The lovable loser. The mascot. The Rudy character if Rudy fumbled the ball. That person who can never get ahead no matter how hard he or she tries. Every family/friend group/Shakespearean play has one, and ROADKILL is no exception.
Ours is called the Rotsun.
The rotting hulk of a 1971 Datsun 240Z was pushed butt-first into the garage in Episode 25, flakes of rust showering down from its tire-stuffed hatch, unable to move under its own power, and more than likely both a biological danger and a fire hazard. It was the winter of 2014, and the mottled concerto of corrosion dubbed “Rotsun” had been sitting for more than a year at ROADKILL HQ before it was pressed into action as part of the Project Car Shootout battle royal, a test that would quickly reveal both the limits of mechanical endurance and the endurance of mechanical kludges.
In retrospect, its ignominious on-camera birth seems fitting given how much entertaining failure this hunk of barely Bondoed Japanese “steel” would bring to Freiburger, Finnegan, and the rest of us over the course of the next several years. The Rotsun became the show whipping boy, the purveyor of almost-great-but-oh-no-not-again moments that would define no fewer than a half-dozen episodes. In its early days, it also served as a lightning rod for the ROADKILL audience, with a rambunctious split between those who loved the plucky little coupe that couldn’t and those who wanted to see it put out of its misery before it could ruin another race or road trip.
The shell of the Rotsun cost $500 from White Flag Racing, where it underwent a heart transplant that swapped out its original L24 straight-six for a 4.3-liter V-6, which was sourced from a Chevy S10 pickup. This particular six belonged to Freiburger and had famously been used as a test mule for a supercharger installation over at Hot Rod almost 10 years earlier. The mill had once soared to ecstatic 500-hp heights, but it gave its life in the process, cracking the block and forcing its decade-long storage.
The motor was a gift/curse to Finnegan in 2009. He found another block for it and rebuilt the engine with CP Bullet high-compression pistons, a Comp Cams drivetrain, and a Holley carb, matching it with a five-speed gearbox pulled from another junkyard S10. The V-6 was then sent to White Flag to be mated to the Rotsun’s craggy engine bay.
Why a 240Z? Blame Finnegan. “I had one when I was in college, and it’s one of my favorite cars of all time,” he says. “It was stolen while I was bagging groceries in Diamond Bar, California.” Little did those thieves know the inspiration that would come from their crime. We still hope they all got some form of painful rash.
It was obvious from day one that the Rotsun, in its original configuration, was built to fail, but that didn’t stop Freiburger and Finnegan from making a heroic effort to prepare the car for the shootout. Pouring gas into the carb and goosing the push-button ignition yielded zero results. Once up on a lift, the full crapitude of the car became clear. The eBay-bought rearend (originally from a WRX) seemed to be holding up, but one of the car’s halfshafts had been broken then sleeved and welded over. The other side? Also broken and welded but not sleeved, which had to be taken care of right away. Oh, and there was no fuel system, either, which went a long way toward explaining the lack of joy at start-up.
The latter issue was solved by zip-tying a fuel pump to the rear end, a successful strategy that meant F&F could move on to the next problem(s): a radiator that spouted like a leaky dike, paired with the discovery that hitting the brake pedal flashed the parking lights. A new radiator installed the next morning—the day of the shootout—imparted a false sense of confidence, and the hope was that if it could make it to the parking lot where the skill-testing autocross had been set up, then everything would be OK.
In retrospect, the fact that the Rotsun (with no registration or insurance) had to be hauled on a trailer to the project car confrontation foreshadowed how it would leave. At the time, optimism was high that the 240Z could leverage its Chevy V-6 and weight advantage to shut down the Kia Rio ringer that our rivals to the death, Motor Trend, brought to the event and at least show well against its RK brethren. Finnegan’s euphoria at finally getting to show off what the Rotsun was capable of took some of the edge off of Freiburger’s assertion that it was the “most butchered ROADKILL car ever,” but it wasn’t long before DF was made to look like a prophet. After missing the first day’s filming from a dead fuel pump, the car made a single disastrously loose autocross run before it unceremoniously dumped its battery out of the tray and then welded it to the header. Dead for the afternoon, the Rotsun sat out the all-hands side-by-side drag race that ended the episode.
If the Rotsun was ever going to get one over at an autocross course on the Kia Rio—or cover more than a mile under its own power—some changes would need to be made to pretty much everything under the hood. Nothing amps up the quality and tension of a ROADKILL build like an artificially imposed deadline, so we circled the Goodguys Spring Nationals in Scottsdale, Arizona, on the calendar in Episode 26 and decided to half-ass a turbo installation on the Chevy V-6 for a rematch with the Rio.
