As a young boy growing up in Buffalo, New York, Cliff Kancler spent hour upon hour building models in the basement of his family’s house. Shunning outside assistance, he liked to figure things out on his own, relishing the challenge of creating his own parts or wiring his own electrical circuit. That he grew up to become an engineer surprised no one. Similarly, the fact that he singlehandedly restored the ’69 Corvette on these pages makes absolute sense. Still, the degree to which Kancler reengineered this coupe is impressive. Beneath its stock Cortez Silver paint—which Kancler applied his own garage—is a lightweight, LS3-powered machine with a highly tuned, autocross-ready suspension.
As more or less a Corvette purist, Kancler never really imagined himself performing what some might consider a “restomod” job. You see, he’s owned this particular ’69 coupe since 1972. At that point he was newly married and just a few years into his engineering job at Lockheed Martin in San Jose, California. He had sold his Pontiac GTO to buy a wedding ring and, for the first time since he got his driver’s license, was without a performance car. Feeling sorry for him, his wife suggested they start a fund to buy his dream car—a Corvette. Having witnessed the Mako Shark show car at the New York Auto Show in 1965, Kancler had a soft spot for third-generation Vettes. After a few years of saving money, however, he and his wife were well short of the funds needed for a new C3. “The jar never got full,” he says. A ’71 Corvette stickered for $5,800; they had amassed less than half that.
Undaunted, Kancler began searching for used examples. He found one in San Francisco, where he and his wife were living at the time. It was a an L46-equipped machine with a four-speed manual transmission. The original owner had driven it out from Ohio and put in a couple years of hard use, subjecting the car to street parking in San Francisco. As a result, the Cortez Silver C3 was no beauty queen. And even then, the contents of Kancler’s piggy bank didn’t add up to the asking price. Fortunately, after explaining that $2,600 was all he had, Kancler was able to drive off in the Corvette. And, for the next few decades, he kept on driving. The ’69 served as his daily driver—for much of the time, it was his only car—shuttling Kancler to and from Lockheed Martin until 2007, when he retired. At that point, the odometer read 280,000 miles. “That’s a trip to the moon and partway back,” he notes.
During those 35 years, the car remained a reliable and entertaining servant. For most of that period, it also remained stock. Then, in the late ’90s, Kancler got getting bitten by the autocrossing bug. He became a member of the Lockheed Martin Sports Car Club, which organized autocross events in the aerospace firm’s sizable parking lots. Initially Kancler didn’t make changes to his car, but when he got a ride in his friend Rob Sigler’s modified ’68 Corvette, he saw the light. “There was no comparison between his car and mine,” he says.
In terms of performance upgrades, Kancler started with the easy stuff, such as stickier tires, then began to make changes to the cars suspension. He swapped out the stock steel rear leaf spring for a fiberglass one, installed poly bushings and fitted adjustable shocks and aftermarket sway bars. The car’s handling improved markedly, and Kancler was able to post more-competitive times at autocross events.
After a while, however, the engineer realized he was starting to run up against some limits imposed by the original C3 design. For example, the increased lateral acceleration his Corvette was generating caused noticeable frame flex, causing the hood to occasionally pop up. The addition of harness and spreader bars ameliorated this problem to a certain degree, but hardly solved them. In addition, Kancler began to realize that the stock suspension geometry was a limiting factor. Making his ’69 corner faster would require more drastic steps than the minor changes he had performed up to that point
It was a similar story on the engine front. Kancler had had a hotter cam installed on the car’s small-block V-8, as well as few smaller tweaks, so his L46 was likely generating more than its original 350 (gross) horsepower, but it didn’t have the kind of grunt necessary to edge out his autocross competition. Then oil started accumulating under a valve cover, and Kancler new the original engine’s days were numbered. It was then that he started to seriously think about treating his Corvette to a major overhaul.
Like most third-gen aficionados, Kancler held the legendary RPO ZL1 in high regard. With its all-aluminum 427 big-block and host of mandatory go-fast options, the ’69 ZL1 was, and is, the ultimate Shark. It is also the rarest, with reportedly only two being made. Not surprisingly, Kancler thought the acquisition of a ZL1-spec crate engine would be a great starting point for his project.
