Any oil grooves that are machined away during the process must be restored. The process begins by precisely align boring the cam bearing bores to the specified dimensions. Dart also has roller bearings for their own blocks fitted with 55mm camshafts (DRT32220042).Ī reputable, high performance engine shop is recommended for the necessary machining operations. (COM350RCB-KIT) that is engineered for small block Chevy and small block Chrysler 360 applications, while Ford Racing has kits for the small block 351 SVO (FRDM6261-D351) and big block 429-460 (FRDM6261-A460) engines. Several suppliers including Comp Cams, Dart, and Ford Racing offer specialized bearings for popular high-performance engines. of the cam lobes so that the camshaft may be installed into the block. A cam bearing set must be selected that is compatible with both the engine block and camshaft. A custom ground camshaft, or machining of the cam journals of an existing camshaft, may be required as well. Consulting with a trusted engine builder and reputable camshaft grinder prior to performing any machining operations is a necessity since the cam journals must be compatible with the I.D. Needle roller cam bearings can boost horsepower and improve reliability in high-performance engines.īearing installation is a bit involved and requires several important steps. Lastly, the free-rolling design of roller cam bearings reduces internal engine friction and oil temperatures. This benefit is two-fold, because oil draining from the cam bearings and falling directly onto the rotating assembly is eliminated, reducing oil aeration and windage losses which cost precious horsepower. Also, because needle roller cam bearings require only splash oiling and lack oil delivery holes, oil flow through the cam bearings is eliminated, improving flow to the main and rod bearings. One of the most important benefits is that the needle bearings can easily handle the extreme loads generated by high-pressure roller valve springs because of their increased load capacity. A steel billet camshaft is also required as a conventional cast flat-tappet camshaft is not compatible with the surface hardness of the needle roller bearings. That’s where needle roller cam bearings have consistently proven their value in high-performance engines.Īlthough the initial cost can exceed several hundred dollars, primarily due to added machine shop labor, needle roller cam bearings offer several important benefits that can help offset the expense. Traditional steel-backed lead Babbit cam bearings may be fine for most racing applications, but they are not well suited to the ultra-high valve spring loads common in maximum endurance racing and can only endure so much load before they ultimately fail. Steel-jacketed needle roller cam bearings can not only increase the durability of a high-end racing engine, but add a few horsepower as well.