SpeedHunters- 70s Spirit: The IMSA 240Z
The 1970s: a decade full of such automotive greatness that it’s almost impossible to sum up everything we love about it. The cars that we know from that era weren’t just fast and cool looking, they were a bit outrageous. It was a time of wide wheels, wide fenders, bright colors and production-based race cars that were routinely making two or three times the amount of horsepower they were originally designed for.
Selecting a single vehicle to represent the decade is a challenging task, but if forced to I would probably pick something like this Datsun 240Z. Maintained by the history masters at Bruce Canepa’s facility in Scotts Valley, Canepa, this Datsun is a car that truly embodies all that was great about motorsport during the ’70s.
First off, there’s the fact this car was built from a production Datsun 240Z – a model which could easily be considered one of the most important cars of the 1970s. The excitement for the Z began the moment the the new affordable sports car arrived from Japan and never really let up.
In fact, according to its background info, this particular Z actually began life as the first 240Z chassis imported to the US for the 1970 model year. That’s something hard to verify given its subsequent transformation to a race car, but whatever the case there’s a lot of history that comes with this beautiful machine.
It’s a history that would be made not on the street but on the race track. It began in 1974 when a racer by the name of Brad Frisselle formed a privateer team called Transcendental Racing. Brad had previous experience racing Datsuns, so the team chose to use the 240Z as the basis for their entry into the IMSA Camel GT series – designing, building and testing the race car from the ground up.
But of course, Brad was not alone in the venture. A very talented team of men worked to construct the car and make it competitive. An experienced builder named Dave Kent handled the body, chassis and roll cage fabrication while John Knepp of Electramotive handled the engine build.
Handling the aerodynamic design for the car was Yoshi Suzuka, who had previously worked with the BRE team, and would later go on to work with Indy Car teams, Nissan’s factory prototype program and more. At the time, such a focus on aerodynamics wasn’t too common in this type of racing – especially with a privateer team.
Another former BRE team member who worked on the build was Mac Tilton, who designed the car’s suspension system. His company, Tilton Engineering is now one of the most respected names in motorsport, with its products appearing everywhere from F1 to NASCAR.
So with the groundwork laid and a solid platform to go racing with, Frisselle tackled IMSA for the 1975 season. Along the way he took three victories and won IMSA’s Most Improved Driver Award that year.
The success was accomplished not just through Brad’s technique behind the wheel, but by the overall professional approach taken by the whole team. At the time, the Frisselle Z was considered one of the most advanced entries in the GTU class, and the Transcendental team was known as one of the most organized and detail-oriented in the paddock.
During the 1976 season the team saw even more success. Out of the eleven events they entered in ’76, they won eight of them – easily taking the IMSA GTU championship that year. What was even more impressive is that they were able to defeat the Datsun works team, which was campaigning its own Zs at the time.
Following the success with the Z, Brad continued on with a career as a team owner and driver in sports car racing, working with the Brumos team in a Porsche 935 and also campaigning a Chevy Monza in both Europe and the United States. He would also compete in the SCCA Can Am series and then drove for Mazda’s factory IMSA team before retiring from racing after the 1980 season.
Fast forward now to the early 1990s, when it was decided that the long-forgotten Datsun deserved a full restoration. Overseeing the effort would be John Cavaglieri, who served as the team’s original crew chief. That car was stripped down to bare metal and the long process began.
What’s especially cool about the restoration is that many of the original team members were involved with bringing the car back to its former glory. For example, brand new molds for Yoshi Suzuka’s body work were built and subsequently new panels were fitted to the car.
When it came to time to address the engine, the original builder, John Knepp, was called in. He proceeded to completely rebuild the triple Solex-fed L-series motor with the help of his assistant, Don Reynolds.
During the rebuild John used a number of development parts from Nissan’s GTP program, with new piston and cam designs along with fully modernized electronics. An entirely new fuel system was installed as well.
With its competition-spec rebuild. word has it the fully-built L-motor is now outputting an extremely impressive 400 horsepower.
Along with the motor, the transmission, chassis and suspension were all completely restored too.
The idea for the restoration was to give the car the same attention to detail and presentation it had while running in IMSA. The Z’s Concours-ready condition is apparent from the moment you first see it.
Like every other car that passes through the Canepa facility, the Z’s spotless condition is more reminiscent of a guarded show piece rather than a competition veteran.
Although the car began life as a 240Z, Datsun fans will probably wonder why the car has 280Z tailights. Well, IMSA rules required the race cars to have a similar appearance to production cars of the same year, thus the swapping of the 280 tail panel.
Looking inside the cockpit, the same cleanliness and attention to detail from the exterior carries over.
You can also see the updated electronics and instruments that were installed during the car’s ground up restoration.
While as much has been left period correct as possible, you’ll also find some very important upgrades made to bring the Z up to modern safety standards.
That’s something which is very important, because this car is absolutely not a museum piece.
Besides being restored to an extremely high cosmetic standard, the car was also thoroughly built to run on the track just like it did during the mid ’70s.
Today the Z can be found running at a number of vintage races, including the Rolex Reunion and the Sonoma Historics. To me it’s just awesome that the people who restore, build and race these legendary machines have no qualms about taking them out and driving them as they were meant to be.
Whether its sitting under the lights in the Canepa garage, resting in the paddock at Laguna Seca or running down the Corkscrew at full song this Datsun is out there as another reminder of what might be motorsport’s greatest era. I may not have been able to experience that amazing decade for myself, but thanks to cars like this I can certainly feel like I was right there for the glory days of IMSA.
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Brad Frisselle IMSA GTU Datsun 240Z
Race-built Nissan L-Series by John Knepp, Nissan GTP-derived cam and piston design, triple Solex carbs
Mac Tilton-designed suspension, custom chassis and roll cage fabrication by Dave Kent
Yoshi Suzuka wide-body conversion from original molds with original Transcendental Racing livery
Sparco Seats, Momo steering wheel, modernized electronics and gauges