External
Wastegate is used to control /adjust Boost. Understand you got a good deal if you bought that downpipe and it's an external wastegated DP you will need the Deltagate because the DP will not work with the stock boost actuator. You have to use an external WG whether Turbonetic Delta or a Tial 38mm. Now if it's not external DP and is internal DP then the external gate does you no good. If the DP is external Use the EWG that come with it is it still connected to DP. For the most part when working correctly they control boost creep and seem to work better in general at higher boost levels...