The RB25 NA should be as cheap as the RB20DET infact I suspect its even more cheaper..so I would say arounnd RM1500-RM2100 for the half cut. However, having to go through making new engine mountings , wiring and pipings...why isn't the RB25DET ( turbo version) an option? I mean the amount of work that needs to be done is quiet similar, so why not?
There's a white E36 running on a 600bhp RB26DETT in Kelantan so I suppose a RB25 is possible as it shares the same mountings as the RB26s.
Do E36 have 50/50 weight distribution?