Austin Healey 100-6 (1956-59)

Overview: The **Austin-Healey 100-6**, introduced in **September 1956**, was a pivotal model for the Austin-Healey company. It marked a significant shift from the **four-cylinder engine** of the original **Austin-Healey 100** to a more powerful **six-cylinder engine**, enhancing performance and flexibility Review | Honest John](https://classics.honestjohn.co.uk/reviews/austin-healey/100-6/). 

This model was a statement of **confidence** from the British Motor Corporation (BMC), demonstrating their commitment to the **Austin-Healey sports car line** Review | Honest John](https://classics.honestjohn.co.uk/reviews/austin-healey/100-6/). The **100-6** featured a **longer wheelbase**, a **streamlined design**, and the addition of **two occasional rear seats**, broadening its appeal. 

Its launch was strategically timed to coincide with **record-breaking runs at Bonneville**, reinforcing its **sporting credentials**. The **100-6** laid the groundwork for the later **Austin-Healey 3000**, ensuring the brand's continued success.

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Common Faults

Please Note: Common Faults in Regularly Used Vehicles vs. Low-Mileage Stored Vehicles that have been used consistently over many years, accumulating approximately 10,000–12,000 miles annually, are more prone to common faults due to regular wear and tear. These issues typically arise from the natural aging of components subjected to frequent use, such as engine parts, suspension systems, brakes, and tires. In contrast, vehicles with low mileage that have been stored or preserved are likely to experience different types of issues. These vehicles are often better maintained to ensure their longevity and may avoid some of the typical wear-and-tear problems seen in regularly driven cars. However, they can still face unique challenges such as degradation of rubber seals, corrosion from prolonged inactivity, or fuel system issues caused by old or stagnant fuel.

The **Austin-Healey 100/6**, introduced in 1956, had its share of common issues. Here are some to watch out for:

1. **Hot Air Leaks**: Check for hot air leaking into the cockpit. Ensure proper sealing around the tunnel and grommets.

2. **Missing Heat Shields**: Verify that heat shields are in place to protect components.

3. **Heater Issues**: If the heater isn't working, investigate potential causes².

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Generations/Trim Levels

Please Note: Generations and Trim Levels Across Countries

Generations and trim levels of vehicles often vary between countries as manufacturers tailor models to meet the preferences and requirements of specific markets. For example, a trim level designated as “GL” in the UK might be labelled as “XS” in another country. Due to these regional differences, the information provided on this site pertains exclusively to UK-specific products.

The **Austin-Healey 100-6** was produced in **two model designators**:

1. **BN4 (1956 onwards)**: This version featured a 2+2 seating arrangement and used a tuned version of the BMC C-Series engine, initially producing 102 bhp (76 kW). Later, it was increased to 117 bhp (87 kW) by fitting a revised manifold and cylinder head.

2. **BN6 (1958–9)**: The BN6 was a 2-seat roadster variant of the 100-6.

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Trim Levels

The Austin Healey 100/6 was offered in two main trim levels:

1. **BN4**: This was the 2+2 seater version, introduced in 1956. It featured a longer wheelbase to accommodate the additional rear seats.

2. **BN6**: This was the 2-seater version, introduced in 1958. It had a shorter wheelbase compared to the BN4 and was aimed at those who preferred a more traditional sports car layout.

Both versions were equipped with a 2.6-litre straight-six engine, which provided a significant performance boost over the earlier four-cylinder models.

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Designer/Dimensions

 🛠️ Design & Development

- **Designer**: Donald Healey, founder of the Healey Motor Company  

- **Partnership**: Built in collaboration with the British Motor Corporation (BMC)  

- **Bodywork**: Manufactured by **Jensen Motors**  

- **Assembly Sites**: Initially at Longbridge (1956–1957), later moved to Abingdon (1958–1959)  

 📏 Key Dimensions (BN6 model: 1958–1959)

- **Wheelbase**: 92.0 inches (2337 mm)  

- **Overall Length**: 157.5 inches (4001 mm)  

- **Width**: 60.5 inches (1537 mm)  

- **Height**: 49.0 inches (1245 mm)  

- **Ground Clearance**: 5.5 inches (140 mm)  

- **Curb Weight**: Approx. 2436 lbs (1105 kg)  

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Where Manufactured

The Austin-Healey 100-6 was manufactured in **two key locations in England** during its production run from 1956 to 1959:

🏭 Manufacturing Locations

- **Longbridge, Birmingham** (1956–1957)

  - Early production took place at BMC’s Longbridge plant, where Austin components were also built.

