Chevrolet's 2002 TrailBlazer is drawing rave reviews for its 270-hp inline-six. Fortunately, for the five million or so previous-model S-series owners, there are options available that'll prevent them from feeling too old or too slow. Introducing Project Blazer--a tastefully styled and highly modified take on the '95-'01 Blazer/Jimmy/Bravada/Envoy. Call it a more refined and less compromising younger brother to the GMC Typhoon.
Outside, the biggest changes for this 1999 4x4 are obvious. The Stillen urethane front-bumper cover lends a much more aggressive yet cleaner complexion to the Blazer's nose. The chrome center strip was painted body-color red to keep things consistent (you'll also notice the gold Chevy emblem has been replaced by a black and red number from an SS-packaged pickup). On top, the fiberglass ram-air hood from Ctech Industries makes this Blazer unique and aids in cooler breathing for the engine (the Powerstack filter resides just inside the opening, creating a near ram-air setup).
On each side, the clunky black side mirrors have been replaced by Stillen XL Sports. These lower-profile units plug directly into the factory wiring harnesses, retaining the stock power controls. Around the Blazer, all chrome pieces, side moldings, and badges have been removed. The missing Chevrolet emblem on the rear tailgate has been swapped out for a small supercharged piece originally designated for the rump of a Buick Riviera. All paint and body work was performed by Passwater's Auto Specialists in Indianapolis.
Headlights have been upgraded with APC's Plasma Xenon Super White Bulbs that simulate HID output. If that's not enough, two pairs of APC 55-watt halogen driving lights are integrated into the Stillen front spoiler and wired up to the factory foglight switch. For those keeping score, there are no fewer than 10 separate bulbs turning day into night on the front of this beast, eight of which may be used simultaneously (not that we recommend that sort of thing). It's worth mentioning that in a foggy rainstorm at night, the low-slung amber units in the bumper guided the way easily and without a single flash from oncoming traffic.
A set of EGR urethane fender flares enhances the truck's stance and provides some much-needed muscle tone to the Blazer's notoriously tall and skinny physique. Filling up those bulging fenders is a set of 17-in. Gara Series 122 wheels from the Tire Rack, while the tepid, stock 235-75 all-season rollers have been swapped out for Bridgestone Dueler HP high-performance street-truck tires (265/60-17 front, 275/60-17 rear).
The Nitty Gritty
A pop of the sculpted hood reveals the secret to the 4.3L engine's power production - a Vortech supercharger blowing 10 lb of boost into the normally docile powerplant. The 50-state-legal blower is the new V2-SQ unit that's quieter and smoother than Vortech's previous models and is now standard across the product line. All by itself, Vortech claims a 43-percent increase in power--a nice gain, yes, but we wanted to go for a touchdown rather than settling for a field goal.
To that end, we also included a set of JBA's ceramic-coated headers and a Gibson cat-back exhaust system, ensuring the supercharged gases would exit quickly and easily, providing increased power at the same time. The most unusual piece of the puzzle comes from the enormous three-core air-to-air intercooler residing under the front bumper. This intercooler reduces intake temperatures significantly, allowing for more boost with less worry of piston-melting detonation. The final piece of the engine puzzle comes from custom reprogramming of the engine-control unit by Fastchip of Tulsa, Oklahoma (www.fastchip.com). Master technician Ed Wright's flash reprogramming adds response from as low as 400 rpm. His handiwork also recalibrates transmission shift points and firmness for more spirited driving. Additionally employing a 160 thermostat, Fastchip tweaks the engine-cooling fan for increased performance. The Fastchip ECU program goes several steps further than the popular Hypertech plug-in models, but requires sending the ECU to them to work its magic. It was well worth the one-day turnaround as our peppy blown motor ran smack into the rev limiter in first gear prior to the Fastchip reprogram bringing things back under control. All told, the engine tweaks nearly doubled the horsepower, making the grand total to a Corvette-like 337. It's worth noting that, at the start of our project, Chevy dyno results netted only 160 at the flywheel. Torque numbers jumped as well, from 205 to 308, which, by the way, is more than you'd get from an Acura NSX (224) or a Porsche 911 (258).