The 295 hp being put down by the Rotsun’s 4.3-liter engine was never going to be enough for Freiburger and Finnegan, so a turbo felt like the next logical step. At the very least, forced induction would help the coupe fail both harder and faster, which is our way. Wanting to give themselves every chance to miss the starting line, the dudes picked a $250 Garrett turbo from a 7.3-liter Ford Super Duty diesel pickup as the centerpiece of the Rotsun’s rebuild, a decision that required hours of TIG welding aluminum and stainless steel together and running from shop to shop picking up the bits and pieces to get the custom V-6 header, air intake piping, and other associated hardware to play nice in the same engine bay. This was paired with a wastegate that cost more than almost every other component in the turbo system combined. The original two-day estimate turned into two weeks of solid work. The fact that not even five minutes of attention was paid to the car’s wonky suspension setup or alignment during prep for an autocross showdown tells you quite a bit about ROADKILL priorities.
Sadly, the Rotsun was unimpressed by the slick aesthetics of the turbo setup. “It’s the nicest thing we’ve ever fabricated,” Finnegan says. The first time David tried to start it up, he was met by a series of uninspiring thunks and the discovery that the No. 3 cylinder was filled with both gas and oil. Oops. Clean up on aisle Rotsun.
At Westech, the Rotsun got the oil changed just before it was strapped to the dyno and was given a successful tune on 118-octane race gas—marking the first real milestone for the hater-piped rust bucket. The end result: 387 horsepower and 430 lb-ft of torque from the mighty 4.3, along with a ton of smoke. A more modest 91-octane tune was put in place in a bid to ensure street survival, but of course that was no insurance against shenanigans, and an axle shaft snapped during parking lot burnouts on rainy asphalt just outside the shop.
Back in the shop we went to repair that and add anti-roll bars, a rear disc brake conversion, and a front brake rebuild. Oh, and we needed to weld a barn door dead bolt to the passenger-side door in a futile effort to keep it closed. Finnegan says the new hardware also serves as a theft deterrent because “who’s going to see this and go, yeah, I want inside of that car?”
Was it the hillbilly door latch that had the crowds at the Goodguys Spring Nationals throwing heaps of shade on the Rotsun as it rolled through the gate in Scottsdale? Could it have been the hater pipe sticking up through the hood, the mosquito-fumigating cloud of smoke that followed the car everywhere it went, or perhaps the sight of an import at what is traditionally a celebration of American iron? Let’s be honest: It was probably all of those things combined, and by the end of the event the Rotsun gave attendees and organizers alike even more reason to hate its rusty guts. Still, amid the bad vibes there was an oasis of goodwill in the form of a cadre of ROADKILL fans who showed up to cheer on the Japanese ode to futility in person. Under their watchful eyes—and the supervision of the tech steward—F&F installed Pep Boys seat belts in the coupe along with a few additional gauges before it was time to face down the Kia Rio for a second time.
The results were mixed. Freiburger’s first run saw him getting lost on the course, race fuel pouring out the filler door the entire way. Finnegan didn’t fare much better in the Rio, so they decided to put a ringer behind the wheel in the form of No Limit Engineering’s Rob MacGregor, a Goodguys autocross veteran who posted a blazing 77-second time in the Rotsun while further polluting the parking lot with raw oil from the hater pipe after forgetting to turn on the car’s scavenge pump.
Finnegan then compounded the mess when the Rotsun’s fan belt came off midrun and knocked an oil line free from the turbo, making the crew almost as many Goodguys friends as there were people in attendance. The next day? Redemption: Mike’s 75.055 seconds of glory in the car was good enough to beat out many late-model customs and officially take eighth place at the event. That turned out to be more than 3 seconds better than the dastardly Motor Trend Kia’s best efforts on the same course. Winning!
The Rotsun’s victory over the Rio would be the only bright spot for the car over the next two years. A few months later in Episode 32, the 240Z would receive not just a fresh turbo exhaust housing from forced induction genius Gale Banks but also a full engine-out rebuild to deal with the issues that had reared their heads at Goodguys—an effort that yielded 320 horsepower and 420 lb-ft of twist at the wheels. In a test of endurance that pitted a brand-new Subaru Legacy sedan against a motley assortment of ROADKILL projects, the Rotsun lost then won (when the Subie cut a tire) then lost again after blowing up between the parking lot and the runway before the episode-ending drag race.
