by Tommy Lee Byrd
A Killer Creation That is More Sophisticated Than it Appears
Let’s be honest, a late 1960s or early 1970s Nova doesn’t make the best sleeper platform because these cars have been used for countless drag cars and serious street machines. However, that doesn’t mean it can’t be done. Kurt Urban, owner of Kurt Urban Performance, set out to build the ultimate sleeper and did just that with this 1972 Chevrolet Nova. At the time of the build, he was the director of operations at Wheel to Wheel Powertrain, a shop that specialized in high-end, high-performance builds. Since this was Kurt’s personal car, he went all out when it came to fabrication and sneaky tricks, holding true to his original plans to build the sleeper that every hardcore car guy has dreamed up at some point in his life.
That dream usually starts with a big engine of some sort, but Kurt went about this build with great patience, starting by strengthening the Nova’s chassis and upgrading the suspension system to correlate with the build plans. The front subframe was the first area of focus, as the choice of engine required modifications to the crossmember. Rather than giving it a major notch, Kurt simply removed the crossmember, replacing it with chrome-moly tubing with additional bracing to keep it sturdy. He then fabricated a pair of subframe connectors to tie the front frame rails to the rear rails, and attached the connectors through the floorpan to keep them from hanging down below the rocker panels. Kurt also formed reliefs in the floorpan for the larger-than-stock exhaust piping, so it could be tucked close to the body, instead of hanging down in clear sight.
From there, he formed the roll cage tubing to fit very tightly against the inner panels, making sure to hide the tubing in every way possible. It was time-consuming work that wouldn’t be performed on a regular street/strip car, but Kurt wanted this car to be at a whole new level, when it comes to hidden potential. Take the wheel tubs for example: Kurt modified the tubs to accommodate the Mickey Thompson 295/65R15 drag radials, but altered the backseat, so it would look completely stock and fit in the original location.
For suspension, Kurt retained the leaf spring design, but swapped to a pair of Smith Racecraft mono-leaf springs, and used offset shackles from Detroit Speed and Engineering to move the springs inward. Up front, stock control arms are in place, but a pair of Afco double-adjustable shocks takes the place of the original units. Baer Serious-Street single-piston disc brakes ride on all four corners, hiding behind standard steel wheels.
Rolling stock was another important aspect of the build, as the Nova not only needed to appear stock, but it also needed to appear as a base-model, six-cylinder car. For this look, Kurt went with 15x7.5-inch front wheels, and a custom pair of 15x10.5-inch Stockton steel wheels out back. He ordered the wheels with the maximum amount of backspacing, so the wheels would appear stock from the outside. After mounting the rear wheels and drag radials, Kurt installed rim screws to keep the tires in place. If not for this tiny detail and the car’s lowered stance, this Nova would look like a complete stocker.
The Nova has no shortage of power, as it is equipped with an all-aluminum LS2 engine, which has been stroked to 402 ci, and fit with a dry-sump oiling system. Again, Kurt didn’t cut any corners with this build, so the engine is packed with high-dollar goodies, including a Callies crankshaft, Howards connecting rods, and Mahle pistons. The new bottom end, in combination with the All Pro cylinder heads, creates an 8.5:1 compression ratio, which is much lower than stock and perfect for this boosted application. The LS2 has a solid-roller camshaft with .630 inch of lift and 250 degrees of duration at .050-inch lift, which motivates the titanium intake valves and Iconel exhaust valves. Up top is an Edelbrock intake manifold, with a Wilson 90-degree elbow drawing in air from a 90-mm throttle body, which faces the rear. Kurt then installed twin superchargers from Rotrex, which feature a unique design that is one of the quietest superchargers on the market. Piping from the inlets is capped with K&N air filters, while piping from the outlets is routed to the inner fenders, where twin air-to-water intercoolers reside. From there, the piping runs in the cowl and merges at its exit point, the firewall.
The fuel system consists of a stock fuel tank, which is used for pump gas, and a custom fuel cell, which is filled with high-octane race fuel. With two Bosch fuel pumps and two sets of injectors, Kurt designed an octane-on-demand system that supplies the high-octane fuel when the primary injectors reach a particular duty cycle. A BigStuff3 ECM (electronic control module) controls all this. Kurt designed and built the stainless steel headers as well as the 3.5-inch stainless exhaust system fit with Flowmaster mufflers.
On the dyno, the engine made 1,160 hp and 825 ft-lbs of torque on pump gas. Behind the twin-supercharged LS2 is a trusty Powerglide transmission, equipped with a trans brake and an ATI torque converter that stalls to 5,000 rpm. The 2-speed automatic is set up to shift electronically, when the original horn button is pressed, while the column shifter selects all other gears. When Kurt finished the car he put it to work, driving it on the Hot Rod Power Tour and competing in the Hot Rod Pump Gas Drags and Drag Week events, where the car ran a best of 9.25 at 148 mph at Cordova Dragway Park in Cordova, Illinois. With more boost, the car is certainly capable of 8s, but the car’s weight of 3,800 pounds is a determining factor as well.
The 1968–1972 Nova platform is generally light, but when you consider all of the additional equipment on this car, you begin to see the weight pile on. Also consider the fact that the interior is all there, including two bench seats, full carpeting, and a complete dash. The interior is definitely sleeper-friendly with its column shifter, hidden gauges, and tightly tucked roll cage. Other notable sleeper details include the ratty seat cover and floor mats.
After the car made its rounds in magazines and created plenty of Internet chatter, it was sold to Dru Diesner of northern Illinois, who is the current owner. Dru says he fell in love with the car when he saw it in Hot Rod, and was given the opportunity to purchase the highly acclaimed Nova. Since its change of ownership, the car has remained in the same configuration, and mainly serves as a street machine. Dru says, “It’s amazing how many people don’t know this car is fast. It’s been in Hot Rod and all over the Internet, but people are still blown away when they look under the hood. It’s the ultimate sleeper.” With 1,160 hp and low-9-second time slips to its credit, you would be hard pressed to build a better Nova sleeper, especially when you consider the thousands of man-hours and engineering put into the extravagant buildup.