Jaguar XJS V12 Manual Gearbox Conversion: The Ultimate Upgrade Enthusiasts Crave
The Jaguar XJS, a grand tourer renowned for its sleek lines and luxurious appointments, holds a special place in the hearts of classic car enthusiasts. While the V12 engine offered unparalleled smoothness and power, the automatic transmission often left drivers yearning for a more engaging driving experience. This is where the Jaguar XJS V12 manual gearbox conversion comes in, offering a transformative upgrade that elevates this iconic car to new heights of performance and driver involvement. This article delves into the reasons behind this popular conversion, the considerations involved, and why it’s considered the ultimate upgrade for XJS owners.
Why the Manual Conversion? Unleashing the Beast Within
The appeal of a manual transmission in the Jaguar XJS V12 is multi-faceted. While the original automatic provided a comfortable ride, it could feel somewhat disconnected from the raw power of the V12. The manual conversion addresses this in several key areas:
- Enhanced Driver Engagement: Rowing through the gears with a manual gearbox provides a more direct connection between the driver and the engine. This heightened level of control and feedback transforms the driving experience, making it more visceral and rewarding.
- Improved Performance: A manual transmission allows for more precise control over gear selection, enabling the driver to optimize engine speed and power delivery. This can result in quicker acceleration and improved handling.
- Increased Reliability (Potentially): While automatic transmissions are generally reliable, age and wear can lead to costly repairs. A well-maintained manual gearbox can often prove more durable and cost-effective in the long run.
- A More Sporting Aesthetic: The presence of a manual gearshift adds a touch of sportiness and classic appeal, further enhancing the XJS’s already impressive image.
- Increased Resale Value (Potentially): In a market that appreciates enthusiast modifications, a well-executed manual conversion can increase the car’s value and desirability.
The Conversion Process: What to Expect
Converting an XJS V12 to a manual gearbox is a complex undertaking that requires significant mechanical expertise and careful planning. The process typically involves the following key steps:
- Component Acquisition: Sourcing the necessary components is crucial. This includes:
- A suitable manual gearbox (often a Tremec or Getrag unit)
- A clutch assembly (clutch disc, pressure plate, and release bearing)
- A flywheel (designed to mate with the engine and clutch)
- A pedal box (with clutch and brake pedals)
- A hydraulic clutch system (master cylinder, slave cylinder, and lines)
- A gear shifter and linkage
- Custom driveshaft (to connect the gearbox to the rear axle)
- ECU Tuning (to account for the absence of the automatic transmission)
- Engine and Transmission Removal: The automatic transmission is removed, along with its associated components.
- Clutch and Flywheel Installation: The new flywheel and clutch assembly are installed on the engine.
- Gearbox Mounting: The manual gearbox is fitted to the engine, often requiring custom mounting brackets.
- Pedal Box and Clutch System Installation: The pedal box and hydraulic clutch system are installed, ensuring proper operation.
- Driveshaft Fabrication: A custom driveshaft is fabricated to connect the manual gearbox to the rear axle.
- Shifter Installation: The gear shifter and linkage are installed, providing the driver with control over gear selection.
- Wiring and ECU Tuning: The wiring harness is modified, and the ECU is reprogrammed to remove the automatic transmission functionality and optimize engine performance.
- Testing and Refinement: The car is thoroughly tested to ensure proper operation, smooth gear changes, and optimal performance. Adjustments may be necessary.
Key Considerations Before You Begin
Before embarking on a Jaguar XJS V12 manual gearbox conversion, it’s important to consider several factors:
- Budget: This is a significant investment. Factor in the cost of parts, labor (if you’re not doing the work yourself), and potential unexpected expenses.
- Mechanical Expertise: This is not a project for beginners. It requires a high level of mechanical knowledge and skill.
- Parts Availability: Sourcing the correct and compatible components can be challenging. Research and planning are essential.
- Professional Help: Consider hiring a reputable mechanic or specialist experienced in classic car conversions.
- Legal Requirements: Ensure the conversion complies with local regulations and emissions standards.
- Impact on Value: While the conversion can increase value, it’s essential to consider the long-term impact on the car’s originality and desirability.
The Rewards of the Conversion: A Driving Experience Transformed
The Jaguar XJS V12 manual gearbox conversion is more than just a modification; it’s a transformation. The resulting driving experience is significantly more engaging, responsive, and rewarding. The driver is now fully in control, able to harness the full potential of the V12 engine and experience the XJS in a whole new light. The conversion breathes new life into this classic grand tourer, making it a true driver’s car.
Conclusion: A Legacy of Performance and Passion
The Jaguar XJS V12 manual gearbox conversion is the ultimate upgrade for enthusiasts seeking a more visceral and engaging driving experience. While a complex and demanding undertaking, the rewards are undeniable. By embracing the manual gearbox, XJS owners can unlock the full potential of their cars, creating a driving experience that is both exhilarating and deeply satisfying. This conversion is a testament to the enduring appeal of classic cars and the passion that drives enthusiasts to enhance and personalize their prized possessions.
Frequently Asked Questions (FAQs)
1. What is the best gearbox to use for the conversion?
The most popular choices are Tremec and Getrag gearboxes. The specific model will depend on the power output of the engine and the desired driving characteristics. Research and consult with experienced mechanics to determine the best fit for your XJS.
2. How long does a manual gearbox conversion take?
The time required varies depending on the complexity of the conversion, the availability of parts, and the experience of the mechanic. It can range from several weeks to several months.
3. Will the conversion affect the car’s fuel economy?
Potentially. While a manual gearbox can allow for more efficient engine operation, the overall impact on fuel economy can vary depending on driving style and gear ratios.
4. Can I perform the conversion myself?
If you possess a high level of mechanical expertise, the necessary tools, and the time, you may be able to perform the conversion yourself. However, it is highly recommended to have a professional mechanic involved, at least for consultation and assistance.
5. Does the conversion require any body modifications?
Minor modifications may be required, such as adjustments to the transmission tunnel or the creation of custom mounting brackets. The extent of these modifications will depend on the specific gearbox and components used.
