The Nissan GT-R VR38DETT engine is our favorite platform here at Synergy Engines. All VR blocks are re-sleeved with LA Sleeve Race Sleeves.  We also offer Fire Ring and Receiver Grooves installed with the sleeves for a extremely strong block. If you are interested in CNC Porting and other mods we have plenty of options.  We do require a core for the project.   With different block options, strokes, and rod length options, there are many ways to get creative with the VR platform.  All of our builds are machined to the highest quality with no corners cut.