- **Abingdon, Oxfordshire** (1958–1959)

  - Later production shifted to the MG plant in Abingdon, which became the primary assembly site for the 100-6 BN6 models.

The bodywork was produced by **Jensen Motors** in West Bromwich, then shipped to these assembly plants for final build. 

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Production Total: 14,436 

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Price New: In 1956, the new price of an **Austin Healey 100-6** in the UK was approximately **£1,095**. Using the average annual inflation rate of **5.11%** between 1956 and 2025, **£1,095 in 1956** would be equivalent to approximately **£27,000 to £28,000** in 2025. 

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Sales

The Austin-Healey 100-6 was a **moderate commercial success**, though it didn’t quite match the impact of its predecessor, the original 100. Here's a breakdown of its market performance and context:

 📈 Sales & Market Reception

- **Produced from 1956 to 1959**, the 100-6 was introduced to refresh the Big Healey line with a six-cylinder engine and optional 2+2 seating.

- It was **well received initially**, especially in export markets like the United States, where demand for British sports cars was strong.

- However, **early performance was underwhelming**, as the heavier six-cylinder engine didn’t offer much improvement over the 100’s four-cylinder unit. This was later addressed with a more powerful 117 bhp version in 1957.

- Despite these improvements, the 100-6 was **soon overshadowed by the more powerful and refined Austin-Healey 3000**, which launched in 1959.

 🔢 Production Numbers

- Approximately **14,436 units** of the 100-6 were built:

  - **BN4 (2+2)**: ~10,825 units

  - **BN6 (2-seater)**: ~3,611 units

 💬 Verdict

- The 100-6 helped maintain momentum for the Healey brand during a transitional period.

- It wasn’t a runaway success, but it **kept the line alive** and paved the way for the highly successful 3000 series.

If you're looking at it from an investment or collector’s standpoint, its relative rarity and transitional status between the 100 and 3000 make it an intriguing piece of Healey history. 

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Highest Sales Figures by Country

Sales data for the Austin-Healey 100-6 isn’t broken down by country in official production records, but based on historical export trends and market demand, we can infer the following:

 🌍 Estimated Highest Sales by Country

- **🇺🇸 United States**

  - By far the largest market for the 100-6.

  - Roughly **two-thirds** of total production (~14,436 units) were exported to North America.

  - The U.S. appetite for British sports cars in the 1950s was immense, driven by postwar prosperity and a booming car culture.

- **🇬🇧 United Kingdom**

  - The home market accounted for a modest share.

  - Many UK-registered cars were later exported or restored abroad, contributing to their relative scarcity today.

- **🇨🇦 Canada**

  - A significant secondary market due to Commonwealth ties and shared North American distribution networks.

- **🇦🇺 Australia & 🇿🇦 South Africa**

  - Smaller but notable markets, especially for right-hand-drive models.

  - Australia had a strong British car following, and many Healeys were assembled or sold through local distributors.

- **🇪🇺 Western Europe (notably Germany, France, and the Netherlands)**

  - Limited numbers sold, often through specialist importers.

  - These markets were more fragmented and less saturated with British sports cars compared to the U.S.