Too Hot To Handle
It seems that many highly tuned SUVs have a difficult time finding a balance between increased handling and quality ride characteristics. Often, getting 4000-lb behemoths to go left and right in a sporting fashion requires eliminating their built-in-utility features as well as severely compromising day-to-day ride. Given that this Blazer is a 4x4 and faces four full seasons of weather, it was paramount not to drop it 6.0 in. and install 40-series rubber. Complementing the aforementioned tire upgrade is a set of Edelbrock Performer IAS shock absorbers. Edelbrock calls the IAS shocks the first in existence that drastically reduce chassis roll without compromising ride quality. This best-of-both-worlds setup fits right with Project Blazer's goal to increase handling while retaining the stock ride height.
Also, a thicker Hellwig rear anti-roll bar aids in reducing body roll. A complete set of Energy Suspension polyurethane bushings are included in the mix, as well. Energy Suspension claims a firmer ride, with less wheel hop under hard acceleration, along with three times the longevity of the stock rubber bushings. A set of Stillen's cross-drilled sport rotors and metal-matrix brake pads at all four corners ensures the Blazer stops as easily as it starts.
Inside, the classy leather interior of this LT-level Blazer remains intact, unless you count the addition of a mostly stealth yet powerful audio system with components from Premiere, Boston Acoustics, and Alpine. A custom subwoofer enclosure and amp rack have been integrated into the rear of the Blazer. This extremely subtle yet terrific sounding system was designed and installed by Audio Electronics of Indianapolis. The dash is also dressed by a Speed Glo white-face gauge kit from APC. This snazzy piece reads white during the day, but changes to a luminescent glow for night driving and draws praise from everyone who sees it. A pair of AutoMeter white-face gauges are mounted on the A-pillar to provide the all important boost and fuel-pressure readings.
On the Road
A twist of the key reveals a much more aggressive snarl from the 4.3L V-6. The Gibson exhaust works as advertised, keeping the noise out of the cockpit, resulting in a deep, smooth growl from the subtle polished tailpipe. The second thing you notice is this Blazer zips that fancy tach and speedo along as if there's a V-8 underhood--and a strong one at that. Acceleration is more Mustang GT than SUV with 5.9-sec dashes to 60 mph. The added power makes passing and moving through traffic a snap.
The handling of this Blazer is really no harsher than stock. Granted, it won't corner as well as a slammed, fender-rubbing sleekster, but it holds the road much better, with far less body roll, than stock. Plus, it'll still go over the river and through the woods without scraping its nose on bottle caps and discarded pennies.
The braking also has improved significantly as the fade-resistant drilled rotors bring all that weight to a halt with much less drama. In all, this Blazer more than makes up for the lack of a V-8 option enjoyed by the competitors in Explorers, Cherokees, Durangos, etc. Additionally, most of these parts work even better on the S-10 and Sonoma pickups, given their weight advantage compared to the SUVs. Although this took quite a bit of time and effort, we're enjoying the result. We even had an '02 TrailBlazer driver snicker at us from behind the wheel of his meaty new inline-six. We snickered back and left him at the stoplight in our blown 4.3.
4.3L V-6 Expertise
One of the gurus of the Vortec 4300 is Bill Mach of Mach Performance outside Detroit. Having developed performance applications for a variety of automotive and marine engines, Bill was nearly overwhelmed with interest in the 4.3L block once word got out that he had a full line of products for it.
TRUCK TREND: How strong is the 4.3 motor?
BILL MACH: We've found it to be very stout. Remember, this is basically the 5.7L V-8 with two cylinders lopped off. Its cast-iron block is strong enough to handle turbo or supercharging up to 350 hp without modifying internal components.
TT: What do you have available for the 4.3 performance-wise?
BILL MACH: We have a full line of engine components--cams, pistons, rods, rocker arms, etc. We also do cylinder boring, valve jobs, computer-flash reprogramming, and a great deal of custom work. We are the designer and exclusive dealer for the ATI Procharger intercooled supercharger system for the 4.3 engine, and we recently introduced an intercooled turbocharger package as well as complete nitrous kits.
TT: Is this equipment applicable to all the models across the GM line with the 4.3 motor?
BILL MACH: Yes. Although there are some variables from year to year, we can offer just about anything a customer would want, from mild to wild. This applies to '96-'02 S-10 and Sonoma pickups as well as the Blazer, Jimmy, Bravada, and Envoy variations (two- or four-door and two- or four-wheel drive). We can even build you a 400-hp Astro van.