It's a question that's baffled the Western world for centuries. How the heck do you get "Bob" from "Robert," and which genius decided that "Bill" is a good way of shortening up "William?" Like most one-syllable names, "Brent" doesn't lend itself easily to an alternate handle, and it happens to sound pretty cool as it is. Nonetheless, in the case of Brent Jarvis, we'd like to throw an odd nickname of our own into the mix. Based on the way the man can set up a car, you might as well call him "Chad," as in Chad Knaus. You know, the guy who's arguably the best crew chief of all time, the one that's helped propel Jimmie Johnson to four-straight championships in NASCAR's premiere series? Like a Cup car, every nut and bolt in Brent's '68 Chevelle has been painstakingly scrutinized and optimized for on-track performance. And boy, is this sucker dialed in.
For instance, to haul the 2-ton sled down before entering a complex of chicanes, it packs six-piston Wilwood clamps at each corner, and a network of custom air ducts that keep the rotors cool. Twin fuel pumps virtually eliminate the potential for pressure failure, and a custom air-bleed system in the fuel lines protects against vapor lock. In the engine bay, dual remote oil separators prevent oil from spitting out of the breathers during high-g maneuvering. Furthermore, all the suspension geometry, spring rates, and shock valving have been vigorously tuned at the track. Brent can even increase or decrease sway bar stiffness in 75 lb-ft increments depending on race conditions. Not only does this Chevelle pull over 1 g in lateral acceleration, it runs the quarter-mile in 10.39 seconds at 137 mph on drag radials through a five-speed stick, courtesy of a nitrous-sucking 565ci big-block that throws down 804 rear-wheel horsepower. Oh yeah, the Chevelle just happens to be an original SS396 four-speed car, and is used as a daily driver.
If the name Brent Jarvis sounds familiar, it's because we've been tapping into the expertise and manpower of his shop-Performance Restorations in Mundelein, Illinois-during the build of our '65 Old Cutlass project car. A drag racer at heart, Brent owns a 7-second Pro Street '59 Corvette that's now been retired from active NMCA competition, and has had an NHRA pro license (good to 6.50s!) for the last 20 years. Straight-line proclivities notwithstanding, Brent has always appreciated cars that handle well. "Driving a car with 4-inch-wide front tires on the street isn't any fun at all, so I've always built my cars to handle well. The problem was that there just weren't any good suspension parts you could put on muscle cars back in the early '70s," he says. "My first car was a '65 Chevelle, and I figured out early on that you can shim the control arms for more caster, swap in Camaro spindles for more camber, and install urethane bushings and sway bars out of a big-block car to beef up the handling. When the Pro Touring scene started becoming popular, suspension parts were much easier to get and made your car look cool, but you couldn't really tell how well they worked without taking your car on a road course. After my first lap around a road course, I was hooked and used each outing as an opportunity to improve my car's setup."
While moving up the ranks in NASA, Brent earned a pro competition racing license in Super Unlimited Touring, the organization's fastest class. Over the years, he has owned and raced 13 different Chevelles. When a buddy who was hard-pressed for cash put his original SS396 four-speed car up for sale, he couldn't pass up the opportunity. "I've always liked this car because it's a real SS, and has unique factory options like the hoodscoops and stripes, so I had to buy it. GM never officially built an SS427 Chevelle, since the 427 was only available as a COPO or a dealer-installed option, so I thought it would be fun to build a tribute to a car that never really existed," he explains. Although he aspired to build a car that could do everything well, he didn't want to emulate the look of the typical Pro Touring street machine. "My goal was to build something that retained the essence of a '60s muscle car while performing well in every arena. I didn't want any modern high-tech gadgets, gizmos, gauges, racing seats, billet wheels, or custom exterior mods. I'm not a fan of bling."
A body man by trade, Brent felt it was worth it to pay a premium to start with a nice car up front. The Chevelle's body was in outstanding shape with no rust damage at all, but the vinyl top had to go. After welding up all the molding holes left behind from peeling off the top, the Chevelle was sprayed in period-correct Bright Blue metallic paint, and the stock emblems were replaced with "SS427" badges off of a '68 Impala. As with the body, not much had to be tweaked underhood, as the car already had a potent 565ci big-block. The combination uses a Dart Big M block, an Eagle crank and rods, and JE 10.2:1 pistons. Up top, a Pro Systems 1,000-cfm 4150 carb feeds an Edelbrock Air-Gap intake manifold, and massive CNC-ported Dart 335cc heads. "The car's former owner was a drag racer, so the motor was already pretty potent," Brent says. "The cam was a bit much for a street car, so I replaced it with an Erson 238/246-at-.050 hydraulic roller. Even with a smaller cam, the motor still made 601 rear-wheel horsepower on the chassis dyno. That number jumps to 804 hp on nitrous. The motor fires right up in the cold, and is so docile at idle that you'd never know that it makes so much power. Matched with the Tremec five-speed, it really drives great on the street and at the track."
