If you're diving into the world of high-performance engines, you know how crucial it is to have the right bearings in place. That's where the ACL Race Series Engine Bearings come into play. These aren't just any bearings; they're crafted with a unique blend of design, metallurgy, and engineering that really delivers when you're pushing your engine to its limits. Whether you're revving up a 4, 6, or 8-cylinder setup, these bearings are built to handle the heat—literally and figuratively.

One of the standout features is the high-strength overlay plate. It's thinner than what you might find in standard bearings, which means better fatigue properties. That’s a big deal when you’re talking about high RPM conditions. And let’s not overlook the hardened steel backs on all the rod bearings. They provide solid support for the bearing lining, making sure everything stays put even when the engine is screaming.

These bearings also come with increased crush, which enhances retention. No one wants to deal with bearings that shift under pressure. Plus, they’ve eliminated flash plating on the backs, allowing for better heat transfer and a tighter grip in the housing—this is what you want when you’re looking for reliability at high speeds.

Another cool feature is the increased eccentricity. This helps counteract any bore distortion you might experience at high RPMs, and it aids in forming those all-important hydrodynamic oil films. And if you’re worried about oil flow, the 3/4 grooved main bearings optimize the load-carrying surface area, ensuring that oil gets to the conrod bearings just the way it should.

When it comes to precision, these bearings don’t skimp. They maintain tight, consistent wall tolerances, so you can keep your clearances just right. Plus, they’ve got enlarged ID chamfers on the edges to fit those larger fillet radii you find on performance crankshafts. It’s all about making sure everything fits together seamlessly.

Now, let’s get into some specifics. You can grab these bearings in sizes like STD, .025, and .25. The oil clearance is standard, and they come as identical halves, which simplifies installation. Made from tri-metal with hardened steel backs, they’re designed to last. The dimensions are spot on—min shaft size is 1.888 inches, max is 1.8887 inches, and the tunnel sizes range from 2.0079 to 2.0084 inches. The maximum wall at the crown is 0.0592 inches, and the overall length is 0.673 inches.

For those working with a Nissan SR20DE/DET engine (that’s the 2.0L powerhouse), the 4B2960H-.25 set is your go-to for a 0.25mm oversized high-performance rod bearing set, measuring 17mm wide. Trust me, when you’re pushing your engine, you’ll want these bearings in your corner.