With more ZZZ through ZZ4 crate engines sold over the years than any other high performance crate engine, it only makes sense that GMPP would continue to improve that successful family of engines. Details: With more ZZZ through ZZ4 crate engines sold over the years than any other high performance crate engine, it only makes sense that GMPP would continue to improve that successful family of engines. The new Fast Burn uses the proven ZZ4 shortblock and ads to it the Fast Burn cylinder heads for 385 value packed horsepower. With value in mind, the Fast Burn uses stamped rocker arms and the same ZZ4 camshaft that powers thousands of hot rods. The Fast Burn is an excellent choice for the basis of a custom engine. Its strong forged steel crankshaft and forged powdered metal connecting rods have been proven to 500 horsepower. And its Fast Burn cylinder heads are hungry for a little more camshaft, approximately 425 horsepower at 6000 rpm is achievable by adding the HOT cam and 1.6 self aligning rocker arms. Value priced small-block power, great durability, easy power upgrades. It?s all that and more from the "More Than Just Power" people at GMPP. Fast Burn 385 Technical Information Horsepower 385 @ 5200 RPM Torque 385 @ 4000 RPM Max. Recommended RPM 5800 Compression Ratio 9.6:1 Block 10105123 Four bolt main, cast iron Crankshaft 12556307 Connecting Rods 10108688 PM rods Pistons 10159436 High silicon aluminum with offset pins Piston Rings 12528817 Camshaft 10185071 Hydraulic Roller Lift .474/.510" Duration @.050, 2.08/.221 Intake Manifold 12366573 Aluminum dual plane, no EGR 12496820 Aluminum dual plane, w/EGR and dual carburetor pad Cylinder Heads 12464298 Includes valves and springs Intake Valves 12555331 2.00" Exhaust Valves 12551313 1.55" Valve Springs 12551483 Rocker Arms 10089648 Steel 1.5 Valve Lash Zero Spark Plugs MR 43LTS Gap @ .045 Fuel 92 Octane Ignition Timing 32º total @ 4000 RPM with vacuum advance disconnected