408ci LS Long Block for NA

Is your project ready for its new LS? Our standard build 408 puts out 720 hp naturally aspirated.  No supercharger or crazy cam needed. We get these results from our precision CNC machining, parts selection and tune. If you watch the videos in our YouTube Machining Playlist, you'll better understand how we put up such big numbers on this engine. The short block starts with a seasoned GM 6.0L block that we have digitally remastered to better than new condition. The mains are upgraded with either ARP or P1 main studs. The Callies 8-counterweight stroker crank gives us additional displacement, reduced harmonics and increased stiffness for longer life. The rotating assembly is completed with forged Callies Compstar Extreme rods and Diamond R Series pistons. We are exclusive with COMP Cams who makes all our custom grinds.  The valve train is stabilized with a COMP trunnion set.  That brings us to the cylinder heads. These AFR Mongoose LS3 heads have a 12-degree valve angle for improved per