Dart has just released a new cast-iron cylinder block that is designed for guys who want to build a Gen I—style small-block that can make 600 hp but are not interested in a full-tilt race block like the Little M. The Dart Special High Performance (SHP) block comes in either 4.00- (PN 31161111) or 4.125-inch (PN 31161211) bore diameters that can be drilled out to a maximum of 4.165 and still have 0.230-inch of thrust side wall thickness. These blocks all feature a priority main lubrication system, blind head bolt holes, and ductile iron four-bolt main caps with splayed outer 3/8-inch bolts. These blocks are two-piece rear main seal castings but incorporate all the factory locators that allow the use of an OE hydraulic roller camshaft, while still allowing the use of a more traditional flat-tappet camshaft. Price for this standard-deck block is $1,455.99 from Summit Racing. Dart is also going to build some 372ci and 400ci assembled short-blocks using this new SHP block. The 400 is rated at 525 hp at 6,000 when used with a 230-degrees-at-0.050 hydraulic roller cam, 200cc Iron Eagle or Pro 1 aluminum heads, and a 700-cfm carburetor.