With Finnegan fearing rod knock and the team distracted by the temptations of projects that run for more than a few minutes at a time, the 240Z sat idle for another year. The Rotsun got a new fan belt and some duct tape to get ready for a run at Willow Springs against Randy Pobst and the fearsome Draguar in Episode 41. With seemingly undamaged internals ready to go, the Rotsun was started up in the pits only to shake and knock itself to death on camera. Finn was right.
It seemed like the Rotsun had a death wish. That didn’t stop Finnegan from choosing it to run in a 24 Hours of Lemons race, that wonderful ode to automotive decrepitude and malaise. The guys pressed Josh Lucas Fabrication into service to handle the installation of the requisite rollcage and to fabricate new motor mounts while they took on a few other odds and ends.
A long list of needs was compiled on the most official-looking piece of cardboard we could find. These included a host of updates to the Rotsun: adding a pair of aftermarket axles for the car’s 3.90 R200 differential, replacing the engine’s rear main seal, redoing all of the wiring, and sealing up the holes in the transmission tunnel and firewall, plus a surprising series of finishing touches brought on by those pesky Lemons rules and their unfamiliar focus on safety. Also on the docket was hacking up the driver’s seat to keep helmeted noggins from touching the ceiling and installing a steel-encased fuel cell that would be completely separated from the passenger compartment.
Then there was issue of the hater pipe—another casualty of modern racing regulations, which apparently are fairly fussy about anything that blows smoke back in the driver’s face while at speed. The solution was a single side pipe that evoked the classiness of Duesenberg at the price of the most affordable stainless steel piping on the shelf.
Did any of this matter? Of course not. Once it had barely passed tech at the Buttonwillow racetrack, the Rotsun managed to complete just 22 minutes of ROADKILL’s stated 24-minute goal before having to pit after a rough-running backfire condition revealed that the car’s wastegate had broken off of the exhaust and that its fan belt had flipped up over the front due to pulley misalignment. After wrapping the fuel system in foil to fight a boil issue (and judiciously using a beer can as a spacer) and replacing the wastegate, a subsequent carb issue reared its head, forcing David and Mike to prowl through the pits in a search of a gasket for the 4150 Holley carb feeding the beast.
Running strong but suddenly unable to shift, the Rotsun returned almost immediately to the pits. With just 11 laps under its belt, the transmission had grenaded, forcing Freiburger to purchase an entire Chevrolet pickup on Craigslist in a bid to swap in a new five-speed gearbox, only to find out that it wasn’t quite the right design, or even size, to mate up with the 240Z’s V-6. With the help of a fellow racer, the team removed the shift fork controlling fifth and reverse, rebuilding the transmission overnight and leaving the car with a usable first and fourth gear. This was enough to get the car up to speed so it could blow out its water pump gasket, drop its wastegate again, fry the switch panel, and eventually, once that had all been “repaired,” finally run the last eight laps required to make a total of 24 minutes ran out of 24 hours.
These three separate but embarrassingly public (and digitally eternal) snafus sparked a desire to once and for all build a version of the Rotsun that would fail to fail. Of course, RK time being what it its, it took a full year from that fateful Subaru race until Episode 64 when the 240Z graduated from a sketchy 4.3-liter Chevy build to a slightly less sketchy 5.0-liter Ford V-8.
After a ritualistic Office Space–inspired beatdown of the poor S10 motor, it was time to strip the Craigslist ’87 Mustang GT of its still-beating eight-cylinder heart and fill the hole between the Rotsun’s front fenders.
The engine and transmission were test-fit so custom transmission crossmember motor mounts could be crafted—mounts that would have to rely on a single bolt per side due to breakage stuffing the original mounting points with snapped-off bolts. One of the primary action items was a new McLeod clutch, a part so nice it had to be installed twice when Finnegan forgot the backplating after reassembling the engine and tranny. The EFI system was also stripped off so that Finnegan and Freiburger could fit a 650 QFT blow-through carb on a Victor Jr. single-plane intake manifold.
The first problem reared its head when DF bought a Proform electric water pump so as to avoid any potential issues with aftermarket mechanical pumps. It wasn’t long before it became clear that he had outsmarted himself. The unit was super cheap and leaked constantly even after several wrappings of Teflon tape and the application of RTV. It finally took welding the fitting solid to stop the drip.
Greater success was achieved when mounting the same Powerstroke diesel turbocharger with the Banks housing that had been used on the 4.3. The position of the shock towers required flipping and angling the 5.0’s exhaust manifolds to the degree where the only logical place to mount the turbo was on a stick just ahead of and above the center point of the engine. Of course, the lack of Lemons oversight, plus the allure of convenience, meant that the hater pipe was back in full effect, tilted angrily over the engine bay like the tusk of a demented rhinoceros.
