I see that we used the same King bearings. How do you like them? The SI bearings
are different than traditional bi or tri metal bearings. Notes from my build sheets:
CP-Series, AM-Series & SI-Series Bearings:
King CP-Series, AM-Series & SI-Series bearings are recommended for OE applications. CP-Series bearings are copper-lead on steel (Tri-Metal) with a .001" copper-lead tin overplate. AM-Series bearings are aluminum-copper-tin plus Alloy on high-strength steel (Bi-Metal). SI-Series bearings are Silicon-Aluminum bearings (Bi-Metal) which are designed for Aftermarket Gasoline or Diesel Engine Rebuilding & Performance Engines with OE Crankshafts.
Main KING Silicon Alecular MB557SI .010
King Silicon Alecular Bearings:
The silicon particles help round off high spots on the crank surface during engine operation, which reduces friction & related wear. Because the bearings are unplated, wall variances are reduced by as much as 40% less than tri-metal (over-plated copper lead) bearings. KING's SI bearings easily exceed maximum peak load capacity for car and light duty applications. Minimized debris embedment, SI bearings are unplated and bored, hard-particle debris is instantly flushed through the bearing and filtered out of engine rather than scoring the crankshaft and causing long term damage.
Rod KING Silicon Alecular CR865AM .010 + .002 OD w/Housing Bore Resized .002" Larger Than Stock
from enginebuildermag.com: According to one crankshaft manufacturer, the first factor to be considered in choosing the correct engine bearings is the actual material the crankshaft is made of. The crankshaft manufacturer will provide you with reliable information as to which bearings they consider to be best suited for their product, and you should heed this information closely.
For high performance and mild race engines high quality, cast iron or steel alloy is a popular material. Due to its metallurgical composition, crankshaft suppliers often recommend using a classic bi-metal design bearing with any cast crankshaft. A forged or billet steel crankshaft considerably expands your choices for bearing designs.
Perhaps the best advice given here is again to check with the crankshaft supplier and choose main, thrust and rod bearings recommended by the crank and bearing manufacturers. It’s also imperative to carefully check that each bearing will clear the radius in the journals and still provide the right amount of clearance required for the application. Again, information you obtain from the crankshaft and bearing manufacturer should be your guide for bearing material and design, and recommended clearances.
