Video Twin Turbo LSX427 Steady State on Engine Dyno Advertisement ByEngine Builder on Mar 22, 2013 This short video shows a customers Twin Turbo charged LSX 427 being run on our engine dyno at steady state for testing. The turbo’s are 72mm. The engine is 4″ bore x 4.125 stroke using the LSX block.AdvertisementClick Here to Read MoreAdvertisement Advertisement In this article: The Importance of Block Resurfacing Understanding Bearing Clearances: Part 2 Understanding Bearing Clearances: Part 1 Video: The Advantages of ARMEX Advertisement VIDEOS Watch Engine Builder's latest discussions and explanations. SHOP Shop the latest Engine Builder merchandise. SUBSCRIBE Stay up to date by signing up for the Engine Builder newsletter.