Let’s cut through the noise. You’re reading this because you love driving. Not just moving from point A to B, but the actual act of it—the feel of the road, the feedback in your hands, the sound of an engine working. You’re also probably aware that building a genuinely fun car today feels harder than ever. Between emissions regulations, insurance costs that punish horsepower, and a market flooded with heavy, insulated gadgets, the pure driver’s car seems like a relic. But what if I told you the blueprint for escaping all that was written over fifty years ago? Not in a boardroom, but in a magazine project car story about a humble, overlooked European coupe: the 1970 Opel GT.
This isn’t a nostalgic piece about a great car. The Opel GT, in stock form from its American importer Buick, was deeply flawed. It was a promising shape—a Giugiaro-designed wedge with pop-up headlights—saddled with compromises that neutered its potential. Yet, in a 1970 Car and Driver project, a team did something brilliant: they accepted the regulatory reality of their time and built around it, creating a car that was fast, agile, and utterly engaging without breaking any rules. Their philosophy is more relevant now than ever. We’re going to dissect that project not as history, but as a masterclass in pragmatic performance engineering for the real world.
The Starting Point: A Canvas of Compromise
To understand the genius of the solution, you must first understand the problem. The Opel GT arrived in the U.S. as a curiosity. Under its sleek skin lived a 1.9-liter inline-four, a pushrod unit from the Opel Kadett. In its most potent European form, it made about 102 horsepower. Buick’s version, strangled by early emissions equipment and tuned for low-lead fuel, felt asthmatic. More damningly, the handling was, in the magazine’s words, like “tires were bagels on a road covered with cream cheese.”
Why? The suspension was rudimentary. The car lacked any front or rear anti-roll bar. The tires were tiny 165HR-13 units, more suited to a economy hatchback than a sports coupe. The steering, while a decent size, was disconnected from the road by a chassis that rolled and wallowed. This wasn’t a driver’s car; it was a compromise car—a styling exercise with a budget powertrain and a suspension tuned for comfort over control. Buick imported it for $3,324, a price that screamed “disposable fun.” For a project car, this is the perfect starting point. As the original team noted, if you begin with something perfect, it can only get worse. Start with something flawed, and with knowledge and a few key parts, you can be a hero.
The Core Engineering Philosophy: Work Within the System
The most critical, and today most prescient, aspect of this project was its constraint. The team wasn’t trying to build a 300-hp monster. Their goal was a “sophisticated” car that the insurance cartel wouldn’t understand. They targeted a specific, realistic power figure: 100 horsepower. Not 99, not 101. Exactly 100. They achieved this not by bolting on a wild cam or a Weber carb, but through meticulous, emissions-legal blueprinting.
What does “blueprinting” mean in this context? It means the engine was completely disassembled, cleaned, and every component measured against factory tolerances. The block was align-honed, the crankshaft polished, the cylinder head ported—the ports were carefully reshaped to improve airflow without altering the combustion chamber shape or the carburetor. The compression ratio was lowered slightly to prevent detonation on the new, lower-octane unleaded fuel. The stock carburetor, distributor, and all emissions vacuum lines remained untouched and functional. An equal-length exhaust header was fabricated, a trick learned from Formula Ford racing, to improve scavenging. The result was an engine that breathed better, revved cleaner, and made every last horsepower it could within its legal cage. It was a lesson in efficiency over brute force.
The Handling Transformation: Tires and Bars Are Everything
If the engine work was subtle, the suspension overhaul was revolutionary. The team identified two glaring deficiencies: a lack of stabilizing bars and inadequate rubber. They attacked both simultaneously, understanding that these are the highest-impact, lowest-cost modifications for any chassis.
First, the anti-roll bars. The U.S.-spec GT had none. The European models offered them, along with a limited-slip differential, but Buick’s parts department was unhelpful. The solution? A West Coast company called Super-O, which fabricated crude but effective front and rear bars. This is the project car ethos in action: when the OEM fails, the aftermarket, often a small enthusiast shop, fills the void. Adding front and rear bars dramatically reduces body roll, keeps the tires more evenly planted, and transforms the car’s balance from nervous to neutral.
Second, and more profoundly, the tires. They moved from the anemic 165s to a set of massive (for the time) E60-15 Goodyear Polyglas tires mounted on 15×7-inch Minilite wheels. This was a radical change. The 60-series sidewall is much shorter, reducing sidewall flex and improving steering response. The wider footprint increased mechanical grip exponentially. The team faced a clearance issue: the wider wheels and tires could foul the front suspension components. They solved it with careful wheel offset selection and minor hammer work on inner wheel well panels—no need for fender rolling or wide-body kits. They also lowered the suspension and changed the final drive ratio to compensate for the taller overall tire diameter. The result? A car that “corners with a combination of grip and balance that will worry Porsches to death.” This is the magic formula: sticky, wide tires and stiffened roll control. It works on a 1970 Opel GT and it works on a 2024 Mazda MX-5.
