While it's easy to get sucked into the fantasy world of factory parts, the one thing I always consider is, what happens when it wears out?
Where to source replacement parts once the unobtainium wears out or breaks.
Will an OEM or aftermarket part suffice or be compatible with the race component?
It's the one question that keeps me down to earth often when the fantasies start to creep in.
Ain't that the truth!!
Effectively you're only buying,at best,half an engine once you've found everything else at considerable cost also, someone who knows what they're doing has to assemble the thing and its good for how many hours run time?
Are you a race team with the backing of hrc and peripheral multi-national sponsors?
On a more realistic note a solid build using proven suppliers/builders around the globe for "reasonable" money can net you around the 150rwhp mark,which incidentally by all accounts is the upper limit of the stock transmission.
Not my research by the way, the words of individuals far more learned than myself.