one waits to long for decent books manuals tuts etc.....i am yet to see any thing worthwhile.....in one place ......conitec has made promises of a book for the new versions of the engine like a4 : no book a5: no book and a6: an yes you guessed it no book. hmmm a pattern is amerging .....the only book ever to be created for it by conitec was when a3 was around ....oh how time flies when your building engines for a living ....obviously manuals or books etc are not available to use the engine to its peak performance....as the old story goes if you dont provide knowledge to use the engine ...then why should i buy it!?