Design and Interior: Function Over Form, Mostly
The Opel GT’s exterior is a classic of 1960s design. The long hood, short deck, and pop-up headlights give it a predatory, purposeful stance even today. The project car didn’t alter this sheetmetal, respecting the original Giugiaro vision. The modifications were functional and visible: the bulging fenders from the wider tires, the lower ride height, the likely addition of a small spoiler (they were “kicking around” the idea). The vibe was “tuner,” not “restorer.” It was a working car, not a trailer queen.
The interior was a snug, driver-focused cockpit. The steering wheel was “racecar-size,” large and thin-rimmed, offering excellent feedback. The seats were basic buckets, but the team was still “experimenting with different seats,” understanding that the connection between driver and car is completed through the seat. You need to be held in place to feel the car’s limits. The rest of the dash was simple, analog, and clear—no distractions. This is a key part of the “fun car” equation: an environment that focuses your attention on the driving task, not on infotainment menus or cupholders.
Performance in the Real World: More Than a Number
Let’s be clear: 100 horsepower in a 2,200-pound car is not fast by modern standards. A new Mazda 3 has more power. But the experience is everything. The engine, now breathing freely and revving cleanly, would have a more urgent, buzzy character. The sound would be a mechanical rasp, not a muted hum. The manual transmission (standard, of course) would offer short, precise throws. The handling, transformed by the tires and bars, would be the star. The car would feel incredibly light and agile, with immediate turn-in and a neutral, adjustable balance. You could drive it at 7/10ths on public roads and be completely engaged, without terrifying yourself or attracting the wrong kind of police attention. This is the sweet spot: performance that is accessible, usable, and legal. It doesn’t need to break the speed limit to break your boredom.
Market Positioning Then and Now: The Analog Answer
In 1970, the Opel GT project was a direct rebuttal to the era’s growing regulatory and insurance pressures. It asked: “What if a fun car doesn’t have to be a gas-guzzling, insurance-crippling muscle car?” The answer was a small, lightweight, emissions-compliant coupe with brilliant handling. It was a precursor to the Japanese sports car boom of the 80s and 90s—cars like the AE86 Corolla or the first Miata, which proved that modest power and sublime handling could create a legend.
Today, that philosophy is a niche. The market is dominated by either overweight, powerful grand tourers or econoboxes. The true lightweight, analog sports car is nearly extinct. The modern equivalent of this Opel GT project isn’t a new car off the lot; it’s a used Mazda MX-5 (NC or ND), a Toyota GR86, or a well-sorted BMW 3 Series from the early 2000s. But the lesson remains: start with a light, simple platform. Focus on tires, suspension geometry, and a clean, efficient powertrain. Forget peak horsepower; aim for power-to-weight and, more importantly, feel-to-weight. The goal isn’t to win drag races; it’s to own every corner, to be completely involved in the process of driving.
The Verdict: A Timeless Blueprint
The 1970 Opel GT project wasn’t about building a perfect car. It was about building a right car for its time—and, as it turns out, for our time too. It demonstrated that the barriers to driving enjoyment are often self-imposed or exaggerated by marketing. You don’t need 500 horsepower. You don’t need a $100,000 carbon-fiber chassis. You need a coherent package: a light body, a balanced chassis, sticky tires, and a powertrain that is reliable, legal, and revs with character.
The car they named “J. Edgar Opel” (a jab at the FBI director) was a middle finger to the bureaucrats, but it was also a love letter to driving. It was proof that with a roll of masking tape, a set of tires, a few bolts, and a clear engineering goal, you could out-think the system. Today, as we face a new era of electrification, weight gain, and autonomous features, that spirit is more vital than ever. The project car isn’t about the specific parts—Super-O bars and Minilite wheels are products of their time. It’s about the mindset: diagnose the flaws, apply fundamental physics, prioritize driver feedback, and ignore the horsepower hype. That’s how you build a car that’s electrifying without a single watt of extra battery power. That’s how you make a car that’s still a joy to drive fifty years later.
The Opel GT, in its original Buick trim, was a missed opportunity. But as a project, it’s a timeless template. It teaches us that the best project car isn’t the one with the most potential on paper, but the one that teaches you the most about how cars actually work. And in the end, that knowledge is the most valuable modification of all.
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