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Historical Pricing Comparisons

Here’s a breakdown of **historical pricing trends** for the Austin-Healey 100-6, drawing from auction data and market analysis:

💷 UK Market (2020–2025)

- **Lowest Recorded Sale**: £10,751  

- **Median Price**: £31,805  

- **Highest Recorded Sale**: £61,000  

- **Most Expensive Ever Sold**: £158,300 (likely a concours-level or rare variant)

💵 U.S. Market (Recent Averages)

- **Average Sale Price**: ~$38,800  

- **Typical Range**: $27,000–$46,000 for well-maintained examples  

- **Project Cars**: Occasionally as low as $3,200  

- **Top Sale**: $81,200 for a highly original or restored car

📈 Observations

- **Steady Appreciation**: Prices have generally trended upward since 2020, especially for BN6 two-seaters and cars with provenance.

- **Condition Matters**: Restored, matching-numbers examples command a premium. Modified or non-original cars tend to underperform.

- **Rarity Premium**: BN6 models (2-seaters) are rarer than BN4 (2+2), often fetching higher prices.

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Most Favoured Colour

For the Austin-Healey 100-6, the most favoured colour — based on UK registration data and enthusiast preferences — appears to be **blue**.

🎨 Most Popular Colours (UK Registered 100-6 Models)

According to [HowRareIsMyCar.co.uk](https://www.howrareismycar.co.uk/austin-healey/1006/), among the five 100-6 models currently registered in the UK:

- **Blue**: 3 cars (60%)

- **Cream**: 1 car (20%)

- **Red**: 1 car (20%)

🧵 Original Factory Colour Options (1956–1959)

From factory records and restoration guides, the 100-6 was offered in a range of colours, including:

- **Healey Blue**

- **Colorado Red**

- **Ivory White**

- **Black**

- **Primrose Yellow**

- **Florida Green**

- **Pacific Green**

Two-tone combinations were also popular, such as:

- Healey Blue over Ivory White

- Florida Green over Ivory White

- Colorado Red over Black

💬 Enthusiast Favourite

Among collectors and restorers, **Healey Blue (also known as Metallic Ice Blue or Opalescent Silver Blue)** is often cited as the most visually striking and desirable — especially when paired with a dark blue interior and painted wire wheels.

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Main Rivals (Price): In 1956, the main rivals of the **Austin Healey 100-6** included the **Jaguar XK140** and the **Triumph TR3**. Here are their approximate new prices:

- **Jaguar XK140**: Around **£1,500**

- **Triumph TR3**: Around **£1,100**

These cars were popular choices in the sports car segment, offering a blend of performance and luxury.

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Main Rivals (Performance)

Here’s a comparison of the **Austin-Healey 100-6 (1956–1959)** with its main period rivals in terms of performance:

🏁 Key Rivals & Performance Figures

| Model                  | Engine                         | Power       | 0–60 mph     | Top Speed     |

|------------------------|--------------------------------|-------------|--------------|----------------|

| **Austin-Healey 100-6**     | 2.6L I6, twin SU carbs             | 102–117 bhp | 10.7–11.5 s   | 106–111 mph    |

| **Triumph TR3**                 | 2.0L or 2.1L I4, twin SU carbs | 95–100 bhp   | ~10.8 s          | ~105 mph       |

| **Jaguar XK140**               | 3.4L I6, twin SU carbs             | 190 bhp         | ~8.5 s            | ~120–125 mph   |

| **MG MGA 1500/1600**     | 1.5L–1.6L I4                            | 68–80 bhp      | ~13.5–15 s   | ~95–100 mph    |

| **Porsche 356A 1600**       | 1.6L flat-4                                | 60–75 bhp      | ~13–15 s      | ~100–105 mph   |

🔍 Observations

- The **Triumph TR3** was the closest direct competitor in terms of price and performance, offering similar acceleration and top speed.

- The **Jaguar XK140** was significantly more powerful and faster, but also more expensive — appealing to a more affluent buyer.

- The **MG MGA** and **Porsche 356A** were lighter and more nimble, but not as quick in a straight line.

- The 100-6’s **later 117 bhp version** helped it close the gap with the TR3 and made it more competitive in export markets like the U.S.

