Best engine to use in my opinion is the 218bhp iron-block M57, found in the 2004–2006 BMW E60 530d and X5 3.0d. The iron block is strong, proven, and takes tuning well.

For a base-spec build: 

• Wide-block M57 to MT82 gearbox adaptor 

• DDE5 wiring loom (2-plug ECU) 

• Custom engine mounts 

• Custom clutch friction plate with a 330d pressure plate 

• Stock BMW E46 5-speed flywheel 

• M57 inline fuel pump 

• Custom power steering pipes 

The BMW ECU needs programming: immo off so the engine will run in the Transit, and from there you’ve got stage 1/2 remap options and a dash controller. 

You can use the standard Transit radiator and intercooler for base-spec builds. You just need to make your own coolant pipework — I use a mix of original BMW and Ford coolant hoses and adapt them to suit. 

I use the BMW cat/DPF and adapt it to the original Ford exhaust — cut and weld the Ford system to the BMW. Keeping the cat/DPF also keeps you the right side of emissions rules. 

Yes — that’s the base-spec breakdown, and there are upgrades on top, like a better clutch/flywheel setup for higher-power builds. 

If you swap the engine, tell the DVLA (the V5C needs updating with the new engine number and capacity) and tell your insurer — an undeclared engine swap can invalidate your cover. 

This is general advice, not a step-by-step guide — every van and engine is a bit different. If you need any further specific advice, head to the ‘Ask Fletch’ page. And if you’d rather not do it yourself, this is exactly what I do day in, day out — get in touch.