Push your muscle car to the limit, and sooner or later you may run into some oiling issues. Since we've already covered basic oil system tech in the past, we decided to focus our efforts on hard-core racing applications this time around. So if you've ever cracked a cast oil pump from repeated wheelstands, sucked a pan dry while barreling down the corkscrew at Laguna Seca, or can't keep oil from whipping around the crank in your 8,500-rpm small-block, then this story's for you. For expert guidance, we sought out the advice of Thor Schroeder of Moroso, Mike Zeranski Jr. of Canton Racing Products, and Bob Sanders of Titan Speed Engineering. Now get schooled and stay lubed.
Thor Schroeder: "Maintaining oil control can be a challenge in road race vehicles that see constantly changing cornering loads. Moroso's road race oil pans feature sumps shaped like an upside down 'T.' This shape serves many purposes. One benefit is that it allows for extra oil capacity without reducing ground clearance. This is important since road race and autocross cars are often lower to the ground for handling and braking purposes. Likewise, proper road race oil pans must have trap door baffling, which are hinged pieces of sheetmetal that open up to a 45-degree angle during acceleration, cornering, and in some cases braking. The trap door baffles are attached to sheetmetal dividers, so during hard acceleration a trap door baffle will swing open and release a pocket of oil that has been held back by the divider. The released oil then feeds the oil pump pickup and keeps it submerged the entire time. The sides of the sumps that tee out are called wings, which hold pockets of oil that are held by trap door baffling integrated into each side. When a car takes hard right or left turn, the trap door on the opposite side opens up and releases oil to feed the oil pump pickup. When the trap door closes, the reserve of oil builds back up in order to be ready for the next time that it's needed. In the coming months, we will be expanding our line of multi-baffled road race oil pans."
Mike Zeranski Jr.: "Canton's road race oil pans are designed to provide the oil control necessary to maintain oil pressure and reduce horsepower loss, and are available for a wide range of popular chassis configurations. Deep-sump and T-sump designs extend the oil pan sump deeper or to the sides. This expands the oil pan's capacity while still providing clearance for the crossmember, steering components, and exhaust system. This extra capacity helps prevent oil starvation by providing additional oil to feed the demands of a high-performance engine. To control that oil and keep it directed to the oil pump pickup, we use baffling systems designed to work with the oil pan sump design. Our baffle systems use a combination of precisely positioned oil runners, one-way trap door baffles, and slosh baffles. Oil runners bring oil moving across the bottom of the pan toward the opening in the trap door baffle. The trap door baffle opens to allow oil into the compartment around the oil pickup, then shuts to prevent oil from moving away. The slosh baffle keeps the oil in the sump from splashing up away from the pickup. This not only keeps oil close to the pickup for scavenging, but keeps it from splashing into the rotating crank and absorbing horsepower."
Thor Schroeder: "Moroso oil accumulators are hydraulic cylinders with billet aluminum end caps that store oil under pressure, providing an instantaneous supply of oil and releasing it to the oil system when the pressure drops below a safe level. An accumulator can be tapped to the pressure side of the engine's oiling system, or tee'd into the return line of an oil cooler. We offer sandwich adapters that mount between the block and oil filter to make this easy. When the engine is running, oil pressure forces reserve oil into the accumulator and compresses the air ahead. If the engine's oil pressure should suddenly drop because of hard acceleration, severe cornering, or hard braking the air pressure immediately sends oil to the main galleys. When the danger is over and the oil pump is once again primed with oil, the pressure forces oil back into the accumulator where it is ready for the next emergency. Moroso offers different sizes of accumulators and valving options to meet the racer's needs. For an accumulator to function properly it needs a valve assembly. The valve has to be manually opened by hand before starting the car to pre-lube the engine and manually closed before turning the engine off. As an option, Moroso offers solenoid pressure valve kits in different oil pressure ranges.
"While many people associate accumulators with road race applications, Moroso sells more of them to drag racers than any other market. For drag racing, an accumulator is beneficial for pre-lubing the engine before start-up. Independent tests have shown that on street cars, over 85 percent of engine wear is caused by starting an engine. During hard acceleration, an accumulator would be beneficial in guarding against oil pressure fluctuations and during shut down, braking, and sudden deceleration. Drag racers have also used accumulators to free up horsepower by running less oil in the oil pan or using accumulators in classes that have oil pan limitations."
Mike Zeranski Jr.: "Canton's Accusump oil accumulator system provides engine pre-oiling and protection against oil pressure surges by accumulating oil from the engine then discharging it back when needed, and doesn't requires a separate pump to fill it with oil. Instead, the Accusump system uses your engine's own oil pressure to fill and naturally discharges back when that oil pressure drops. Engine pre-oiling is easily achieved by closing the Accusump valve just before engine shuts down and opening it back up to release oil just before the next start-up. Available in four sizes and with six different valve options, the Accusump system can be tailored to meet your exact needs. Built to withstand years of hard racing, its main body is built from an aluminum hydraulic cylinder that features a double-sealed billet aluminum piston to separate the air and oil inside the Accusump. In addition, it features thread-on billet aluminum end caps for added strength, a Schrader valve for adjusting the air pre-charge, a 160-psi air gauge, and a safety release valve to protect against extreme unit pressure.
