Decoding the Slowness: Why Old Camaro Z28 Models Lag in Autocross

The allure of classic muscle cars, particularly the iconic Camaro, remains undeniable among enthusiasts. Yet, for those who aim to push these vintage machines on modern performance stages like autocross, a persistent question frequently arises: Why are Camaro Z28 Old models and their first-generation siblings often perceived as significantly slower than contemporary competitors? In the competitive arena of SCCA autocross and similar performance driving events, these cherished classic muscle cars frequently find themselves trailing behind more modern machinery.

This isn’t merely anecdotal observation; it sparks considerable debate within the classic car community. What exactly makes these beloved cars struggle when tasked with navigating tight, cone-defined courses? Many theories exist – is it the limitations of their outdated suspension systems, their substantial size and weight, inherent power delivery characteristics, or perhaps even the steering and braking capabilities? The reality is likely a combination of factors, and understanding them is crucial for anyone attempting to make a classic Camaro competitive in this discipline.

As a builder and tuner, a deep understanding of the platform’s inherent strengths and weaknesses is essential. By leveraging available modifications allowed within competition rules, one can strive to minimize deficiencies while accentuating strengths. While many acknowledge that Camaro Z28 Old models face challenges in autocross, the specific reasons are often debated. Some point to axle tramp in the rear suspension, others blame the front suspension, while some suspect the actual usable power output is less competitive than often assumed based on vintage ratings. The car’s size, weight, brakes, and steering ratio are also frequently cited as potential culprits.

Indeed, there are numerous potential reasons, and without extensive tuning and testing, it’s difficult to pinpoint the precise culprits. Perhaps the right build negates some issues, or perhaps some limitations are unavoidable within certain rule sets. Having identified two significant areas that commonly hold back these cars, I’ll delve into them here, with the hope that foresight and targeted efforts can mitigate their impact on my own build.

More Than Just the Machine: Driver and Tuning Expertise

One of the most significant factors contributing to the perceived slowness of many camaro z28 old models seen at autocross events is the skill level of the person behind the wheel and the knowledge applied to tuning the car for this specific type of racing. While it may sound arrogant, there’s a simple reality: success in autocross requires both proficient driving and a car properly set up for the task.

Many enthusiasts tend to overestimate their driving abilities initially. It’s only after observing or riding with truly fast drivers that the gap in skill becomes apparent. The competitive autocross scene, particularly at higher levels like SCCA, often sees top drivers gravitating towards platforms known to be competitive – modern, well-sorted Miatas, Corvettes, or the currently dominant models. These platforms are chosen because they offer the best chance of winning, which is the primary goal for competitive drivers. It’s rare to see a truly elite driver campaigning a less conventional, historically non-competitive platform like an old Camaro.

This creates a kind of self-fulfilling prophecy: because classic Camaros are seen as non-competitive, top drivers don’t drive them, and the drivers who do often get discouraged by early results and the lack of visible evidence that these cars can be competitive. This can lead them to abandon the sport before they develop the necessary driving skills. A highly skilled driver can often shave several seconds off the lap time of a beginner/intermediate driver in the same car on a typical 50-60 second course. Subtracting that “skill deficit” might make the car itself look less inherently slow.

Parallel to driving skill is the expertise in tuning and preparing the car for autocross. While the parts market for classic Camaros is vast, reflecting decades of modification efforts (originally often focused on drag racing, but increasingly on handling), there isn’t a widely accepted, optimized “spec” setup for autocross. This contrasts sharply with cars like the 1989 Civic Si in the Street-Touring class, for which detailed, successful setups have been published.

camaro car old model enthusiasts face a “deep dark hole” when starting out – countless options, conflicting advice, and the challenge of balancing streetability with performance. Without a proven baseline or prior experience tuning an autocross car, it’s understandable that many classic Camaros seen at events aren’t optimally set up. Relying solely on suspension vendors might yield results tailored to a broader demographic, not necessarily hardcore autocross performance.

My strategy to overcome this involves drawing on my experience tuning and driving various other cars. Learning on platforms that handle well out-of-the-box, like a Miata, S2000, or Corvette (preferably within SCCA events to track against known fast drivers), teaches the importance of driving technique and familiarizes one with the characteristics of a properly handling car. This experience, applied back to the Camaro, provides a better understanding of the necessary modifications and prioritizes essential components like tires and shocks over less impactful upgrades.

The Fundamental Flaw: Stock Front Suspension Geometry

Beyond driver and tuning skill, a significant intrinsic challenge for many camaro z28 old models lies in the limitations of the stock front suspension design. It is, as many enthusiasts suspect, genuinely problematic for performance handling. While numerous issues exist, one particularly detrimental aspect is the incredibly poor motion ratio.

