The side loading imposed by the rocker arms on the Ford 1600 Kent engine, especially in Formula Ford trim, takes a toll on the valve guides and can eventually lead to poor valve sealing, or worse. Engine builders recommend replacing valve guides in the Formula Ford engine when valve stem clearance exceeds 0.003".
Beware of using "universal" replacement valve guides! Ford used a small-diameter valve stem on the Kent engine. Universal guides typically fit valves with a larger stem OD and will have excessive clearance even when new. Our guides are designed specifically for Ford 1600 valve stems. They are supplied slightly undersized to allow reaming to the proper finished size.
Note: Ford originally cast the valve guides into the cylinder head. If your head has never had the valve guides replaced, you will need to remove the original guides by machining them out. Replacement guides can be pressed out.