Ford on a stretcher? Bring it back to life and deny the smelter one more vintage block.
We love hearing from machine shops that discover novel solutions to sticky problems. One of the most imaginative is Evans Speed in South El Monte, California. The company has come up with a cool repair for Ford 385-series (429 /460/514) blocks suffering from spun cam bearings that involves a dip into the neighboring Ford FE big-block parts bin.
Typically, a cam bearing spins due to inadequate lubrication, improper bearing clearances, cam tunnel misalignment, or a bent camshaft. When disaster strikes and the cam and bearing stick together, the bearing insert spins with the cam and the resulting friction removes material from the cam housing in the block. This increases the diameter of the afflicted cam bores and leaves a rough surface in its wake. The traditional solution is to cut the cam bores oversize using a line-boring machine and install matching oversize bearings. Repair bearings are available for most common applications and feature larger outside diameters so they have the correct press fit in the block's cam bores after they are machined. These bearings feature stock inside-diameter measurements to suit the stock cam journals.
But there's a problem when it comes to the Ford 385-series engine family: The stock cam bearings all share an outside diameter of 2.250 inches, and the largest available repair bearing is only 0.005 inch oversize (Durabond PN FP-30R). What are you supposed to do if the damage to the cam bore goes deeper-as it often does?
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.
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.