It took little effort to track one down, as just such an engine is available from Chevrolet Performance Parts. Digesting its price was the hard part: it would have set Kancler back a cool 20 grand, way more than he wanted to spend. So, he kept on perusing the engine catalog and found a significantly more affordable option with the added cache of being a modern design: the LS376/515, a carbureted LS3 small-block tuned to a ground-pounding 515 horses for around $7,000. “I thought that would be kinda fun to drop in,” says Kancler of the engine, which he considered a “bargain.”
Still, the decision to pull the original L46 didn’t come easy for Kancler, as he had some reservations about making such significant changes to his trusty Corvette. “When I shut the motor off for the last time,” says Kancler, “I thought, Do I really want to do this?”
Kancler pulled the body in the summer of 2011, embarking on a two-year project that ended up being fairly all-consuming for the recently retired engineer. With two restorations already under his belt, including a frame-on reworking of a ’70 Corvette and a frame-off job on a Dodge Challenger, Kancler was no neophyte, but this project was more ambitious. Plus, he knew going into it that each restoration has its own unique hurdles. When asked about what aspects of the restoration were particularly challenging, Kancler humbly replies, “Everything!”
Upon tearing down his ’69 coupe, Kancler methodically labeled all the parts. Once the frame was bare, he loaded it onto a rented trailer and hauled it to a third-party facility to be stripped down the metal and powder-coated. Aside from some trim pieces that were sent off to be refinished, the rest of the work took place in Kancler’s suburban, two-car garage in Los Altos. Mind you, this space has a hydraulic lift and benefits from a healthy assortment of tools. That said, the garage is hardly a professional restoration facility. And it’s definitely is no paint shop, yet Kancler managed to lay down a top-quality, two-stage urethane paint job on his Corvette, one he thinks is better than that found on his C6 Z06 on account of its having less orange peel.
When asked about how this was accomplished, Kancler says, somewhat dryly, it involved a lot of plastic sheeting and a big compressor. “You can’t be afraid of the job,” explains Kancler, who learned a few lessons painting the Challenger. “I didn’t need to invent the system; the paint folks already have a system.”
The only real hurdle to overcome on the body was the poor quality of the previous paint job, as the base coat kept coming off, which necessitated some re-sprays. One thing that helped the process was Kancler’s decision not fix bodywork gaps left by the factory, which would have required too much work. He felt the panels were straighter than many he’d seen on Corvettes, and left well enough alone.
Not one for working things out on the fly, Kancler spent a lot of time on this project just thinking, usually planning out the next day’s job the night before. He says the split came down to roughly 10 percent thinking and 90 percent executing. Either way, the project required a lot of time. “I would have hated to pay myself,” says Kancler. He didn’t work alone, however, as his friend Sigler, who Kancler sees as the “instigator” of the whole project, was restoring his own ’68 Corvette at the same time. They performed many of the steps at the same time, which proved helpful.
When it came time to start bolting parts back onto the frame, Kancler was judicious about what made the cut. Aside from installing a more powerful engine, he wanted to significantly improve the car’s handling characteristics and shed a considerable amount of weight. In a number of ways, these three overriding goals were mutually beneficial. The LS3 engine, for example, not only represented a big jump in output but, because of its all-aluminum construction, a steep drop in mass. Similarly, the aftermarket control arms used in the new suspension were also made out of lightweight alloy.
Kancler also reduced mass by replacing the original brass radiator with a modern aluminum unit. Swapping out the stock seats for a pair of deeply bolstered Recaros shed a fair amount of weight, too—30 to 40 pounds by Kancler’s reckoning—though the main reason for this change was to improve lateral support. (During his early autocross forays, he found the original chairs severely lacking in this regard.) All told, Kancler estimates he was able to remove 300 pounds from his Corvette, resulting in an impressively low curb weight of 2,996 pounds.
