I am wondering about what air filter arrangement and what it looks like.
I'd really like to reproduce the classic double K&N arrangement, but no info about whether that can be made to work.
Failing that is it Pipercross or ITG air filter and is it possible it as as simple as a deeper (higher) version of the standard Caterham part?
I would prefer to avoid having to engage in drilling etc.
Come to think of it is there a standard R400 air filter to fit on the existing base plate?
and in parts we have this: