Porsche 911 Turbo Engine Purrs In New Teaser [Video] Porsche revealed its new 3.8 liter twin-turbo engine 911 Turbo model in a video and the beastly vehicle purrs as good as ever. The Stuttgart-based manufacturer touted the 911 Turbo S variant as well, which is an ever mightier powerhouse. by Horia Ungureanu