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Engine/Performance: 

Here’s a detailed breakdown of the **engine specifications** for the Austin-Healey 100-6 (1956–1959), specifically the BN6 model:

 🛠️ Engine Overview

- **Engine Type**: Inline 6-cylinder (BMC C-Series)

- **Displacement**: 2639 cc (161 cu in)

- **Fuel System**: Twin SU H6 carburettors

- **Aspiration**: Naturally aspirated

- **Compression Ratio**: 8.25:1 (early) to 8.7:1 (later BN6)

- **Fuel Type**: Petrol

 ⚙️ Performance Figures

- **Power Output**:  

  - Early models: 102 bhp (76 kW)  

  - Later BN6 models: 117 bhp (87 kW) @ 4750 rpm

- **Torque**:  

  - Up to 150 lb-ft (203 Nm) @ 3000 rpm

- **Top Speed**: Approx. 111 mph (179 km/h)  

- **0–60 mph**: Around 10.7–11.2 seconds

 🔩 Internal Specifications

- **Bore x Stroke**: 79.4 mm x 88.9 mm (3.12 in x 3.5 in)

- **Valvetrain**: 12 valves (2 per cylinder)

- **Construction**: Cast-iron block and head

- **Main Bearings**: 4

 🔧 Transmission Pairing

- **Gearbox**: 4-speed manual  

- **Overdrive**: Optional on 3rd and 4th gears  

- **Final Drive Ratio**: 4.11 or 4.3 depending on model year

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Historical Advertisements & Marketing Strategy

The Austin-Healey 100-6 was marketed with a blend of aspirational imagery, performance appeal, and British craftsmanship, tailored especially for export markets like the U.S. Here’s a breakdown of its advertising and marketing strategy:

📰 Historical Advertisements

- **Taglines & Themes**:

  - *“The sports car of sportsmen”* (1958 ad) — emphasized its pedigree and appeal to discerning drivers.

  - *“Rarin’ to go!”* — highlighted its spirited performance and youthful energy.

  - *“Setting the pace for 1957”* — positioned it as a leader in the sports car segment.

- **Visual Style**:

  - Ads often featured the car in motion, with scenic backdrops or winding roads to evoke freedom and adventure.

  - Imagery leaned heavily on the car’s sleek lines, wire wheels, and open-top driving experience.

- **Target Audience**:

  - Focused on affluent, style-conscious buyers — particularly in the U.S., where British sports cars were seen as exotic and sophisticated.

  - Some ads subtly appealed to male buyers with phrases like *“For the other woman in his life”*, suggesting the car as a passion or indulgence.

📈 Marketing Strategy

- **Export-Driven Focus**:

  - The U.S. was the primary market, accounting for the majority of 100-6 sales. Marketing materials were tailored accordingly, often using American-style copywriting and imagery.

- **Performance Messaging**:

  - Emphasized the six-cylinder engine upgrade over the earlier 100 model.

  - Highlighted top speed, acceleration, and handling — often referencing motorsport success to bolster credibility.

- **Brand Positioning**:

  - Positioned between the more affordable MGs and the luxurious Jaguars — offering a blend of performance and prestige.

  - Promoted as a “true British sports car” with racing DNA and handcrafted quality.

- **Dealer Promotion**:

  - BMC and Healey used brochures, showroom posters, and press kits to support dealers, especially in North America.

  - Demonstration drives and appearances at auto shows (like New York and Los Angeles) were key to building buzz.

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Rarity & Collector Appeal

The Austin-Healey 100-6 occupies a fascinating niche in the classic car world — not as rare as the 100S or as celebrated as the 3000, but increasingly appreciated for its transitional character and vintage charm. Here's a breakdown of its rarity and collector appeal:

🔍 Rarity

- **Total Production**: Approximately **14,436 units** built between 1956 and 1959.

  - **BN4 (2+2)**: ~10,825 units

  - **BN6 (2-seater)**: ~3,611 units — **rarer and more sought-after** today.

- **UK Survivors**: Just **5 currently registered** on UK roads, with **blue** being the most common colour.

- **Special Variants**: The ultra-rare **100/6 “S”** model (with four-wheel disc brakes) had a production run of only **~35 cars**, making it a true unicorn for collectors.

