Recently I've purchased the Wren's MW54 turbine kit from JD Enterprises.
I was so disappointed of their poor workmanship.

1) The main shaft cover does not fit to diffuser: Bore diameter of diffuser is 20mm but shaft cover has 21mm.
2) NGV dia.(54mm only, not 55.2mm) for turbine wheel was not sufficient for turbine wheel(54.5 mm).
3) Fuel pipe assembly is also bad, so I have to order new one to Wren UK.
4) Vaporizer tubes are made from the stainless tubing, however, you have to chage it to inconel if you want to keep your turbine in long life, Wren UK sells now new MW54 mk2 which was replaced to inconel tubing.

I have to remodel it to make a good engine because they have a policy of no refund.

If you are interested in Wren's turbine, I recommend you to purchase it directly from Wren co. in UK, they have the better skill than JDE and are very kind to your inquiry.

Jae

Korea