Originally posted by peter2.slow

Originally posted by Scandelous Tell us what the set up is first.

t3/t4 .57 trim .50 A/R T-25 wastegate @ 11psi 12x24x3.5 FMIC 2.5'' IC piping 1g BOV 360 4g63 injectors 4g63 Fuel pressure regulator 1:1 walbro 255 fuel pump arp head studs 3'' turbo back exhaust 2.5'' Down pipe S-AFC to fine tune

Just to clarify, how do you have a 2.5" downpipe but a 3" turboback?