what? You said you wanted a recommendation.
Just replace the mufflers. The V8 doesn't gain much power so pick a sound on youtube you enjoy the most.
Daytona Blue 350Z (VQ-35DERevup)
Imperial Blue Trailblazer SS (LS2)
Royal Jade Pearl SC300 (2JZ-GE+W58 --> 1JZ-GTE+R154)
CT12A twin turbo @23psi (gone)
TO4S 60-1 P-trim T4 .70A/R @ 21psi (gone)
BW S366 T4 .91A/R @26psi
AEMv2/BC272/SP-QSV/Kaaz SQ-LSD/LQ9coils/water-meth/4"single/S366/T51R compressor cover--- build in progress