No one was more surprised than us when the Rotsun’s V-8 turbo setup fired itself into action with almost no drama. The tentative smiles soon turned into grins at a local airport where the 240Z made mincemeat of a stock Fox-body Mustang that had been brought along for comparison purposes. Its passenger door flying open at every corner, the Rotsun absolutely shredded its spiritual sibling in a straight line, a slalom, and even an improved donut marathon (despite losing a turn signal in the process). After a tense moment at the end of the episode when it seemed like the Rotsun might not fail to fail after all, it started up for the final hooning session of the day and for the very first time in its miserable existence managed to head back home from a RK challenge under its own power.
You’d think this would be a perfect time for Finnegan and Freiburger to quit while they were ahead, and you’d be right, but we aren’t known for our good decisions. The very next episode of the show featured a head-to-head battle between the ’69 Crusher Impala and the 240Z at a half-mile raceway, born from Finnegan’s unconditional love for the Rotsun and David’s equally strong belief that the supercharged big-block in the Impala could eat it for lunch.
Naturally, the prospect of going full throttle for a half mile in a car with a suspension system that’s been as casually assembled as the Rotsun’s is enough to turn any driver to religion—or in Finn’s case, to take care of all the little issues that had accumulated over time with the 240Z. This included making sure the hatch fit and latched properly, raising the carb and the charge tube up by half an inch to actually fit the (cut-out) hood, and reinstalling the scavenger pump for the turbo. A new chin spoiler was bolted to the front of the car (the original having been lost in the carnage that was Lemons), and a spoiler was strapped to the back of the car to help improve its questionable aerodynamics.
The next step was a tune on the chassis dyno at Westech. The first pull saw 482 lb-ft of torque touching the ground at the rear wheels, and after tuning, Mike could boast about a 430-hp and 493-lb-ft reading on the dyno. That’s impressive given the car weighs in at a paltry 2,566 pounds.
Prior to hitting the half mile with either beast, the pair decided that a shakedown on a more traditional dragstrip would be sensible. A road trip to Tucson Dragway was deemed in order, and although the Rotsun only had to deal with a little smoke from the evacuation pump later and then a loose alternator mount causing an unscheduled pit stop, the Impala was a disaster, causing a late arrival at their destination.
The morning of the race, however, Mike revealed that the left rear axle on the 240Z was, well, more than a little loose, a result of it unbolting itself during the overnight drive. After the axle was put back in place and a set of drag radials were installed, the Rotsun and the Impala lined up against each other for the first time. Confirming the feeling that everything had been going just a little too well, the 5.0 blew its charge tube to pieces a quarter of the way down the track, the 6 mighty pounds of boost obliterating the plastic tubing and causing the car to fall way behind the Chevy’s 11.85-second run. A rematch was in order, and true to form, the Rotsun found a new way to break hearts—by exploding the output shaft on its weak T5 transmission before gliding to a stop on the side on the drag lane.
In a way, it was a relief that the Rotsun lived up to its reputation for choking at the worst possible time because its initially flawless performance had given us all the creeps. Surprised at how good the turbo 5.0 turned out to be, DF took the engine out of the Rotsun after the Impala showdown and brought it to the lab at Westech for an episode of Engine Masters. Still featuring its stock forged pistons and roller cam and stepping up to a Holley 750 carburetor for the naturally aspirated baseline, the V-8 put out 277.9 hp and 312.6 lb-ft of torque on the engine dyno. With the turbo setup from the ROADKILL episodes back in place and running a more aggressive 15 pounds of boost, the engine made a phenomenal 617 lb-ft of twist and 550.8 hp—almost double what the motor was putting out stock.
What’s next for the Rotsun? Finnegan’s labor of love grew on Freiburger over the course of so many years of filming, and David is genuinely psyched about how well the turbo 5.0 managed to perform despite is ultra-low-buck roots. In fact, he’s recommended the unique diesel-sourced turbo setup to anyone seeking an affordable and offbeat way to get extra power from a 5.0-liter V-8.
The car has had the same enthusiasm-generating effect on the audience, and it is one of the most popular projects in the ROADKILL stable. Will we see it strut its nasty, rusty stuff for the cameras again? You betcha. Freiburger says that although the car will probably fester in the backyard for a year or two, once it comes back it’ll have to do so with gusto because the Rotsun needs a heroic win to wipe away all those failures. Finn says he knows better than to count on anything from the Rotty. “The Rotsun is like a dirtbag uncle,” he says. “You know he’s gonna get you in trouble, but you always take his calls because, for a little while at least, it’s gonna be a guaranteed good time.