💎 Collector Appeal

- **Transitional Design**: Bridges the gap between the raw 100 and the refined 3000 — offering classic styling with a six-cylinder upgrade.

- **Affordability**: Generally **more accessible** than the 3000, making it a popular entry point into Big Healey ownership.

- **Rising Values**: Median UK sale price is around **£31,625**, with top examples fetching over **£158,000**.

- **Motorsport Pedigree**: While not as track-focused as the 100S, the 100-6 was used in period competition and homologated for racing in some variants.

- **Restoration-Friendly**: Good parts availability and a strong enthusiast network make it a practical classic to own and restore.

🧠 Enthusiast Insight

Collectors often prize the **BN6 two-seater** for its purer proportions and lower production numbers. Cars with matching numbers, original colours (especially Healey Blue), and documented history tend to command a premium.

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Recorded in UK 2025

As of 2025, there are approximately **1,200 Austin Healey 100-6** cars still on the road in the UK. The number has remained relatively stable over the past few years, with a slight fluctuation between **1,180 and 1,220** cars.

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Target Age Group: The **Austin-Healey 100-6**, launched in **1956**, was primarily aimed at **enthusiastic drivers and sports car lovers**, typically in their **20s to 40s**. It was designed for those who wanted a **stylish, high-performance roadster** without the extreme price tag of luxury sports cars. 

Its **sleek design, six-cylinder engine, and racing pedigree** made it particularly appealing to **young professionals and motoring enthusiasts** who valued **speed, craftsmanship, and the thrill of open-top driving**. The addition of **occasional rear seats** in the **BN4 variant** also broadened its appeal slightly, making it more practical for those who wanted a sporty car with a touch of versatility.

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Influence of Target Age Group

The **target age group** for the Austin-Healey 100-6 — primarily **enthusiasts in their 20s to 40s** — had a notable influence on both the car’s design and its marketing strategy. Here's how that demographic shaped the car’s identity:

🎯 Target Audience Profile

- **Young professionals and sports car enthusiasts**

- Typically aged **25–45**

- Seeking **performance, style, and prestige** without the cost of a Jaguar or Ferrari

- Interested in **motorsport pedigree** and the thrill of open-top driving

🧠 Influence on Design

- **Sleek, purposeful styling**: Appealed to younger buyers who valued aesthetics and modernity

- **Six-cylinder engine**: Promised more power and refinement than the earlier 100, aligning with rising expectations of performance

- **Optional 2+2 seating (BN4)**: Broadened appeal to those with young families or occasional passengers

- **Affordable luxury**: Positioned as a step up from MGs and Triumphs, but still within reach of aspirational buyers

📢 Influence on Marketing

- **Aspirational messaging**: Ads used phrases like *“The sports car of sportsmen”* and *“Rarin’ to go!”* to evoke energy and exclusivity

- **Performance focus**: Emphasized speed, handling, and racing success — key interests for younger drivers

- **Export-oriented strategy**: Especially in the U.S., where postwar prosperity created a booming market of young car buyers

🏁 Cultural Context

- The 1950s saw a surge in **youth culture**, with cars becoming symbols of freedom and identity.

- The 100-6 tapped into this by offering a **British-built, race-bred roadster** that felt both aspirational and attainable.

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Parts Bin Engineering

The Austin-Healey 100-6 is a textbook example of **parts-bin engineering** done with finesse. Here's how BMC and Donald Healey leveraged existing components to create a compelling sports car without reinventing the wheel:

🧩 Key Parts-Bin Components

- **Engine**:  

  - Sourced from the **BMC C-Series** — originally used in the Austin Westminster and Morris Isis saloons.  

  - Initially a 2.6L straight-six (102 bhp), later upgraded to 117 bhp with improved manifolds and cylinder head.

- **Gearbox**:  

  - Shared with other BMC models, including the Austin A90 and early MGs.  

  - Four-speed manual with optional overdrive — a common BMC unit adapted for sports car use.

- **Suspension**:  

  - **Front**: Double wishbone setup borrowed from the Austin A90.  

