Things every Boxster, Cayman, and 911 owner should know before tracking their Porsche

Even though the M96 and M97 engine is advertised as having an "integrated dry-sump", in essence it is a wet sump engine. Unlike prior generations of aircooled Porsche 911 models that featured true dry sump oiling, M96 and M97 engines can suffer from Porsche oil starvation related failures when tracked or raced. If you choose to track your Porsche Boxster, Cayman, or 911 996 or 997, there are extra steps that need to taken to prevent costly engine damage.

However, you do not need to be overly worried about damaging your engine while driving your Porsche spiritedly on the street. M96 and M97 oil starvation related engine failures typically occur on Boxster, Cayman, and 911 996 and 997 models when running tires with treadwear ratings of 200 or less, like what is found with ultra-high performance summer tires, R-compound, or racing tires. Sticky tires allow drivers to go faster and as a result, pull higher G-forces than you could otherwise on street tires. Further vehicle modifications to the suspension and brakes can further exacerbate these issues. This results in situations where oil is pulled away from the oil pickup, causing oil aeration or full blown oil starvation. This can lead to spun rod bearings as well as damage to main bearings or any components that rely on pressurized engine oil for proper lubrication. 

There are several things that can be done to the M96 and M97 engine to mitigate the problem of oil starvation.

The first thing to do is use a race oil when tracking your Porsche. True race oils, like those offered by Driven Racing Oils, are formulated with added anti-wear and anti-friction additives. They also have lower levels of detergents and dispersants, which allows the oil to work better to protect your engine, since engine cleanliness isn’t a priority here. Another big difference is that race oils tend to have higher levels of anti-foaming agents and are formulated with better base oils for improved viscosity retention. 

The simplest thing you can do to minimize the chances of suffering an oil starvation related failure is to install a deep sump on your Porsche engine. The oil volume helps reduce peak oil temperatures and increases total oil system volume. The most common upgrade to improve oil pressure on track for Boxster, Cayman, and 911 996 and 997 models with the M96 or M97 engine is to install the LN Engineering 2 quart Porsche deep sump. This deep sump also features additional baffling to aid in controlling oil sloshing that can occur under high G-forces and includes 997 oil return tubes that are designed to help return the oil from the heads to the sump faster.

Another option is to install an Accsump oil accumulator. During high-speed maneuvers such as cornering, braking, or acceleration, the oil inside the engine can shift away from the pickup tube of the oil pump, momentarily starving the pump and causing a drop in oil pressure. An accumulator is charged with pressurized air on one side and oil on the other. When oil pressure drops below a certain threshold, the accumulator releases oil into the engine, maintaining continuous oil pressure until the normal oil flow resumes.

There are two additional problems that lead to oiling related failures on the M96 and M97 engine. 

The first problem is that the oil tends to be centrifuged out to the heads under sustained G-forces, where it can't be returned fast enough to the sump by the scavenge pumps that are located in the cylinder heads. As part of the X51 package, Porsche offered a tandem scavenge pump with a second suction stage, allowing the oil to be scavenged from both ends of the cylinder head. Oil that otherwise would be trapped in the cylinder heads, even under sustained high G-forces, can be returned to the sump. This solution, in combination with an LN Engineering 2 quart deep sump or a Porsche Accusump, provides the best protection against oil starvation. 

The second issue leading to oil starvation is high oil temperatures. This leads to viscosity loss and makes the oil aeration problem that much worse. For most Porsche models, Driven XP9 racing oil is the best choice when tracking a Porsche with the M96 or M97 engine. However in warmer climates or with modified engines, it is common to use a higher viscosity oil such as Driven XP6, especially if the oil will see temperatures approaching 240F or higher. Just remember that race oils are not intended for extended use – they are typically good for about 500 miles, or one track weekend.

Although seemingly linked to oil starvation issues, rod bolt failures are also common in Boxster, Cayman, and 911 996 and 997 models, even those that have not experienced over-revs, which are most commonly caused by a mis-shift. For example, bouncing the engine off the rev limiter repeated puts stresses on the weak factory rod bolts. This also means that you shouldn’t install an ECU tune that raises your rev limiter either, as that is just inviting disaster. Remember, these stresses are cumulative, and eventually you’ll spin a rod bearing, the rod bolts will stretch, or the rod bolts will break.

Although a very popular upgrade on air-cooled Porsche engines, the use of a lightweight flywheel as a performance bolt-on is not recommended for M96 or M97 engines. Although many have found ways to make them work by properly balancing entire rotating assemblies to reduce vibration, using sprung clutches, and adding harmonic dampening crank pulleys, retaining the factory dual mass flywheel (DMF) is still recommended. The dual mass flywheel serves to dampen harmonics within the engine, and without this dampening, the crankshaft can break, especially when subjected to track use. 

Another common cause of engine failure or damage on track in Boxster, Cayman, and 911 996 and 997 models is caused by a failing or faulty air oil separator. If the Porsche AOS fails, oil can enter the intake system. Best case scenario, it will cause your engine to smoke excessively. In extreme cases, if enough oil enters the combustion chamber, it can lead to hydrolock, which occurs when a liquid substance prevents the pistons from moving. Since liquids are incompressible, this can cause severe engine damage, including bent or broken rods, damaged crankshafts, and more. The best way to prevent engine damage on track is to replace the factory air oil separator on an M96 or M97 engine with an upgraded Porsche Motorsport AOS or a UAOS.

The steps we have outlined in this article are above and beyond typical preparation one would expect to have to do before tracking their Porsche such as checking or servicing your tires, brakes, suspension. Before taking your Porsche to the track, it is important to have your car thoroughly inspected by a professional that is an expert on Boxster, Cayman, and 911 996 and 997 models who is thoroughly versed in the intricacies of what it takes to make an M96 or M97 engine survive on track.