Why does the RB26DETT sound nothing like BMW's N54 (x35i) engine? Both are twin turbo I6's with a 1-5-3-6-2-4 firing order.

The rb26 has 400cc less than the n54 and much less compression ratio and i guess the cams, head design and manifold design plays a big role too in the sound. Also the n54 has direct fuel injection and it must have a much more efficient combustion.