Look no further. Here at Thomas Performance we have a range of performance products suitable for your TD5 Defender. With the right mapping & mods your TD5 can see 200bhp+. First and foremost you'll need to get yourself a Turbo Technics VGT turbo. A Variable Geometry Turbocharger acts like a small turbo initially then alters geometry to increase flow in higher revs, giving an improved spread of power across the rev range. TD5 VGT units use a special actuator operated by boost pressure to control the vane angle reducing lag and improving power throughout the rev range.
You must also fit an uprated intercooler to (see product listing here) to gain the best performance when paired with the VGT turbo and you will also require sufficient exhaust performance mods. See our listings for exhaust systems for your Land Rover TD5 (Defender 90 & 110). A turbo boost box is supplied with the turbo free of charge.