This 1970 Nova Has Come A Long Way From Being The Hand-Me-Down


This 1970 Nova Has Come A Long Way From Being The Hand-Me-Down


A question: When you were nearing the magical age where the driver's license was almost in your grasp, how many of you started eying the family car with the hopes that you would wind up driving it the second that you were deemed fit to drive? Did you start paying more attention to how everything worked? Did you wash and detail it in a not-so-subtle message to your folks? Did that tactic work, or did you simply fork over the bills needed to convince Mom and Dad that you were ready to have a car (and that they needed to move on to something else)? If you were so lucky, here's another question: how many of you still own that car, decades on? Not many, we'll bet. The unfortunate side effect of being young and on the cusp of adulthood is that things like cars can be fleeting. They get sold, they get traded, accidents happen, or they may simply wear out after many miles and memories. We pine for them later in life, but even if you build another, it isn't that first car.

Thiessen Nova Nova right-side-nose close

Brad Thiessen doesn't have those problems. In 1974, his father brought home a three-speed, six-cylinder 1970 Chevrolet Nova back when they were just another used car on the lot. Over the next decade or so, the Nova was just the car that Brad grew up with, rode in on family trips, and saw every day in the driveway. In 1985, he bought the Nova from his father and in short order the upgrades began on his newfound high-school ride. The six-cylinder was evicted for a 350 small-block and the three-speed made way for a Muncie 4-gear unit. A Ford 9-inch rear axle spared the 10-bolt that the car came with from imminent destruction and we can only imagine the kind of hell this X-body raised. It might be a bit telling that Brad didn't mention any of that when he was telling us the Nova's story, doesn't it? But after high school, the Nova was part of a different story. "The car sat on blocks more than it was used for 25 years, due to college, raising a family, starting a career and getting involved with other forms of racing," he told us. "Then in 2014, my son Blaine and I attended Drag Week together in his 2001 Camaro SS and we got hooked on drag and drive events! At that event, I decided the Nova needed to be updated again."

Thiessen Nova Front suspension shot

In 2015, after taking the rather mild Nova for one last drive, the teardown began. After blowing the X-body apart and removing all traces of the original undercoating, subframe connectors were added and the rear wheel wheels were mini-tubbed. With the goal of keeping as much of the Nova as original as possible, modifications were selected based upon what was going to benefit the build best. This meant that the stock front subframe was fitted with a rack-and-pinion steering system, tubular control arms and the crossmember was modified for more oil pan clearance. Out back, Cal-Trac split-leaf springs would be moved inboard and leaf-spring sliders would be added. After some contemplation regarding just how fast he wanted the Nova to be in the quarter-mile, he fabricated a full SFI 25.3 cage rated up to 6.50-second elapsed times in the quarter-mile into the car for safety. Once all of the fabrication was complete, the Nova was placed onto a rotisserie and the undercarriage was painted, while the subframe and Moser 9-inch rear axle were powdercoated.

Thiessen did not want to be concerned with the issues that a stock-block LS engine would offer for the kind of build he had in mind for the Nova. A Dart LS NEXT2 cast-iron block was selected for it's tall-deck architecture, main-priority oiling system, large main cap and head studs, and six head bolts per cylinder. Bruce Serene and Hillsboro Racing Engines performed the final machining on the engine before custom Wiseco pistons with extra deck thickness fitted to Callies Ultra Enforcer rods were bolted to the Callies Ultra Billet crankshaft. The camshaft is a John Bewley custom-grind that keeps the Crower solid roller lifters thumping the pushrods into the shaft-mounted rocker arms that ride on top of the Trick Flow 245 heads that came from Brian Tooley Racing. A Holley EFI single-plane split intake manifold was modified with a custom spacer to work with the tall-deck LS engine. A custom fabricated elbow connects the throttle body to the intake manifold, and everything is designed to hide under the Nova's hood. The oiling system is particularly trick: an external Peterson Fluid Systems belt-driven wet-sump oil pump system and a custom-fabricated oil pan with hinged internal baffles keep the oil moving when it needs to move and pooled up at the sump pickup. The Comp Cams billet valve covers have valve spring oil squirters to help keep the valvesprings cooled off. With an anvil like that providing the power, Brad plans to use this basic design for years to come. An MSD Pro 600 CDI Ignition and Coil Kit provide the spark power, while a Davies Craig WP150 electric water pump, 417 Motorsports manifold, Champion crossflow radiator, and dual electric fans have the unenviable job of keeping this monster cool.

That's just the basics of the engine. Now, on to the part that makes this Nova something to behold: the power adder. The boost system starts with custom fabricated stainless log-style hot side exhaust manifolds connected to twin Borg Warner S485’s with TiAl stainless V-band housings. All of the hot and cold plumbing was fabricated to remain hidden under the hood. Boost control for the turbos comes from JGS piston-type wastegates and a blow-off valve that are all controlled by on-board compressed air via a Holley EFI HIgh Flow Dual Solenoid Boost Control Kit. A Racepak SmartWire system and Racepak Keypad switch panel control the power distribution of the Nova, and a Holley Dominator EFI with a Holley EFI Programmable 8-channel Injector Driver Module manages the whole system, with a Racepak EFI Interface Module allowing the SmartWire and Dominator to talk to each other. Since Thiessen is a data-driven individual (a lot of which has to do with his background as an engineer), the Nova provides plenty of it. Every single input port that he has available is used to monitor everything about the car, from the fuel injectors to the shock travel sensors.

The remainder of the powertrain needed to be just as bulletproof as the engine. The transmission, one of the few things that was farmed out, is a TH400 from M&M transmissions, a name well-respected in the drag racing community. The TH400 is helped out with two Earl's UltraPro oil coolers with fans. One is the regular transmission oil cooler, while the other uses an Earl's Oil Circulation Pump to cycle the transmission fluid through when the car is sitting between rounds. A QA1 carbon fiber driveshaft translates engine anger into forward motion. A RaceQuip composite full-containment seat, Stroud fire-suppression system, window net and parachute check the major safety boxes, while a custom-fabricated console and Vintage Air air conditioning keep the Nova quite comfortable inside. Holley RetroBright LED headlights are an excellent final touch, keeping the stock-ish appearance of the Nova intact. The paint is the same blue lacquer that his father laid down after his sister had a bit of an accident in the car years ago and it still shined up nicely, so it was left alone.

Thiessen Nova dash

After completing the car in September 2022, the Nova made it's first appearance at World Wide Technology Raceway as part of Hot Rod Magazine's Drag Week 2022. The original plan was to take it easy, shake the car down a little, and make sure that everything was working properly. After four runs, a soft launch and low boost pass netted a 9.03 @ 154 MPH run on a straight pass down the strip. Due to other commitments, the Nova retired out after the St. Louis date, but that was just one day at the track. With the Nova pretty much complete and the 2023 season wide open, the plan is to spend the winter finishing up minor details and tuning the car before hitting the dragstrips, in the search of a seven-second pass. Not bad for the little six-cylinder Chevy plucked off of a used car lot in 1974!

Thiessen Nova rear shot


288 Posts


3 Posts