With the motor and body sorted out, Brent went to work on the suspension. Armed with the expertise of having road raced A-bodies for over 10 years, the chassis tweaks were anything but typical. Brent selected a set of Global West control arms out back for their rugged construction and spherical joints, and set the pinion angle at negative 3 degrees for maximum forward bite. Likewise, the Hotchkis rear sway bar has been modified with custom Heim-jointed endlinks, and now attaches to the frame instead of the lower control arms. Brent says this arrangement reduces freeplay and increases the bar's effective stiffness. To prevent the rearend from unloading too much under hard cornering, Brent attached custom travel limiters made from 1/4-inch steel cable between the rearend and the frame. QA1 coilovers control body motions, and since the stock shock mounts were never designed to handle heavy spring loads, they have been reinforced with .100-inch chrome-moly steel plates and gussets.
Up front is a combination of control arms from Global West and SBC. The Global West lower arms are built like a tank, and the SBC upper arms feature a shimless design that uses steel bushings to eliminate flex. Instead of installing drop spindles, which can adversely affect steering geometry, Brent opted for a more creative solution. "It's amazing the kind of stuff you can find by just flipping through a NASCAR parts catalog. I installed a set of ball joints that are 1.5 inches longer than stock," he explains. "This raises the upper control arm at the ball joint area, which improves camber gain. Since they were designed for '80s A-body circle track cars, the ball joints are a direct replacement and are very cheap." Speaking of steering geometry, Brent installed spacers between the tie rods and steering knuckle until all vestiges of bumpsteer were eradicated. Moreover, a DSE splined sway bar helps manage weight transfer, but Brent took the design one step further by drilling four additional holes in the endlinks spaced 3/4 inches apart. This allows fine-tuning preload in 75 lb-ft increments. As with the rear, the front end uses QA1 coilovers, whose upper mounting brackets have also been reinforced with steel plates.
To any observer, the thoroughness of battle-tested engineering being infused into every nut, bolt, weld, and Heim joint in Brent's Chevelle is beyond brilliant, and defines the essence of this finely tuned machine. It's a final product that can only be achieved through a graceful coalescence of track time, deft fabrication abilities, and an intimate understanding of chassis dynamics. "Racing is the best way to sort out your car. Pounding on your car at the track and breaking parts makes you build better parts, which forces you to build cars that really work out of necessity," he says. Although we're not any closer to solving the mysterious origins of "Bob" and "Bill," at least the Chad-for-Brent nickname actually makes sense.
'68 Chevy Chevelle
Port Barrington, IL
Type: Chevy 565 big-block
Block: Dart Big M standard deck, bored to 4.600 inches
Oiling: Melling oil pump, Canton pan
Rotating assembly: Eagle 4.250-inch steel crank and H-beam rods; forged 10.2:1 JE pistons
Cylinder heads: CNC-ported Dart Pro 1 335cc aluminum rectangle-port castings with 2.30/1.90-inch Manley valves
Camshaft: Erson 238/246-at-0.050 hydraulic roller, 0.657/0.657-inch lift, 112-degree LSA
Valvetrain: Jesel 1.75:1 shaft-mount rocker and pushrods; COMP Cams valvesprings and timing set
Induction: ported Edelbrock RPM Air-Gap intake manifold, Holley 1,000-cfm 4150 carb
Ignition: MSD 6AL box, billet distributor, coil, and plug wires
Fuel system: custom stainless steel tank, Carter mechanical pump, Holley electric pump and regulator
Exhaust: Stainless Works 2-inch long-tube headers with 3.5-inch collectors, custom X-pipe, custom cutouts, dual 3-inch Flowmaster mufflers
Power adder: NOS nitrous plate system set at 200 hp
Cooling: Weiand aluminum pump, Alumatech radiator and electric fans
Output: 601 hp and 616 lb-ft at rear wheels on motor; 804 hp and 902 lb-ft at rear wheels on nitrous
Built by: owner
Transmission: Tremec TKO 600 five-speed, McLeod aluminum flywheel and twin-disc clutch
Rear axle: Ford 9-inch rearend with Strange 35-spline axles, billet yoke, 3.50:1 gears and limited-slip differential
Front suspension: Global West lower control arms, SBC upper control arms, QA1 coilovers, DSE splined sway bar
Rear suspension: Global West upper and lower control arms, QA1 coilovers, Hotchkis sway bar
Brakes: custom 12.25-inch heat-treated Coleman rotors and Wilwood six-piston calipers front and rear
Wheels & Tires
Wheels: ET 18x9.5 Classic 5, front; 18x11, rear
Tires:Toyo 275/35R18 RA1, front and 305/35R18, rear