R&R Aluminum Rods
R&R has manufactured thousands of sets of connecting rods for hundreds of different engines over the years. That includes aluminum rods for Ford, Chevy, BMW, Mercedes, Jaguar, Aston Martin, Honda, Mazda, Mitsubishi, Subaru, Nissan, Kia, Hyundai, Toyota, Volkswagen, Porsche, as well as for numerous motorcycle, diesel, exotic, and vintage motors.
R&R’s billet aluminum connecting rods, the alloy is pre-stress relieved, allowing for a more stable rod, at least dimensionally speaking. Extrusions are kept on hand in varying thicknesses in standard lengths, usually 10 to 12 feet, then cut to rough length for machining. With this process, any rod imaginable can be made. If the correct thickness is not available, it can be ordered from their aluminum supplier in as little as 2-3 weeks. In as little as a single day, a raw extrusion can be transformed into a set of billet rods through a multiple step process where the extrusion is cut, faced, serrated, drilled and tapped, then machined into what will become the final product, a custom billet aluminum connecting rod. Rods are then fitted with the proper ARP rod bolts then sent down the line for final honing and pin fitting. Most of the process is the same with a forged rod, but once again, it’s the machining that is different in that it just takes longer. With improvements in machining capabilities with faster, more rigid machining centers, this time is minimized. With these capabilities, any connecting rod can now be custom, at little or no cost over a forged rod that is limited in what applications they are available for. These same processes apply to steel and titanium connecting rods, as there are manufacturers that use both processes with equal results.
Now that the flexibility of the true billet process utilizing extrusions is explained, you can see why we prefer the process, which allows us to make almost any connecting rod. When it comes to what is typically considered a standard connecting rod, like a domestic small block Chevrolet or import Mitsubishi connecting rod, where some companies make them and stock them in standard configurations, which allows for same day shipping in the best case scenario, you get a generic rod, designed to do everything ok, but excel at not one thing. Each application has a different set of requirements, whether they are for added strength, weight, or even as simple as clearancing for fitment purposes. When you order an R&R Pro billet aluminum or R&R Pro billet steel connecting rod, before it’s even started, there’s a list of details that are poured over to ensure that the rod that is machined fits your needs precisely- that’s why we give you a choice of alloys, bolts, and machining options to suit your application and it’s exact requirements. Whether you order four, six, eight or two hundred connecting rods, each piece gets meticulously examined and strict quality control ensures that the first rod is the same as the last. So why are aluminum connecting rods the preferred choice for those running high RPMs, lots of boost, or making huge horsepower? Well, the answer is quite simple. Think of the connecting rod as a spring or shock absorber. It cushions the inherently rough nature of combustion and acts like a buffer between your more expensive pistons and crankshaft. In these applications, a steel rod is too rigid and is more like a sledge-hammer than shock absorber, often leading to damage to the crank and the rest of your engine due to failure of the rod itself or a part connected to it. Some manufacturers claim their rods are street-able and can outlive a steel rod. We’d be lying if we made the same claim. An aluminum connecting rod is a spring and there is only an X number of times a spring will compress and return to it’s rest state without deformation. Deformation in our case is a rod failure, as with any connecting rod. Aluminum has a fixed fatigue life, just like that of a titanium connecting rod. Well, what’s that you might ask? Every material can be deformed to a certain extent and only a certain number of times before it breaks. Think of a crushed soda can. You can bend it forwards and backwards in the middle a few times before it will split open or tear in half. It’s the same thing with a connecting rod. Depending on the material and the application, a steel connecting rod might last almost forever or an aluminum connecting rod may last just a handful of passes (if you are really making LOTS of horsepower with boost and nitrous at high rpms with a very heavy piston). It’s hard to say with an aluminum rod what is the useable life. Controlled deformation and its performance as a spring and shock absorber is the reason people seek an aluminum connecting rod. If its weight reduction that is needed with the strength and longevity of steel, say longevity of an OEM part, it’s a titanium connecting rod you need. But the price you pay is its extreme cost. The old axiom pick two holds true: price, strength, reliability- you can’t have all three.
Some racers change their aluminum connecting rods religiously every few runs or every season, since typically the cost of a set of rods is less than the cost of the rest of the parts in a race engine. Import racers whose cars double both as daily drivers and weekend warriors typically use their rods for 10 to 15 thousand miles and again, change them just as a precautionary measure depending on how hard they run their engines. We’ve even seen customers put hundreds upon hundreds of passes on their aluminum connecting rods without failures. Like we already said, we can’t guarantee how long an aluminum connecting rod will last but we do take the time and make the effort to build the best connecting rod possible, and do it affordably.