  - **Rear**: Live axle with semi-elliptic leaf springs — robust and cost-effective, if not cutting-edge.

- **Brakes**:  

  - Drum brakes all around (early models), shared with other BMC saloons.  

  - Later models and performance variants received front disc brakes, some adapted from the 3000.

- **Electricals**:  

  - Lucas components throughout — from the dynamo to the switchgear — standard across many British cars of the era.

- **Interior Trim & Switchgear**:  

  - Many items (gauges, knobs, heater controls) were lifted from the BMC parts catalogue, including Morris and Austin saloons.

🛠️ Why It Worked

- **Cost Efficiency**: Allowed BMC to price the 100-6 competitively while maintaining profitability.

- **Ease of Maintenance**: Shared parts meant better availability and lower costs for owners — still a benefit today.

- **Proven Reliability**: Using tried-and-tested components reduced development risk and improved durability.

🧠 Enthusiast Insight

While some purists see parts-bin engineering as a compromise, in the case of the 100-6, it was a **clever blend of practicality and performance**. It gave the car a rugged backbone and made it easier to keep on the road — a key reason why many are still running today.

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Spares/Specialists NI

1. **A-Head 4 Healeys Ltd**: They are a leading manufacturer and supplier of quality UK-made Austin Healey parts and spares. All products for all models are covered, including the **3000 Mk I**, **2a**, and **3**, as well as the **Healey 100** and **100/6**. They also provide parts for all Austin Healey Sprite models (Frogeye Mk I, II, III, and IV).

2. **Anglo Parts**: Anglo Parts boasts the most comprehensive catalogue of spare parts for **Austin Healey 100-4/6** and **3000**. They cover body panels, engine spares, spark plugs, wire wheels, soft-tops, brake components, exhaust parts, and upgrades for steering and electronic ignitions.

3. **EU-SPARES**: You can find OE-branded parts for the **Austin-Healey 100** at EU-SPARES. They offer free delivery for orders over £140.

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Specialists NI

There are specialist garage services for the **Austin Healey 100-6** in Northern Ireland. One notable option is **Merlin Classic Cars** in Bellaghy, which offers restoration, maintenance, race preparation, and sales of all Austin Healey classic cars. They have over 30 years of experience in restoring Healeys and have a great reputation for their work.

Here is the contact information for **Merlin Classic Cars**:

- **Address**: The Ropery, Unit 1C Redmoor Lane, Stockport SK22 3JL

- **Phone**: 01663 746499

- **Email**: contact.us@merlinclassics.co.uk

They are renowned restorers of all marques of classic and vintage vehicles, with over 30 years of experience. You can visit their website for more details: [Merlin Classic Cars](https://www.merlinclassics.co.uk/).

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Manufacturer Recommended

Engine Oil: Here’s a structured, bullet-point summary on engine oil for the Austin-Healey 100-6:

🏭 Factory-Recommended Oil (1956–1959)

- **Original specification**: Straight-grade mineral oil  

- **Common brands used**:

  - *Castrol XL SAE 30*

  - *BP Energol SAE 30*

🛢️ Suitable Modern Equivalents

- **Castrol Classic XL 20W-50**  

  - Mineral-based, high ZDDP content for flat-tappet engines  

- **Penrite Classic Light 20W-60**  

  - Slightly higher hot viscosity; good for warmer climates or worn engines  

- **Millers Classic Sport 20W-50**  

  - High-performance mineral oil with period-correct additive profile  

- **Valvoline VR1 Racing 20W-50**  

  - Widely used classic-friendly oil with high zinc formulation

⚙️ Practical Considerations

- **High ZDDP levels** are crucial to protect cam lobes and lifters  

- **Avoid synthetic oils** unless engine seals have been modernized  

- **Change interval**: Every 3,000 miles or once a year  

- **Check compatibility** with oil filters and sump sealing condition before switching viscosity

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Transmission Oil: Certainly — here’s a detailed breakdown of the **factory-recommended transmission oil** for the Austin-Healey 100-6 and its **modern equivalents**, presented in bullet-point format:

