A large part aluminium insert supports the part of the engine and creates adequate ac and adverts tightness. The very best insert may be used to enhance flex as required determined by each track. The inserts are connected with machined flanged threaded alu peanuts from top, so the carbon wont harm.
The framework with both inserts is about 60 grms lighter compared to the very same in aluminium.
Serpent metal loads may be always place the excess fat in preferred places.