In the case of the SVO 460 block shown here, the No. 2 cam bearing spun so badly that it left scars in the cam bore greater than 0.005 inch deep. The snag is, after the cam bore is cleaned up on the line-boring machine, the outside diameter of the largest available repair bearing will be too small and will hopelessly rattle around loose in the block. If we had a magic wand, we could wave it over the Durabond catalog and make a larger 0.010 oversize repair bearing appear, but the wand is in the shop.
 As the cutter makes its way...  As the cutter makes its way from the front of the block to the back, it enlarges all five cam bores from a 2.250- to a 2.265-inch diameter. Even though the damage is confined to the No. 2 cam bore on this 460 block, cutting all five bores establishes perfect alignment. After cutting, a No. 4 FE cam bearing must be used in all five cam bore positions of the block. |  Compare this photo with the...  Compare this photo with the damaged bore to see the effect of 0.015-inch overbore. There is no way this problem could have been solved with the available 0.005-oversize repair bearing. | |
You don't have to buy five complete FE cam bearing sets to get the ones you need. Just score a Durabond PN FP-15-4T. It's a five-pack of standard-size No. 4 FE cam bearings. Remember to index the oil feed holes in the cam bores to the slots in the bearings before driving them home. If your block has even deeper cam bore damage than ours, know that the FE's No. 3 (2.280-inch), 2 (2.295-inch), and 1 (2.310-inch) cam bearings are progressively larger than the No. 4 bearing (2.265-inch) used in this story. So you have plenty of options for going oversize.>>>>>>
An expensive (i.e., extremely time consuming) solution is to align-bore the damaged cam bore oversize by about 0.100 inch and then machine up a steel sleeve that could be pressed into the block. Then a stock cam bearing could be installed inside the sleeve and everything would be good again. This course of action was being planned when Evans' Jaime Gonzalez did research and discovered the fact that a suitably sized cam bearing exists for the 385's Blue Oval cousin, the Ford FE big-block. At this point, it must be noted that the 460 big-block is fairly unique in its use of common-size 2.250-inch cam bore diameters in all five positions. The FE block-like most popular engine designs-has progressively sized cam bore diameters that get smaller as you move from the front of the block to the rear.
Knowing this, Gonzalez noticed that the FE's No. 4 cam bore takes a bearing that has an outside diameter of 2.265 inches (Durabond PN FP-15-4T), the right size to fit snugly in the 460's repaired cam bore after align-boring has removed the 0.005-inch-deep scars. The key element in this deal is the happy coincidence that the 460 and the FE both share common 2.124-inch cam journals, so the inside diameter of the FE cam bearings are a perfect match for the 460s. So thanks to some well-researched mixing and matching, the folks at Evans Speed have come up with a cost-effective solution for owners of Ford 385 big-blocks with damaged cam bores.