Standard crankshafts correspond to the original crankshaft, the ABE (General Operating Permit) remains valid. Sport crankshafts are not StVZO approved! Sport crankshafts sometimes have polished connecting rods, the modified crankshaft webs (full circle webs) result in increased pre-compression and better gas flow. The resulting higher speeds lead to improved starting behavior and better overall performance. Recommended in conjunction with tuning cylinders. Article Type Crankshaft Features Standard