Most classic Camaros encountered at autocross events exhibit significant body roll and front suspension behavior that appears counterproductive to generating grip.

This is not to single out any specific car or driver, but this visual illustrates a common sight: a car leaning heavily, with the front suspension seemingly struggling to maintain optimal tire contact and geometry during cornering. Even historical examples, like a 1967 Z28 featured in a magazine article, show similar characteristics despite the era’s less capable tires.

Front grip is paramount in autocross. Unlike track racing where excessive power might compensate for understeer, autocross demands rapid changes in direction and significant yaw (rotation). The front tires handle the majority of this work, and the front suspension’s primary job is to keep those tires happy and effectively loaded.

A common mistake seen on classic Camaros modified for performance is inadequate front tire width. Enthusiasts may spend heavily on components like aftermarket subframes, expensive shocks, and lightweight wheels, only to wrap them in relatively narrow 245mm tires, often paired with significantly wider tires (like 335mm) in the rear. While such stagger might suit rear-engine cars like a Porsche 911, it’s a recipe for terminal understeer and a frustrating driving experience in a front-heavy car like a Camaro (typically around 55% front weight). To make these cars turn effectively, they need as much front wheel and tire as can possibly be fitted. Modern DOT-approved tires in widths like 285mm or even wider (recalling a Viper running 335s upfront with similar front weight) are highly beneficial, though packaging challenges exist.

nice old muscle cars are great, but their original designs were not optimized for cone dodging.

The Shocking Truth: Understanding the Motion Ratio

Let’s focus on the concept of the motion ratio, which is particularly poor on the stock classic Camaro front suspension. For those unfamiliar, the motion ratio is the relationship between how far the wheel travels vertically compared to how far the shock absorber or spring compresses/extends. A higher motion ratio (closer to 1:1) means the shock/spring moves almost as much as the wheel, which is generally more effective for control.

Consider a stock ’67 Camaro lower control arm. The pivot point is at one end. The shock and spring attach somewhere along the arm, and the lower ball joint (where the wheel assembly pivots) is at the outer end.

Detailed view of vintage Camaro lower control arm measurement for motion ratio calculation

Using the approximate measurements from the photo (pivot to shock mount ~9 inches, pivot to ball joint ~16 inches), we can calculate the motion ratio:

Motion Ratio = (Distance from inner pivot to spring/shock attachment) / (Distance from inner pivot to lower ball joint pivot)
Motion Ratio ≈ 9 inches / 16 inches = 0.5625

This means for every inch the wheel moves up or down, the spring and shock only move about 0.5625 inches. This motion ratio is significantly lower than what’s found on modern, well-designed suspension systems. For comparison, look at the front corner of a modern performance car like a Viper:

Modern Viper front suspension showing spring/shock placement for high motion ratio

The spring and shock on the Viper attach much further out on the control arm, much closer to the lower ball joint, resulting in a motion ratio closer to 1, which is considerably better.

The low motion ratio on the Camaro is detrimental because shocks rely on velocity (how fast they move) to effectively damp suspension oscillations. If the shock moves only half as much as the wheel, it’s operating at half the velocity for a given wheel speed. The more shock travel per unit of wheel travel, the better the shock can control even small movements, leading to more consistent tire loading and ultimately more grip and faster cornering. Shocks on a modern performance car might be designed to operate optimally around 3 inches/second of shaft velocity for typical autocross movements. With the Camaro’s 0.5625 ratio, those same wheel movements translate to only about 2 inches/second of shock velocity. Achieving accurate, forceful damping at such low shaft speeds with commonly available shocks is very difficult.

The Knock-On Effects: Spring Rates and Geometry Issues

The problems caused by the poor motion ratio extend beyond shock effectiveness. To understand this, we need to think about “wheel rate” – the effective stiffness of the spring at the wheel – which takes the motion ratio into account. Wheel rate is calculated by squaring the motion ratio and multiplying it by the spring rate:

Wheel Rate = (Motion Ratio)² * Spring Rate

For the classic Camaro, this means Wheel Rate = (0.5625)² Spring Rate ≈ 0.316 Spring Rate. So, a 100 lb/in spring at the shock translates to only about a 31.6 lb/in spring stiffness at the wheel.

old american muscle often require extreme measures to achieve modern handling characteristics.

A more useful metric for comparing suspension stiffness between different cars, regardless of design, is natural frequency (often measured in Hertz – Hz). Target natural frequencies vary, but a starting point for a serious “race car” might be around 2.0 Hz, with higher frequencies (2.5+ Hz) common in competitive setups.

