You need the HKS VPC to run with the HKS dual intake system. because the HKS system dont have the air mess sensor anymore. the VPC conver it to pressure sensor type. so it will get more air flow then the JWT dual pop. but you must to have the VPC to run with the HKS dual intake. and you dont have to get the ECU upgrade to run with it. but the VPC cost much more then the ECU,and the dual intake is cust more also....