Those of you who have been following along with our Tech Tuesday newsletters, we’ve covered what bore scoring is, how to identify if your Porsche engine has scored bores, and how to best try to prevent cylinder bore scoring in engines with Lokasil or Alusil blocks.

Unfortunately, many Boxster, Cayman, 911, Cayenne, Panamera, and Macan engines will still suffer cylinder bore scoring. The engines we most commonly see with bore scoring that are sent to us for repair include the 3.6 and 3.8 Porsche 911 996 and 997 engines as well as with the 3.4 engine used in Cayman S and late Boxster S models.

A diagnosis of scored bores doesn’t immediately mean your engine is dead. We see more and more engines being identified with bore scoring before symptoms have even manifested. This frequently happens when engines are bore scoped as part of the IMS pre-qualification procedure and through the use of used oil analysis to track iron, silicon, and aluminum wear levels in your Porsche’s engine oil.

We’ve seen many owners nurse an engine by switching to a thicker viscosity oil like Driven’s FR50 5w50 that also has increased moly levels allowing them to continue to drive their cars for months or even years until the symptoms become bad enough to require an engine rebuild or replacement. 

Although Porsche does offer engine shortblocks from the factory for Boxster, Cayman, and 911 models, these replacements do not address any of the inherent flaws associated with the factory Lokasil and Alusil cylinders and still require your shop to pull your existing cylinder heads, have them rebuilt, and then finish assembly of the engine to make it into a complete longblock. That said, for the same price, you can get additional value by rebuilding your existing engine rather than replacing it with another one from the factory. One such option is to use LN Engineering’s Nickies.

The first step would be to find a shop that is familiar with rebuilding the M96 or M97 engine unless you decide to tackle the rebuild yourself. A good resource would be one of the many IMS Solution Certified Installers, as all of them have completed hands on training with Jake Raby at The Knowledge Gruppe.

Alternatively, if you choose to rebuild the engine yourself, check out Rennvision’s Focus On: M9X Engine Assembly DVD series. This should be the first thing you purchase and watch before taking the next step. You might also want to check out their Porsche Torque Spec Book and M9X Engine Assembly Workbook as both enthusiasts and professionals alike will find these resource immensely valuable when it comes time to reassemble the engine.

Once you’ve chosen who is going to do the rebuild, the first step is to drop the engine and disassemble it. The engine block would then be shipped to us for our Nickies sleeving process. To make this easy, LN offers a pre-paid block shipping option where we ship you a custom box with molded inserts to ensure your case halves don’t get damaged in transit.

Where some other shops might offer slightly larger options using steel sleeves, our aluminum Nickies sleeves keep the engine running cooler and the NSC-plated bores, like those coated with Nikasil, reduce friction, all resulting in more horsepower through increased efficiency.

While the engine is apart, addressing the IMS issue is also a must. LN Engineering offers an intermediate shaft reconditioning service. This allows us to inspect the bearing housing bore for runout and also to pin the main drive sprocket, which can slip and cause a failure. We will also fit an IMS Retrofit or IMS Solution depending on what replacement ims bearing you want to go with.

During the reconditioning process, the block deck gets surface ground and depending on how much is required to straighten the case, custom MLS head gaskets in the correct thickness are provided.

For a street engine, we would also recommend a 160F low temperature thermostat to help keep the engine cool and ARP rod bolts to replace the weak factory rod bolts. This provides a solid and reliable foundation for a reliable engine for your Porsche Boxster, Cayman, or 911.

If you ever plan on autocrossing or tracking your Porsche, additional upgrades need to be made to address other weaknesses inherent to the M96/M97 engine. These upgrades include:

By replacing the above components during your engine rebuild, you are addressing the known issues associated with the Porsche M96 and M97 engine used in 1997-2008 Porsche Boxster, Cayman, and 911 models and will have a track ready engine that should give you years of reliable service with proper maintenance.

To simplify the reassembly process, LN Engineering offers engine rebuild kits for Porsche M96 and M97 engines including M96.01, M96.02, M96.04, M96.03, M96.05, M97.01, and M97.21 engine designations with everything we recommend replacing. We can also assist with cylinder head rebuilding and porting or anything else you might need when it comes to rebuilding your Porsche’s engine.

Outside of the products and services LN Engineering offers for rebuilding these Porsche engines, there are additional steps that should be taken such as having the crankshaft magnafluxed to check for cracks and having the journals polished. If your engine suffered a crankshaft failure as often happens if the engine fails on track, don’t bother trying to fix the crankshaft. It’s best to replace the crank with a known good one along with its matching crankshaft carrier. Be sure to check out our M96 engine warnings and precautions for more details.

If you have questions about rebuilding your Boxster, Cayman, or 911 M96, M7, or 9A1/MA1 engine, please do not hesitate to give us a call at 815-472-2939 or create a support ticket at https://support.LNEngineering.com – that’s what we’re here for. Same goes for those with Cayenne, Panamera, or Macan models that experience bore scoring as we have solutions to fix and prevent scored bores  for those Porsche models as well!