1998 Defender 90

About

This build started with a solid base — a freshly rebuilt 300Tdi Defender on a galvanised chassis. But our customer wanted more than just a tidy restoration. They wanted real power, smooth driving, and the ability to keep up with today’s traffic. So we gave this Defender a serious upgrade, turning it into a high-performance daily driver that still holds on to its iconic character.

How it started

When the vehicle first arrived at our workshop, it was a standard 300Tdi Land Rover Defender fitted with an R380 gearbox. It had recently undergone a rebuild, including a brand-new galvanised chassis.

Our customer was looking for a significant upgrade-something far more refined and capable of keeping pace with modern motorway traffic.

To meet those expectations, we chose to install an M57N engine sourced from a BMW E53 X5, paired with an 8-speed automatic gearbox for improved drivability and performance.

Engine Servicing

Before going in, the engine received all the essential maintenance to ensure long-term reliability — a new timing chain, fresh seals, and gaskets throughout. But reliability was just the starting point. To really bring this build to life, we focused on extracting serious performance. We upgraded to performance valve springs, fitted a hybrid turbocharger for faster spool and greater top-end power, and finished it off with a custom ECU map tailored to the setup. The result is a smooth, powerful powerplant delivering around 400 horsepower — a huge leap from stock, and a perfect match for modern-day driving demands.

Gearbox Spec

To make the most of the new engine’s performance and improve overall drivability, we specced the Defender with an 8-speed automatic gearbox. This setup offers smooth, quick shifts and keeps the engine in its power band across a wide range of speeds- ideal for both motorway cruising and off-road control.

Compared to older transmissions, the 8-speed adds refinement, better fuel efficiency, and a far more modern driving feel, perfectly complementing the upgraded powertrain.

Integrating the gearbox is dead easy these days. On the electronic side, we used a standalone transmission control unit — the CANTCU — to manage shift logic and ensure seamless communication between the BMW engine and gearbox. This setup gave us full control over shift points and behaviour, allowing us to fine-tune the driving experience.

It took time to get everything just right, but the end result is a drivetrain that feels as if it rolled out of the factory that way.

Extras

Because this build was pushing the limits of what the M57 can deliver, we made sure to keep engine temperatures under control. An external engine oil cooler was fitted, along with a larger aluminium radiator from House of Torque — ideal for keeping things cool when it’s going head-to-head with Golf Rs off the lights.

Beyond the performance upgrades, the customer also wanted a few modern touches to finish things off. We fitted panoramic rear windows to let in more light, Apple CarPlay for seamless connectivity, a reversing camera for added convenience, and a Thatcham-approved alarm and tracker system to keep it all safe. A perfect mix of power, comfort, and peace of mind.