The red is because its accelerating and its almost dark. The camera makes it look like its glowing hot though! You dont see it in normal daylight? EGT is about 650 at full power. I already have a 14 blade compressor (I think?).

I have lots of bits laying about. Including a kamps and an old Shreckling built ten years ago and jj bits etc.

Early JJ motors were sort of good home built motors that needed some fine tuning and setting up.

As for upgrading with wren bits, why not? I had them! They fit, and they help. Its all just bits of metal at the end of the day. The tailpipe was swapped because the JJ one was too tight and hard to remove after a run or two. And because it ran a bit hot with the single bit jj one and the wren one was bigger area outlet after I cut 3mm off it for yet another home built mw54. The FOD screen front end was because I watched a huge bee go in at about 1/3rd power in my garden... Motor never even coughed though.