if anything the s14 has more egr stuff than s13. the s13 has egr, scv (swirl control butterfly valves), and a charcoal canister. the s14 has no scv, but it has an electronic evap system, which has like 4-5 more sensors and solenoids than a simple charcoal can setup (it regulates the charcoal can/evap rather than just having a can). not that any of that stuff is needed anyways