Valve Guide Drill for Classic Ferraris (AV1504, 95971504)

When rebuilding cylinder heads on classic Ferraris, one of the most difficult tasks will be replacement of the valve guides (e.g. 117563, 117565). The factory workshop manual suggests a hammer and punch (e.g. Tool AV1504, 95971504) to remove the guides. Removing guides in this fashion almost guarantees galling of the cylinder head which can lead to an imperfect guide seal. When this occurs the engine may draw oil or unmetered air past the guide.

This special piloted drill bit ensures this does not occur by instead removing the majority of the old guide with room for error. A thin shell remains of the old guide that can be broken in two or slid out. No cut is made to the cylinder head. This operation can be performed with a standard drill press or even a hand drill.

F355 drill bits are special order items and have an increased lead time.