Ivo Medina has always been a loyal fan of 427s. The founder and president of the Classic Camaro Association, Ivo Medina has owned 22 Camaros, his last one with the legendary Chevrolet 427ci big-block mega-mill. It was a special motor for Chevrolet, and the mere mention of its name brings memories of ruling the dragstrips and scorching the streets. It was a time when the phrase "There's no replacement for displacement" was the only rule on the road.
Chevrolet always remembered its most famous big-block engine. It was a household name (most certainly in enthusiast households), but we didn't hear much about it in the displacement-starved '80s and '90s. This all changed when the factory-sponsored Chevrolet Racing Team announced a new small-block mill for the C5-R racing program and turned to the legendary number 427 to call out its performance. According to Doug Duchardt, director of GM Racing, the C5-R was the "first-ever official factory Corvette race car" and, in recent history (1999-2004), the most successful Chevrolet race car ever. It won every race it entered in 2004, captured every pole position in every ALMS event, never required an engine change in the entire racing year, and took home both the drivers' title and the team championship.
We share with you now a story of personal tragedy and the power and resilience of the human spirit. Ivo tells VETTE he lost his son, Ivo-Randy, 2 1/2 years ago in an auto accident. Ivo-Randy was a consummate Corvette fan, and he often told his dad he should move up the Bow Tie hierarchy from the Camaro to the line-topping Vette. Ivo's wife already had a Torch Red '01 Z06, so Ivo had to live with the daily pressure to convert the family motor pool to Vette-only status. Ivo tells us that before he died, his son said to him, "You have to buy your own Corvette." But Camaros ran deep in Ivo's blood, almost as deep as family. He held out.
After mourning the loss of his son, Ivo had a change of heart, and within him rumbled a new passion to cruise in his very own Corvette. Ivo, though, was still in love with 427s. It was the motor in his last Camaro, and the defining feature of the legendary Corvette 427. Ivo tells us he loved the classic, old-school torque and horsepower of the big-block 427. He says, "If I was going to buy a Corvette, it had to have a 427 in it. There would be no other way.".
Ivo searched everywhere-the Internet, magazines, referrals, and possible leads-but he could not find a C6 Corvette with a 427 engine. Maybe Ivo's son was looking down upon him with the answer, and knowing how much his Dad loved 427s, decided to find him the motor first. And that's where our story leads.
After searching high and low for a 427, Ivo found a C5-R engine assembly from John Reese at Finish Line Performance (FLP) in Naperville, Illinois. This custom speed shop offers full engine assemblies, custom tunings, and exhaust work for C5 and C6 Corvettes. Ivo tells us the 427 was indeed a factory C5-R block, and it did not start life as an LS1, LS2, or LS6. The C5-R motor had been custom-built for a customer who did not take delivery, so now it was available to Ivo. It was as if his son was saying to him, "Dad, this is the way it's meant to be." Ivo purchased the engine and said, "Now I have to find a car to put it in!"
The techs at FLP told Ivo he was the only person they knew who had bought an engine without having a vehicle waiting for it. With that in mind, before we look at Ivo's Corvette itself, let's first scrutinize its powerplant.
The C5-R was hand-built by Scott Fulkerson of Midwest Engine Tech in Mokena, Illinois. Midwest builds high-horsepower engines for FLP and private customers domestically and internationally, even as far away as Germany. The C5-R block uses a 4.125 bore and 4.00 stroke to displace 6.997 liters (427 ci). Ivo's was outfitted with a full Lunati rotating assembly, including a crankshaft, pistons with a -17cc dish, and rods. FLP Stage 3, 66cc chamber, fully ported heads top the short-block. Head essentials include 1.7 Jesel rockers and 2.080/1.570 stainless steel valves.
The C5-R is kept cool with a Ron Davis heavy-duty radiator and Doug Rippie Motorsports oil-cooler kit. The internal engine components are lubricated with a ported oil pump. Spark travels from the coils to the NGK iridium spark plugs using Taylor custom spark-plug wires. Engine power is transferred to the DTE-braced six-speed manual by way of a SPEC Stage 5 clutch and a billet-steel flywheel. The shifter is a Hurst design and provides quick, hassle-free shifts during the most arduous speed trials.
Here begins part two of our story. Ivo had his C5-R engine, but to make his son proud, he needed to find an unbelievably special Corvette to which he could mate it. Searching the Corvette Trader Web site, Ivo fell in love with a low-mileage '01 Millennium Yellow Z06 in Virginia. It only had 1,500 miles on it-less than 300 per year. The interior of the vehicle was Mod Red, and the resulting color combination-of which approximately 150 units were built in '01-was stunning. Ivo knew he had found the perfect Corvette for him, but it was already a milestone performance vehicle. However, Ivo says he bought the Corvette solely because of its rare color combination. After all, its LS6 was not nearly powerful enough for his purposes.
Ivo drove his Z06 from Virginia to Florida, where it was turned over to Corvette tuner Anti-Venom in Seffner. Here, the respected Corvette experts performed the C5-R 427 engine install. The stock LS6 was pulled and permanently replaced with the unworldly power of the C5-R 427. Other modifications performed as part of the project included coil relocation, installation of a FAST intake and Anti-Venom/FAST 99mm throttle body, and changing out the stock fuel injectors for 42-pound replacements. Anti-Venom then toughened the look of the heads with custom billet valve covers and added a line lock to facilitate tire-scalding burnouts.
Needing even more horsepower, Ivo removed the heads and shaved their surfaces to increase the engine's compression ratio to 11.3:1. (The Chevrolet Racing Team maintained a 12.5:1 compression ratio on its C5-Rs.) He also installed an Anti-Venom specialty-a custom-ground performance camshaft. The Anti-Venom grind gives a 244/248-degree duration and a 0.617/0.647-inch lift. This cam is great for the larger-displacement 427ci motor and is designed for naturally aspirated engines not optioned with a superblower. Not just a performer, this is one mighty-sounding camshaft. Just ask the Corvette enthusiasts at NCM Z06 Fest 2005, who gave this Corvette the award of Best Cam Sound at their Annual Z06 "Cam Off." The two additional drivetrain modifications Ivo performed were a set of Comp "R" lifters to complement the vehicle's custom camshaft and an LS2 waterpump.
Ivo knew that his super creation had to sound super, too. To that end, he removed the Z06's stock manifolds and upgraded the exhaust path with Kooks 1 7/8-inch headers and an off-road X-pipe. Deliberately tuned for an aggressive sound, the system exits through a set of B&B Bullet mufflers.
Force gets to the ground via a heavy-duty DTE differential housing 3.42 gears. Goodyear Eagle F1s, size 275/35-ZR18 on the front and 315/30ZR18 in the rear, provide plenty of grip so the OE Customs Z06-style wheels can tame the track and the pavement.
The horsepower and torque measurements-a whopping 525 horses and 497 lb-ft at the rear wheels-make this Corvette a monster at the dragstrip and surprisingly easy to drive on the street. According to Ivo, "Z06s are meant to be driven, not parked in a garage. And the difference between a Z06 and my C5-R Corvette is night and day. It's outrageous. The torque is unbelievable. It's scary to hear it coming down the street and know it's not stock." Crate balls of fire, Ivo. We couldn't agree more.