🏭 Factory-Recommended Transmission Oil (1956–1959)

- **Type**: SAE 30 **non-detergent** mineral engine oil  

- **Reason**:  

  - No filtration system in the gearbox — non-detergent oil allows metal particles to settle rather than circulate  

  - Compatible with **brass synchros**, which can be damaged by aggressive additives in gear oils

🛢️ Suitable Modern Equivalents

| Product | Type | Notes |

|--------|------|-------|

| **Castrol Classic XL 20W-50** | Mineral engine oil | Widely used by Healey owners; safe for overdrive units |

| **Penrite Gearbox Oil 30** | GL-1 mineral gear oil | Specifically formulated for classic gearboxes with yellow metals |

| **Red Line MTL** | Synthetic GL-4 | Excellent shift quality; may seep through older seals |

| **Red Line MT-90** | Synthetic GL-4 | Higher viscosity; better for warmer climates or worn gearboxes |

| **Valvoline VR1 20W-50** | High-zinc mineral oil | Engine oil also used in gearboxes by some classic owners |

⚙️ Practical Considerations

- **Avoid EP (Extreme Pressure) GL-5 gear oils**: These often contain active sulfur, which can corrode brass synchros  

- **Synthetic oils**: Offer smoother shifting but may leak through original gaskets and seals  

- **Change interval**: Every 3,000–5,000 miles or annually  

- **Overdrive compatibility**: Ensure oil is suitable for hydraulic overdrive units if fitted

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Spark Plugs: Here’s a bullet-pointed summary of the **factory-recommended spark plugs** for the Austin-Healey 100-6 and their **modern equivalents**:

 🔧 Factory-Recommended Spark Plugs (1956–1959)

- **Original specification**:  

  - *Champion UN12Y* or *Champion RN12YC*  

  - Copper-core, long-reach plugs with a projected nose  

- **Gap setting**:  

  - Typically **0.032" to 0.035"** for standard ignition systems

 🔁 Modern Equivalent Spark Plugs

| Brand     | Model         | Notes |

|-----------|---------------|-------|

| **NGK**   | BP6ES         | Most commonly used modern equivalent; reliable and widely available |

| **NGK**   | BPR6ES        | Same as BP6ES but with a resistor (for radio interference suppression) |

| **Champion** | RN12YC     | Direct modern replacement from the original manufacturer |

| **Bosch** | WR9DC         | Suitable alternative with similar heat range |

| **Autolite** | 935 or 945 | Compatible copper-core plugs with correct reach and heat range |

 ⚙️ Practical Tips

- **Avoid platinum or iridium plugs** unless using a high-energy ignition system — they may not perform optimally in classic engines

- **Stick with copper-core plugs** for best compatibility with original ignition setups

- **Check gap** before installation — even new plugs may need adjustment

- **Colder plugs** (e.g. NGK BP7ES or BP8ES) may be used in tuned or high-compression engines

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Tyres: Here’s a summary of the **factory-recommended tyres** for the Austin-Healey 100-6 and the most suitable **modern equivalents** available today:

 🏭 Factory-Recommended Tyres (1956–1959)

- **Original fitment**: 5.90 x 15 crossply tyres  

- **Typical brand**: Dunlop RS5  

- **Wheel size**: 15-inch rims, typically 4.5" wide  

- **Tyre type**: Bias-ply (crossply), tube-type  

- **Recommended pressures**: 25 PSI front / 30 PSI rear

🛞 Modern Radial Equivalents

| Tyre Model | Size | Notes |

|------------|------|-------|

| **Michelin XAS** | 180 HR 15 | Closest match in diameter and profile; excellent ride and handling |

| **Pirelli Cinturato CA67** | 165 HR 15 | Period-correct tread; narrower footprint, good for originality |

| **Avon CR6ZZ** | 185/70 VR 15 | Motorsport-focused; better grip but heavier steering and less period-correct |

| **Blockley Radial** | 165 VR 15 | Steel-belted classic tyre with authentic look and modern performance |

| **Vredestein Sprint Classic** | 165 R 15 | Affordable option with vintage styling and good road manners |

