Hi Ian, Thanks......

Started building professionally over the winter as my full time job is very part time for that half of the year. Pretty much exclusively jets although I've just finished a 150cc Extra. The only down side to it is I've become even more anal about the details than I already was, just want to give the best model possible to the customer.

To answer your question................JetCat recommend a distance of 3/4 inch between the engine tail cone to tailpipe bell mouth. I used this distance coupled with the length of pipe to position the turbine, I didn't want the pipe poking out the back, luckily this put the turbine at the front most position helping with the CG. Had to heat proof the back end as the pipe sits a little inside the fuz just at the top.

Hope the FE L39 build goes well.

Cheers, Alex