Certainly, the sounds, the silvery sheen, and probably fine particulate matter in the
oil is a pretty good indicator of one or more bearing failures, Joel. Here is something that might help going forward.
The pickup to bottom of pan clearance in some Ford crate engines has been more than commonly thought appropriate. A safe distance that will not choke off the pickup and also not reduce apparent pan capacity is anywhere between 0.300" and 0.375" clearance off the bottom of the pan.
The easiest way to measure this is with the engine on an engine stand. You use a hamburger-sized patty of children's clay and place it on the bottom of the pickup. Install the
oil pan with a gasket and cinch down the
oil pan bolts the way you would finish up an engine build. Now remove the pan bolts, lift off the pan, and Viola! You have an exact representation of the pan to pick up clearance across the entire pickup face.
Use an Exacto knife or a razor blade to cut through locations of interest to see and measure the clearance. Try to shoot for the 0.300" to 0.375" pickup clearance space.
When the clearance space increases above 0.375", you are effectively reducing the volume of oil in the pan and potentially uncovering the pickup during mild to spirited braking, acceleration, and cornering. A high pickup and a potentially low oil level are an accident waiting for a place to happen.
The other increased risk operating condition is sustained moderate to high rpm. When the engine operates in the ~4000 rpm range, several dynamics are in play that the engine does not see at lower engine speeds. After the oil pump has done its job and gotten the oil to the correct bearing surfaces, the oil has to find its way back to the pan to begin the process all over again.
Each engine has an oil drain back behavior unique to its engine family. In simple terms, it is the time it takes the oil to return to the pan, de-aerate, and get pumped back into the oil galleys. At first, it doesn't sound like a big deal, but as we delve into the process, there are some interesting discoveries to be made.
The first thing we frequently forget is how much oil is required to wet the inside of the engine. Not lubricate but wet. The wetting process is how a lot of the oil gets back to the pan, but before it gets to the pan, it has to wet the inside of the block and run down into the pan. It doesn't seem like much oil at first, but a good number for most engines is 1 quart, sometimes a bit more.
The next consideration is crankshaft (and connecting rod) windage. As the oil comes down the crankcase walls, it is whipped up by the crankshaft into a foam-like substance. To prevent this, you need to use a good windage tray that protects the oil in the sump from the rotating assembly's windage and skims as much oil off the rotating assembly as possible while the engine is running.
Racers talk about the horsepower lost by whipping the oil into a foam. For guys like us, who are already overpowered, the issue is adequate lubrication for engine longevity. Ideally, you want a full-length windage tray that runs the entire length of the oil pan. A half-length tray and a smooth bottom oil pan will recover oil where the tray exists and whip oil into a foam where it does not.
Some parts suppliers offer what they call crank scrapers. These fit between the pan gasket and the oil pan. The fitment can be very close (0.030" sometimes less) to the crankshaft counterweights on both sides of the crankcase. They do exactly what their name implies. Here are two pics of a scraper and windage tray assembly from Improved Racing (the same guys that make those elegant oil T-Stats).
This is a pic of a windage tray and crank scraper installed on a darkside engine;
This is a pic of the windage tray and crank scraper before installation, viewed from the crank's perspective;
Sometimes you can find commercially available units for sale. You can also make your own with some cardboard, a pencil, and a box cutter when you can’t. It is not that difficult.
When you are done with the cardboard, go over to your PC, bring up the 2D/3D drawing program you downloaded from the internet, and make a drawing to take to your local water jet shop. He can easily cut out the crank scraper from flat stock for you. The same story with the windage tray, but use a sheet metal shop to do the fabrication for the windage tray. Consider how you will fasten the two together for your particular application.
The following comments would not apply to anyone who is scratch building a Lambo Miura, but — for everyone else, if this process is too much work, there is an alternative. You can put 2.92 gears in the rear end, run a 295x65x15 rear tire, and use a 5-Speed with a 0.64 OD, you will be able to cruise the expressways at 70 mph and 1500 rpm according to the
Second Strike Gearing Calculator — assuming you have a cam that allows your engine to operate at that rpm.