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MK5 Platform EDC16 to MK4 Platform Engine conversion BLS / BXE / BKC / BJB to ASZ / ARL Conversion

MK5 Platform EDC16 to MK4 Platform Engine conversion BLS / BXE / BKC / BJB to ASZ / ARL Conversion

You may find yourself reading this because you are in the unfortunate position of having con-rod failure on a Mk5 Platform vehicle such as 1.9 Caddy BLS / 1.9 Golf BXE Engine. This issue is proving to be very common, we receive multiple phone calls and emails per day in relation to this.

Rather than replace the failed block with like for like we recommend installing the ASZ PD130 / ARL PD150 engine from MK4 platform

A quick glance on Ebay will show how overpriced BLS / BXE engines are due to the high demand. In comparison a PD130/150 engine can be picked up for as little as £150.

From a tuning perspective, there are very few, if any other companies that have pushed the PD engines to the limits we have. From experience the small journal bottom end on the BLS engine will not handle anywhere near the power / torque that the ASZ/ARL engines will.

The main differences between engines you will need to consider when carrying out this conversion are; (assuming you plan to keep all original wiring, clocks, ECU, etc. Have reasonable mechanical knowledge and are capable of sorting simple wiring and coolant pipe relocation's)

  • Crank Sensor
  • Cam pulley
  • Ancillaries / EGR

On to the conversion...

The Cranks Sensor

On the BLS engine this is located with the seal on the end of the crank (behind the flywheel) The MK4 ASZ/ARL Sensor is located in the block.

BLS Engine Conversion

ASZBLS Engine Conversion

This means you will need to purchase a new BLS Crank sensor pickup seal and modify the ASZ / ARL block to accept this.

NOTE: We strongly recommend not attempting to reuse your old seal, it’s not worth it. The only time you will find out is when the engine is in with gearbox installed and you have to remove the whole lot again to rectify it.

The modification is quite simple, you need to drill grind the block to allow clearance for the sensor.

BLS Engine Conversion

BLS Engine Conversion

BLS Engine Conversion

BLS Engine Conversion

Cam Pulley

Again this is a simple swap however without this the engine will not run correctly.

Swap the cam pulley from the BLS engine on to the ASZ/ARL engine.

We would recommend installing a new timing belt and waterpump at the same time. It’s also worth having a quick look at the camshaft for any signs of wear.


If you are carrying out a straight swap you will need to remove all ancillaries from the BLS engine and install on the ASZ/ARL engine.

To ensure the vehicle runs correctly don’t forget to swap the injectors. (it’s worth retaining the PD150 injectors incase you plan to upgrade in the future. If not drop us an email, we usually pay between £80-£120 for a used set of PD150 injectors).

If you are planning on upgrading at the same time as the engine conversion there are some things to consider before swapping to the PD130 / PD150 parts:

  • Turbo - If you are wanting to upgrade the turbo remember that the stock BLS turbo is top mounted with a 'push' vacuum actuator where as the PD150 Turbo is bottom mounted with a 'pull' vacuum actuator so this upgrade is not a direct swap.
    We do have direct replacement turbo upgrades available capable of 200 & 220bhp:
  • Injectors - The PD130 / PD150 injectors can be fitted as an upgrade with a max power rating to around 230bhp. If you are fitting the injectors at the same time as the conversion the vehicle will need to be tuned straight away other wise the engine will not run smoothly. We also do not advise installing the larger injectors with the stock PD105 turbocharger.


One other issue you will face is the lack of mounts for the original BLS EGR cooler. One way to overcome this is to remove the EGR system completely. Alternatively you will need to fabricate brackets.

If the above seems to much effort or out of your comfort zone, often have converted engines available, ready to swap:

19 10 2018

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