The base STS C6 twin-turbo system is shown here. As we mentioned in our story, ECS uses different turbochargers and some other upgrades we'll discuss as we go along. If you're worried about larger turbos yielding turbo lag, fear not. All turbos used by STS and ECS are specifically sized to be rear-mounted and are internally quite different from your typical front-mount units. Thanks to this, boost response is said to rival that of an ordinary turbo system.