where one should quickly draw the conclusion that it makes a boatload of power just about anywhere in the rev range. By 1000 RPM, it's making 300 lb-ft of torque, and never again drops below that number. Peak power occurs at 6000 RPM - who said anything about pushrod engines being "low-revving"? Want to get into a torque-vs.-horsepower argument? Forget it - this engine's ability to pull hard regardless of the tach needle position should lay waste to such useless banter.
Unfortunately, removing the plastic engine cover does little to appeal to our aesthetic sensibilities. Instead of the 4bbl carb and single-plane intakes of yore, we see a barrel-type manifold adapted from the lesser TrailBlazer's 5.3 L; ironically enough, the Corvette's manifold is said not to fit under the cowl of this truck. This supposedly is the main reason for the 5 HP loss incurred during the transplant into the TrailBlazer, but we doubt that the only time it'll be missed is during heavy bench-racing sessions. To be honest, our gut says that the mechanical fan is a more likely suspect for the lower rating, but its superior cooling abilities will be welcome during worst-case towing situations. Interestingly enough, the manifold lowers the torque peak by 400 RPM without affecting the location of the horsepower peak, so it's possible that it results in an ever-so-slight increase in the much-desired "area under the curve".
The lump is fed via an airbox that sits behind the passenger's-side headlamp, and a small duct is provided to feed cold air to the intake tract. Is it effective? That's debatable, but real-world considerations and OEM standards that prevent problems such as water and debris intrusion make it very difficult to implement a true cold-air intake. Regardless, we appreciate the attempt.
Let's now venture into the Autoblog Garage's pit, which is a scary place indeed (especially this time of the year, when slight flooding can be expected).
Up front, the same short-long-arm (SLA) system that is used on other TrailBlazers is retained. However, the vehicle is lowered, significantly stiffer springs are fitted, and a 37mm sway bar is affixed to the lower control arms via a pair of beefy aluminum links. Likely having the biggest impact, though, are the Bilstein dampers that are installed at all four corners of the vehicle. Never, ever, underestimate the impact that a good set of shock absorbers can have on a vehicle.
We also see here the fairly large 12.8" brakes and two-pot brake calipers, but the system looks a bit tiny relative to the 20" wheels.
Those big brakes are cooled via vents in the front fascia and a set of ducts that direct the air towards the caliper and rotor. Those of us that engage in backroad thrashing, autocrosses, and open-track days with heavy vehicles really appreciate such touches, and they go a long way towards establishing this vehicle's high-performance credentials.
As we've already mentioned, the TrailBlazer SS routes its power to each set of wheels via a single-range full-time transfer case. The magic is achieved via the use of a Torsen T-3 limited-slip differential, which uses a series of gears to smoothly bias drivetrain torque. In this case, 67% of the available torque is routed to the rear wheels, but that can be limited to 55% or increased to 75%, depending on available traction. Oversteer fans will find that enjoying their craft isn't totally ruled-out by this AWD system.
The twin downpipes and catalytic converters merge via a Y-pipe into a single exhaust system. Two mufflers - one located before the axle, and one located after - attempt to silence the powerplant. Let's just say that they wage a valiant fight, but are overwhelmed in the end. The exhaust system allows the escape of maybe the nastiest exhaust note we've heard from a Detroit product since the era of the muscle car. It's tame at idle but quickly draws attention as the throttle is opened, eventually getting loud enough at WOT to attract dirty looks from bystanders. Since we think that the baritone roar of a V8 one of the finest sounds that a motor vehicle can emit, we were left wishing only that every vehicle could sound this good.
Out back, we find a solid axle; in this case, the beefy 9.5" 14-bolt unit that's usually employed in 3/4-ton trucks. An Eaton Posi, loaded with the company's 400-lb preload spring pack, keeps the torque flowing to both wheels. A 24mm sway bar keeps roll under control. Fore-aft location is managed via a set of upper and lower trailing links (4 total), which is a system that has proven very effective at preventing axle hop and provides the ability to tune in anti-squat and anti-dive. Lateral location is a weakness of such a system, so a Panhard bar is employed to keep the axle where it should be during hard cornering.
Unfortunately, that Panhard bar does pinch the exhaust a bit. We'd expect the aftermarket to come up with a solution for this issue.
Apparently, it was deemed necessary to use an auto-leveling air system out back in order to combine the vehicle's impressive towing capability with its low ride height, and so air springs are used in lieu of the coils that are normally employed. Because of an air spring's rising-rate characteristic, they often can cause a harsh and bouncy ride, but this system is transparent with regards to ride quality or handling. Once again, we give credit to the Bilstein shocks. OK, admittedly, we also like the bit of eye candy that the bright-yellow tubes provide.
Think your job is tough? Trying being a rear brake that's caught between the traction control system and a vehicle with nearly 400 HP. A few runs up and down an icy gravel road to test the effectiveness of the AWD system left the rear brakes that lovely bluish-purple sheen that comes only through intense heat.
So, how well does all this hardware work? Stay tuned for Days 4 and 5 of our experience with the TrailBlazer SS, where we'll wrap things up with the impressions that we've formed after a week of thoroughly thrashing this vehicle in a variety of driving situations.
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