"With all these features the Accusump works great in a variety of applications. It protects against oil starvation in road racing where hard braking zones and long, high-g turns are the norm. In drag racing applications, it keeps oil pressure up when cars are decelerating at the end of their run. If you have a hot rod that sits for a long time between start-ups, the Accusump provides easy pre-oiling to protect against dry start damage. The Accusump extends the capabilities of a wet-sump oiling system and pushes back the point where a dry-sump system is necessary. Many of our customers see the Accusump as an alternative to converting to a dry-sump system. In most cases, the Accusump can bridge the gap between a wet-sump system's performance and what is needed to go racing. Due to the significant cost difference, stepping up to a dry-sump system is usually only done after significant alterations in the chassis and engine have improved the car's speed and handling to the point where the use of a wet-sump system is impractical."
Mike Zeranski Jr.: "Under high cornering loads, oil can sometimes shoot out of the valve cover breathers. That's because when oil is hot, it can flow like water. The best defense against this is having the breathers positioned away from the direct flow of oil slosh. In circle track applications, we put the breathers on the left side of the motor and run a right-side valve cover with no vents. For applications were oil slosh moves in every direction, a baffle will help dampen this effect. A baffle can be installed directly into the valve cover, or a baffled breather grommet can be used. The best solution to prevent oil from reaching your breather is to run a line from the valve covers to a separate breather catch tank. In this situation, any oil that does make its way out of the valve cover will be collected in the tank. In some classes of racing, this type of setup is mandatory if the valve covers are going to be vented."
Thor Schroeder: "In recent years the term windage tray has been broadened to represent a couple different features. Often, the sheetmetal plate that goes over the opening of the sump, where it meets the body of the oil pan, is called a windage tray. This is actually the anti-slosh baffle, which is important in keeping the oil contained in the sump so that it doesn't get back into the rotating assembly. The windage tray itself is the screened or louvered piece that is either mounted directly to the main caps or in the oil pan itself, and it usually has an integrated crank scraper. At Moroso, our oil pan and windage tray designs live and die by our in-house dyno, outside testing by Moroso, our network of top engine builders, and the racers that test our products. We feel windage trays are important in a proper high-performance oiling system. The effects of a windage tray are more evident in some engines than in others. Static, short-stroke engines with big box oil pans that turn less than 5,500 rpm aren't going to be affected as much by a windage tray compared to an engine that is put through acceleration, deceleration, cornering loads, and quick up and down movements. Likewise, long-stroke engines with confined oil pans that turn over 5,500 rpm will experience more windage. We have seen and heard of windage trays freeing up to 5 percent more horsepower. Windage trays can also help control oil temperature and pressure by keeping oil off the crank so that it does not froth the oil, and put extra heat into the oil."
Mike Zeranski Jr.: "Windage trays work great in providing a few more easy horsepower when installing a high-performance oil pan. Canton designs its trays to complement our pans and the engines they are designed for. They help pull away oil spinning around the rotating assembly and keep oil in the pan from splashing up into the crank. In both cases they help free up the rotating assembly from the drag created by oil mist. Whether or not you think the hp gain is worth it depends on what you are trying to accomplish. When you're looking to squeeze every bit of horsepower from an engine, a windage tray is an important piece of the puzzle. They can often provide that little extra that is needed for an engine builder to reach a certain horsepower goal on the dyno. Of course, for street cars and other more recreational applications, the extra horsepower that the windage tray provides will not be noticed from behind the wheel."
Thor Schroeder: "A dry-sump oiling system consists of the dry-sump pump itself, which can have anywhere from one to six stages. The stage designation refers to how many scavenge and pressure sections the pump has. A single-stage oil pump has one scavenge stage and no pressure stages. The oil pan would have one externally exiting oil pump pickup and the oil pump would be outside of the oil pan and driven off of the crank. Since there is no internal oil pump, a full-length windage tray can be used to free up horsepower, and the oil pump can be easily adjusted outside of the engine. The oil is stored inside the oil pan like a wet-sump oiling system.
"A four-stage oiling system has three oil pump pickups in the oil pan itself. Each one of these pickups are plumbed to the three scavenge sections of the oil pump. In this type of oiling system, a full-length windage tray can be used inside of the oil pan, and the oil can be stored outside of the oil pan in a baffled dry sump tank. They're popular in racing classes that allow them; especially where low chassis height is important for good handling. Horsepower gain is maximized because there is virtually no oil in the pan and no internal pump, allowing the windage tray or screen to run the full length of the pan. Other advantages of a dry-sump system include a remotely mounted oil tank for increased capacity, the ability to easily add remote oil coolers, more consistent oil pressure, adjustable oil pressure, improved scavenging, and increased ring seal due to greater oil pan vacuum."