Kancler also paid careful attention to weight distribution, wanting to get as much mass off the nose as possible. Thanks to the LS3, the aluminum radiator and alloy suspension, he was able to do just that. The car actually now has more weight over the rear wheels than the fronts—something not often seen in front-engine cars—with a 47 percent/53 percent front/rear split. That Kancler determined this with his own set of corner-weight scales speaks to the importance he places on suspension setup.
Thanks to the use of aftermarket control and trailing arms, Kancler was able to change his Corvette’s suspension geometry. His main aim in doing so was to reduce bump steer, a situation that results in a change of toe and a serious degradation in handling. With bump steer well managed, body roll becomes the only real dynamic that must be confronted. Kancler does so with a pair of thick, adjustable sway bars fitted with poly bushings. The installation of a Borgeson steering rack eliminated much of the slack in the stock system; it benefits from a quicker ratio as well. A set of adjustable gas shocks round out the package.
When it came to choosing the Corvette’s rolling stock, Kancler elected to maximize performance within the boundaries of the stock fenders. He went with a quartet of 9×18-inch Fikse CNC-cut wheels shod with 275/35ZR18 Hoosier A6 DOT-spec racing tires.
Unlike first-generation Corvettes and early Sting Rays, which were saddled with mediocre drum brakes, Kancler’s ’69 coupe came straight from the factory with a set of powerful discs. Though the stock units performed flawlessly on the street and held their own on the autocross course, Kancler still elected to upgrade his car’s binders with a Wilwood setup in the course of the restoration. The rotors are no larger, but the calipers are massively more robust, with six calipers up front and four in the rear. A Wilwood master cylinder is part of the system, as are stainless-steel lines. As with just about everything else with the project, Kancler did the brake job himself, admitting that installing the hard-to-bend stainless-steel lines was difficult. “All these little things take time,” he says.
Achieving his desired handling balance took a lot trial and error on Kancler’s part, as well as a good deal of number crunching. A lot of autocross runs were made before he was happy with how the car was performing. He did more than just keep track of lap times. For example, he used a heat sensor to scrutinize the temperature patterns across the surface of individual tires to determine whether or not the suspension was maximizing their available grip. Even a trained engineer like Kancler found this process humbling. “When you do this work by yourself,” he says, “you come to appreciate what the factory does.” Still, it’s clear from the spreadsheet of data that he proudly displays that Kancler particularly enjoyed this aspect of the project.
The LS376/515 arrived on Kancler’s doorstep in, you guessed it, a wooden crate. Interestingly, it came with everything except a carburetor and a controller; Kancler had to source those items separately. Instead of the recommended 770-cfm Holley carb, he elected to go with a slightly smaller 750-cfm unit. Given the low-speed demands of autocrossing, Kancler wasn’t so concerned with peak power; instead, he was more interested in having a broad power band and lots of low-rpm torque. To this end—and to allow him to run 91-octane gasoline, as opposed to the 92-proof fuel GM Performance recommend for the larger carb—Kancler also backed off on the ignition timing a fraction. As a result, this small-block is likely producing a bit less than the advertised 515 hp, but still more than the 436 horses the LS3 generated in a C6. In addition, it’s likely making its full complement of 469 lb-ft of torque, if not more.
While completing the engine assembly turned out to rather straightforward, installing it into the rolling chassis was anything but. The main problem was not the original frame, but the aftermarket suspension Kancler had attached to it. Kancler rose to the challenge, coming up with some clever fixes, though he admits it was a little unnerving cutting into and re-welding such brand-new hardware. Once the engine was in, a new challenge arose—literally: the old hood didn’t fit over the new engine. This was not a problem he had anticipated, as the original engine was a small-block V-8 with a carburetor atop it. Why would this new setup be dimensionally different?
It’s hard to pinpoint the problem exactly, though this GM Performance engine does sport a rather tall “spider type” intake manifold and sits high on the frame mounts. Also, that big Holley carb is a fairly substantial hunk of metal. In any event, what Kancler needed was a taller engine-bay cover. He found a suitably bulged, big-block–style one on eBay.
