This quality cam gear is an excellent choice for mild or mid-performance engines where a racing or performance camshaft is needed.  The helical design and aluminum material is similar to stock, so it will work with the stock crankshaft gear, yet still remain very quiet when the engine is running.  TIP: Aftermarket camshafts are all ground to use this "flat cam gear" design, so an early "Flat cam" oil pump will be required when using and aftermarket racing style camshaft.  Cam bolts are required.  Norris cams come with bolts already.  Most other manufacturers require purchasing the bolts seperately.