Let’s use an example: a competitive Street Touring car like my former 240sx, with a strut-based front suspension providing a motion ratio around 0.96. Running a 550 lb/in front spring resulted in a wheel rate of approximately (0.96)² * 550 ≈ 508 lb/in. With the corner weight, this yielded a natural frequency around 2.7 Hz – quite stiff but effective on street tires.

Orange Nissan 240sx autocross car used as a handling benchmark

Now, applying this to the classic Camaro’s situation. To achieve that same ~500 lb/in wheel rate, you’d need a spring rate of approximately 500 / 0.316 ≈ 1582 lb/in! Even with such incredibly stiff springs, the natural frequency would still only be around 2.5 Hz, slightly softer than the 240sx example. To reach a frequency closer to the 240sx’s 2.7 Hz, springs upwards of 1800 lb/in would be required!

1970 camaro ss 396 and other high-performance variants from the era share these fundamental suspension challenges.

These are astronomically high spring rates for a conventional suspension setup. The highest rates commonly seen on classic Camaros modified for handling were often around 800 lb/in, resulting in a wheel rate of only about 250 lb/in – roughly half the benchmark.

This brings us to the second major consequence: excessive suspension travel. At lower, more conventional spring rates, the poor motion ratio means the suspension compresses/extends significantly more than it would with a better ratio for the same wheel rate. This increased travel exacerbates the negative effects of other geometry issues inherent in the stock design, such as unfavorable camber curves (how camber changes with suspension movement) and bump steer (how toe changes with suspension movement). With large amounts of travel, even small geometric imperfections lead to significant changes in tire alignment, reducing grip. Furthermore, this requires running the car at a higher ride height to prevent suspension components from hitting bump stops or binding, which in turn raises the center of gravity – another detriment to handling.

1967 camaro ss 396 models, as referenced in the historical context, faced these same design limitations from the factory.

The Path Forward: Addressing the Suspension Weakness

So, how can one hope to make a classic Camaro handle competitively despite these challenges? The solution lies in utilizing suspension components capable of effectively controlling the extremely high spring rates necessary to achieve competitive wheel rates and natural frequencies.

This is where high-end shock absorbers become indispensable. Shocks designed for demanding motorsports applications, such as the Koni 28-series (originally developed for high-downforce Indy cars requiring precise control at very low shaft velocities and high forces) or offerings from brands like Penske, Ohlins, Moton, AST, JRZ, and Sachs, possess the necessary damping capabilities.

High-performance Koni shock absorber used to control stiff springs on a classic Camaro build

By re-valving these high-performance shocks, they can be tuned to effectively damp the motion caused by the required multi-thousand-pound spring rates, even with the limited velocities dictated by the poor motion ratio. This allows the car to be run significantly stiffer, minimizing suspension travel. While this doesn’t fix the underlying bump steer or camber curve issues within the stock subframe design, minimizing travel means the suspension operates within a much smaller range of movement, where those negative geometric changes are less pronounced and thus less detrimental to tire grip.

This addresses one of the primary mechanical hurdles, allowing for a foundation upon which further tuning (like sway bars, alignment, etc.) can be built to improve handling characteristics significantly.

Conclusion

In summary, the perception that old camaro z28 old models and other classic Camaros are slow in autocross stems from a combination of factors. Firstly, there’s a prevalent gap in driver and tuning expertise among many who campaign these challenging platforms, compounded by the lack of a widely established “spec” performance setup. Secondly, and arguably more fundamentally, the stock front suspension suffers from a severely disadvantageous motion ratio.

This poor motion ratio mandates the use of extraordinarily high spring rates to achieve competitive wheel rates and natural frequencies. Furthermore, it reduces shock velocity, making effective damping difficult with conventional components. At lower spring rates, the resultant excessive suspension travel amplifies the negative effects of other inherent geometric flaws like bump steer and camber curves, requiring compromises like higher ride heights.

Overcoming these challenges requires a deliberate, informed approach. Gaining proficiency in performance driving on more forgiving platforms provides crucial experience. Mechanically, it necessitates addressing the suspension’s limitations head-on, primarily through the use of high-end shocks capable of controlling the extreme spring forces needed to minimize travel and operate within a less problematic geometric range.

Ultimately, while making a classic Camaro truly competitive in modern autocross against optimized contemporary designs is a significant undertaking, understanding these core issues – the driver/tuner gap and the critical suspension geometry limitations – is the first essential step towards unleashing more of the potential hidden within these iconic machines.