We all remember that horrendous abomination of a movie The Fast and the Furious, which serves as more comedy than does any semblance automotive documentary. There's a particular scene in which Paul Walker rushes into the speed shop and speaks the classic line, "I need one of these, the big one!" as he points to a nitrous bottle, he realizes his error and says, "Nah, make it two!" That's right, two big bottles of N2O is just what the doctor ordered to create the ultimate power-adder. We may never know if that movie truly inspired automotive technician Ryan Custodio of New Market, Minnesota, to build his '98 Corvette. In fact, he's the kind of guy that will groan heavily any time someone casually mentions the movie. Ryan works with his hands, wrenching for a living on Honda's, but would rather spend some seat-time in his built Chevrolet Corvette and here at GM High-Tech Performance that's all good in our book.
All his life Ryan loved going fast and feeling the rush of acceleration and cornering g-forces. After selling his previous car, an '86 IROC-Z with a Vortech supercharged LT1 and T56 conversion, he knew he had to fill the speed void, and quick. He found this '98 Corvette in 2003 in Fort Lauderdale, Florida. He and a buddy swiftly bought two one-way plane tickets and headed down to see the car. Ryan and his buddy had a blast driving it all the way back-it's over 1,700 miles to Minnesota. Once the exhuberance of the new purchase wore off, though, the boring, stock motor would need an upgrade. "I started doing minor mods and couldn't help but want to go faster!" It wasn't long before Ryan was tearing off the heads and installing a new cam, but that wasn't enough. Next, he started on a 427 build, using the abundant and economical LQ9 6.0L iron block as a base.
Ryan commissioned TPiS of Chaska, Minnesota, to machine the iron block and forged rotating assembly. A 4.125-inch stroke Callies crankshaft paired with Lunati Pro Series 4340 steel connecting rods and Diamond pistons gave life to his new bullet. TPiS topped the short-block with its Stage 3 hand-ported LS1 heads to make a 12.5:1 compression ratio and stay compatible with rest of the '98 equipment. Regulating the Stage 3 heads' oversized valves is a TPiS ZL-17 hydraulic roller camshaft measuring 251 duration at .050 and 0.629/0.629-inch lift with a 112 LSA, optimized for normal aspiration in the neighborhood of 600 horsepower. Of course, making that much power on motor requires a good intake, so TPiS installed its trick LS6 unit sporting a 90mm snout and throttle body. An SLP Blackwing air intake and TPiS 1.75-inch long-tube headers are located at either end of this large air pump. The exhaust gases are further directed by a Random Technology X-pipe (minus the catalytic converters), and terminated aft a set of 2.5-inch TPiS mufflers or the DMH low-profile electric exhaust cutouts depending on Ryan's mood.
To command the fueling and spark, Andy Wicks of Dynotune USA supplanted one of his signature flex fuel tunes into the stock PCM, so Ryan could utilize either E85 or the finest swill available at the nearest pump. To accommodate the added volume for the high-octane ethanol, Motron 60 lb/hr injectors were needed. Wicks also modified the spark advance to accommodate a wet single-stage nitrous system from TNT. The Power Ring delivers an extra 150 ponies with its current jets that can put him back in the seat during straight line blasts. A set of QA1 12-way adjustable shocks with stock leafs also helps transfer weight, but since it's a Corvette Ryan was obligated to lower it 2 inches to increase its attitude as he has done with the rest of the car. Case in point, the rolling stock consists of the always-classy CCW SP500 rims. Measuring 18x10 at the front and 18x11 at the rear, they allow a substantially large combination of Nitto 555R 285/35/18 road race and 305/35/18 drag radial tires.
With enough horsepower to put a grin on nearly anyone's face, a Cartek clutch and pressure plate was a must. The flywheel is from a Z06, though, the rest of the driveline is original equipment including the T56. The slight exception is a 3.73 gearset and Pfadt differential mount to reduce wheelhop. An RCI five-point harness joined to a Wolfe Racecraft six-point rollbar were also required upgrades given the power level. And while tearing into the interior, it was a good time to install gauges from Auto Meter (nitrous pressure) and Innovate Motorsports (wideband O2) to keep an eye on the vitals, and a Harris Speedworks nitrous panel has been molded into the dash to command the nitrous system. Exterior cues are not quite as utilitarian, but equally effective in making this C5 badass. A Kenne Bell hood and Caravaggio rear spoiler were painted Sebring Silver, along with the rest of the car, and are offset by an understated flame job. Credit goes to Brad Russell of Watertown, South Dakota for laying down this fine paintjob.
Though you might think with so much invested in the paint, Ryan might be afraid to fry the hides. However, he assures us the best way to break in a set of tires is with a nitrous-inspired freeway burnout. Good thing he lives in Minnesota! Though track time has been limited, he has managed to click off an 11.01 at 133 mph with a 1.7-second 60-foot time. Ryan is confident that with a little bit more practice, he can hit the 10s. In the meantime he is enjoying street driving this beast on long trips with the comfort of A/C, and without the use of a giant wing and gaudy graphics. Just a C5 with a whole lot of attitude when he wants it and none when he doesn't!
Car: 1998 Corvette
Owner: Ryan Custodio
Block: LQ9, 427 cid
Compression ratio: 12.5:1
Heads: LS1, ported and polished by TPiS, 2.08 intake, 1.60 exhaust valves
Cam: TPiS hydraulic roller, 251/251 at 0.050, 0.629/0.629-inch lift, 112 LSA
Rocker arms: Stock, 1.7 ratio
Pistons: Diamond, forged
Crankshaft: Callies, forged
Rods: Lunati Pro I-beam, forged
Throttle body: TPiS 90mm
Fuel injectors: Motron 60 lb/hr
Fuel pump: Stock with Kenne Bell Boost-A-Pump
Ignition: Stock coil-near-plug
Engine management: Stock PCM, tuned by Andy Wicks of DYNOTUNE USA
Exhaust system: TPiS 1.75-inch long-tube headers, Random Technology off-road X-pipe, TPiS mufflers, DMH electric cutouts
Power-adder: TNT Power Ring nitrous kit, 150hp
Front suspension: QA1 shocks, stock springs, control arms, sway bars
Rear suspension: QA1 shocks, stock springs, control arms, sway bars
Rearend: Stock IRS, 3.73 gears, axles, posi
Brakes: Baer Eradispeed rotors, stock calipers
Wheels: CCW SP500 18X10 front, 18X11 rear
Front tires: Nitto 555R2 285/35/18
Rear tires: Nitto 555R 305/35/18
Fuel octane: 93/105 (E85)
Best ET/mph: 11.01/133
Best 60-ft. time: 1.7
Current mileage: 78,000