Inside and Out
When it came to restoring the car’s interior, Kancler tried to keep as many original parts as possible. Because they were still in good condition, the dash pad and door panels were retained. Sharp-eyed readers may notice that the steering wheel is not original; it indeed has a smaller-than-stock diameter. However, Kancler’s main reason for swapping in a replacement helm was the fact that the original one broke during an autocross event. (This occurred back when he had the stock seats, and he was holding onto the wheel for dear life.) In conjunction with the quicker steering rack, he says this wheel makes for much-improved directional control in the heat of autocross battle.
Kancler did elect to comprehensively upgrade the Corvette’s electronics. The switch to an electric fuel pump and electronic engine-control unit were the main drivers of this decision, but he also wanted to improve the car’s instrumentation. Again, he did the work himself, including the building of a custom module for the fuel pump. One of the car’s cleverer bits is its iPod installation, which Kancler cleverly hid under in the center console. He was also smart enough to retain the original wiring harness. “I didn’t want to open that can of worms,” he says, while admitting he still has a bit of electrical work left to do on the car.
As with many DIY restorers—and perhaps the honest professional ones—Kancler found himself in the possession of a few left-over parts after he’d completed the car’s reassembly. And while he’s not quite sure what to do with these items, he has no plans to part with them. Interestingly, it’s a similar situation with the original 350 V-8. “I still don’t know what to do with the old engine,” he admits. But given that this small-block provided him with nearly 300,000 miles of mostly trouble-free transportation, don’t expect it to show up on Craigslist any time soon.
While the bulged hood is an obvious change to the car’s bodywork—and still a bone of contention for Kancler—it and the incorporation of late-model adjustable side mirrors are the exterior’s only departures from stock. Aside from the wheels, of course. The combination of these tall alloys and the low-profile tires that drape them significantly alters the appearance of this Corvette, giving it what many would consider a signature restomod look—that mixing of old and new. However, what Kancler has achieved is a sense of cohesion that is lacking in many such modified Corvettes. It looks all-of-a-piece, thanks in part to its monochromatic silver hue, which helps those big wheels blend into the package. The same goes for the body-color mirrors. Finally, the car’s lowered stance imbues it with an aggressive sense of purpose—as in going fast around an autocross course. And that is exactly what Kancler uses it for.
Letting it Rip
We saw Kancler and his car in action at Marina Airport near Monterey last fall. Santa Clara (California) Corvettes was hosting an autocross on an unused portion of the facility—on the very same spot where we test-drove the 2014 Corvette Stingray during its initial press event. Kancler took it easy on his first run, choosing to spend time figuring out the course. “It’s complicated out there!” he reported upon his return to the paddock area. “Things come at you really fast.”
Kancler picked up the pace on his second run, circulating the course six seconds faster. “This is fun,” he exclaimed afterwards. Even at this increased speed, the ’69 appeared resolutely planted to the concrete, exhibiting little body roll, brake dive or tail squat under acceleration. And accelerate it did. Accompanied by a robust, though not overly loud, bark from its rear-mounted tailpipes, the Corvette blasted from cone to cone in a hurry. Wheelspin did not seem to be a problem, though part of that was clearly due to Kancler’s carefully meted throttle applications: We could hear him smoothly rolling on the throttle out of corners. A fellow Corvette autocross driver couldn’t believe that, given its prodigious engine output, Kancler’s C3 only had 275mm-wide tires in the rear. Kancler explained that he was adamantly against flaring the Corvette’s rear fenders, which would have been required to fit wider rubber. For him, handling balance trumps traction, and he’s very pleased with what he has been able to achieve with 275s all around.
Kancler is careful to keep his passion for autocrossing in perspective. “It’s a hobby,” he says. “I’m in this to have fun. There’s no glory in it.” Still, given his engineering background and penchant for detail, we were surprised he didn’t fiddle more with his car between runs. No tire pressures were changed, no shocks were adjusted. What gives? “The driver’s got to get better first,” he notes, explaining that he is now able to enjoy the fruit of his previous labors, which included a whole lot of fiddling. In other words, all that hard work paid off. “The suspension is just about right; it’s pretty well balanced,” he says. “It’s a blast to drive now.” As if to prove the point, he proceeded to clip another four seconds off his time on his next run.