Well SK, the thing is i am not looking for 20-30% gain, i am planning for at least 150kw at the rear wheels. Ambitious and crazy i know but done properly then everything runs fine.
A compound setup is very hard to build as to integrate two compressors is one hard job and the harder one is to find two which fit best. I am not that much versed on turbo's so i think i will stick to parallel turbo's (lay man's solution to power).
I am actually leaning more and more towards the T25's they are basically free and pack a punch plus they don't have an internal waste gate which is a huge edge while the CT26 has an internal waste gate at 8psi. I might be able to get 15psi and the optimum flow with the right piping and a intercooler. From what i anticipate they will start to spool up 1200-1300 rpm range and cut off at 3500-3600, Realistically, one has no need to rev up the whole range of diesel as gearing range is pretty less than that. I will have to up the anti a bit on the pump though.
Its all a theory at this moment until i do more research and more math. Technically the more boost the better the acceleration but how long you can hold that is upto flow.
Two T25's, external manually adjustable waste gate, manual boost controller, oil cooler and a inter cooler is what i need.