It is machined from 300x100x20 slab of aluminium. There is provision for both Super Silencer mounting and tuned pipes (test stand can also be used for F2A tests). 

The stand will be bolted down to a Workmate with 4 off 6mm cap heads.

A good test stand is the starting point for repeatable engine testing.

https://cl-speed.bmfa.uk/wp-content/uploads/2024/01/Test-stand-flycutting.mp4

The parts are being made according to the excellent article that Peter Halman wrote in Aeromodeller  issue 1035

Back issue 1035 link

The Super Silencers are part way through manufacture, I am making a few for my friends as well, the turbo cone plug head are done and all of the fixtures for modifying the cylinder porting on the milling machine are manufactured and ready for use.

https://cl-speed.bmfa.uk/wp-content/uploads/2024/01/Irvine-12-conversion-parts-small.jpg

https://cl-speed.bmfa.uk/wp-content/uploads/2024/01/Irvine-12-cylinder-modifications-small.jpg

I will be flying in the 12 Open Class not 12 PRR