Thor Schroeder: "Oil longevity decreases exponentially as temperature increases, but oil doesn't flow freely when it's too cold. It's a balancing act, but there isn't an easy answer when it comes to the ideal temperature range oil should operate at. Optimal oil operating temperature can be different for different engines depending on engine tolerances and the type of oil used. Automakers often make engines run on the hot side for emissions at the expense of other factors. Hotter oil produces lower oil pressure and lower viscosity. Optimal oil operating temperature is also dependent upon water temperatures. At lower temperature levels, in the low 200-degree range, we have seen a 10-degree difference in oil temperature make 2 percent more horsepower on our dyno."
Mike Zeranski Jr.: "We recommend an oil operating temperature of at least 215 degrees, and build our oil cooler thermostats to operate above that temperature. By keeping the oil temperature above the boiling point of water condensation that may accumulate in the pan, it ensures that the water in the oil will evaporate out. Water significantly reduces oil life, and oil temps that are too cool will not allow the water to evaporate, especially if a motor is run for only short periods of time. Also, at this temperature the oil should achieve its intended viscosity and perform as designed, flowing and lubricating the engine most efficiently."
Thor Schroeder: "Some cars, particularly late-models, have problems with too much oil circulating back into the induction tract, which leads to detonation and compromises efficient combustion. From the factory, excess crankcase vapors and residual oil are vented back into the intake manifold. Moroso offers an air-oil separator that can be plumbed into the PCV system to capture this oil mist. This reduces the potential for detonation and the formation of deposits on the intake tract and valves. It has a billet aluminum body that complements any engine compartment and can be polished, chromed, or powdercoated for a custom look. It also features a bottom drain with an elbow that makes draining the collected oil a mess-free proposition. The kit includes a stainless steel mounting bracket, inlet and outlet fittings, and plenty of rubber hose for plumbing it up."
Pressure and Volume
Mike Zeranski Jr.: "An engine's oil pressure and the volume of oil being pumped by the engine are related, but having a high volume of flow does not necessarily mean high pressure, and high pressure does not necessarily mean there is high volume. Stock engines built with tight clearances can achieve adequate pressure with standard-volume pumps. As the engine clearances are loosened, it takes a greater amount of oil to fill and properly lubricate the clearances between engine components. In these situations, standard-volume pumps may not flow the necessary volume of oil to achieve the desired pressure and a higher-volume pump will be needed. Since the pressure achieved at any given volume of flow will be dictated by the design of the engine, we usually leave pump choices up to the engine builder. If the pump chosen has the volume to match the design and clearances of the engine, then pressure should take care of itself."
Bob Sanders: "It's best to have the least amount of wasted energy in your oiling system. So really the only difference between a big-volume pump and a small-volume pump is the rpm at which the regulator opens. Most engines flow between 9 to 14 gallons per minute, so if you compare our smaller 875 pump to our bigger 1100 pump, the 875 might take around 2,500 rpm at the crank to get up to full pressure whereas the 1100 would be there by 1,800. There are dozens of variables in all this, among them engine tolerances."
Bob Sanders: "Stock oil pumps are great for the range they normally run at since maximum engine rpm is usually low. Single-feed gerotor and spur-gear style pumps are inherently prone to cavitation for different reasons. The single-feed gerotor-style pumps have deficiencies on the suction chamber filling, while spur-gear pumps suffer from oil trapped behind their teeth. When this happens, oil can't escape fast enough to keep it from forcing bubbles back into a liquid state. We try to fill the suction side of our pumps as smoothly and slowly as possible, as this helps to minimize the formation of bubbles. Then we squeeze the oil using a slow sine wave pulse by incorporating a dual-feed gerotor. This slower pulse rate performs much better at high rpm.
"Billet housings can be carved out of many different materials. We use domestic-sourced aircraft grade 7055-T7. It has nearly 90,000 psi of tensile strength. We also hard anodize all our pumps in black to maximize heat transfer. Our machines can hold as close as 0.010-inch of tolerance. Titan professional pumps have axial needle bearings at both ends of the pump segment, and a needle bearing on the driver as well. We also use a premium quality seal on the main shaft. Professional pumps incorporate a discharge chamber for added protection.
"A great benefit of our pumps is that they're fully rebuildable. After disassembling them, we check the endplay and the bearing spacing. Next, we look at the relief circuit for wear and spring integrity. We always install new springs, then flow and pressure test all our pumps. The only time a pump is badly damaged is when hard steel parts, like the roller pins out of broken roller lifters, clog them up. Putting a magnet or two in the pan is an easy way to help save the pump."