 ⚙️ Fitment & Practical Tips

- **Michelin XAS 180 HR 15** is widely regarded as the best all-round road tyre for the 100-6  

- **185/70 R15** tyres may require 5" or wider rims and can affect steering feel and ride height  

- **Inner tubes** are recommended for wire wheels — Michelin 15E is a common choice  

- **Avoid modern low-profile tyres** (e.g. 195/65 R15) — they compromise handling and aesthetics  

- **Crossply alternatives** like Avon Turbospeed 590 H 15 are still available for concours originality

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Racing

The **Austin Healey 100-6** did compete in racing events and had notable success. It was particularly prominent in **European rallies**, where it won its class in many competitions. The car's combination of performance, reliability, and agility made it a strong contender in various racing events.

One of the most famous events associated with the Austin Healey 100-6 is the **Rallye Monte Carlo**, where it has participated and performed well over the years. The car's performance in this event helped cement its reputation as a capable and competitive sports car.

ICONIC MOMENTS

The Austin Healey 100/6 has had several iconic moments in motorsport history. Here are a few highlights:

1. **1957 12 Hours of Sebring**: Three modified 100/6 cars were entered in this endurance race, featuring streamlined bodies and Weber carburettors. One of these cars finished second in its class, showcasing the model's potential.

2. **1958 SCCA Championship**: Corvette racer Dick Thompson drove a 100/6 to win the SCCA Championship, demonstrating the car's competitive edge in American club racing.

3. **Rally Success**: The 100/6 participated in various rally events, including the **Liège-Rome-Liège Rally**, the **Coupe des Alpes**, and the **Tulip Rally**. While it didn't secure outright victories, it often finished first or second in its class.

4. **RAC and Tulip Rally**: In the spring of 1958, Jack Sears and Peter Garnier drove a 100/6 in the RAC Rally and Tulip Rally, further cementing its reputation in rallying.

These moments highlight the Austin Healey 100/6's versatility and performance in different motorsport disciplines.

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Valuation

In 2025, the value of an **Austin Healey 100-6** in the UK can vary depending on its condition, mileage, and original features. Generally, you can expect it to be valued between **£35,000 and £50,000**. Well-maintained examples with low mileage and original parts tend to be on the higher end of the spectrum.

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Investment Assessment

Here’s a considered investment rating for the Austin-Healey 100-6 (1956–1959) based on historical data, market trends, and collector sentiment:

💰 Investment Rating: **3.5 out of 5**

📊 Rationale

- **✅ Moderate Appreciation**  

  - Median UK sale price: ~£31,625  

  - Top sales exceed £150,000 for concours or rare variants  

  - Values have risen steadily, especially for BN6 two-seaters

- **✅ Rarity & Enthusiast Demand**  

  - Only ~14,436 built; BN6 models are notably rarer  

  - Just 5 currently registered in the UK, enhancing exclusivity

- **⚖️ Market Position**  

  - Sits between the more affordable MGs and the pricier Healey 3000  

  - Less iconic than the 100 or 3000, which slightly tempers top-end growth

- **🔧 Ownership Costs & Support**  

  - Strong parts availability and club support  

  - Reasonable maintenance costs compared to Italian or German contemporaries

- **📉 Risks**  

  - Market can be sensitive to originality, provenance, and restoration quality  

  - Modified or non-matching cars may underperform

🧠 Summary

The 100-6 is a **solid mid-tier classic investment** — not a speculative rocket, but a dependable asset with charm, usability, and a loyal following. Its transitional status between the 100 and 3000 makes it historically significant, and well-kept examples are increasingly sought after.

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Clubs

There are **owners clubs** for **Austin Healey 100-6** enthusiasts in Northern Ireland! One notable club is the **Austin-Healey Club of Northern Ireland**, which organizes events, runs, and social gatherings for members. They provide a great platform for owners to connect, share knowledge, and enjoy their cars together.

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