Porsche Plasma Bore Technology Explained: PTWA and RSW as the Evolution Beyond Nikasil

 

Porsche Plasma Bore Technology Explained: PTWA and RSW as the Evolution Beyond Nikasil

As Porsche engine design progressed into the modern era, one engineering challenge consistently shaped decision-making: long-term cylinder durability. Bore scoring in earlier water-cooled engines demonstrated that even advanced aluminum cylinder technologies have limits when subjected to modern emissions strategies, higher thermal loads, and increasingly tight tolerances. Porsche’s solution was not another variation of aluminum bore chemistry, but a shift to plasma-sprayed cylinder bore technology, now used in 718 and 991.2 and later Porsche sports car engines.

This technology is commonly referred to as PTWA (Plasma Transferred Wire Arc) or RSW (Rotating Single Wire). While the names differ, the underlying process and purpose are fundamentally the same. Both describe a plasma spray method in which a metal wire is energized into a plasma arc and deposited directly onto an aluminum cylinder bore to create a thin, iron-based wear surface. The differences between PTWA and RSW are largely matters of equipment configuration and nomenclature rather than function or outcome.

In practical terms, PTWA and RSW should be understood as variations of the same plasma bore coating technology, not competing or fundamentally different systems. The result in both cases is a dense, extremely wear-resistant cylinder surface that is mechanically bonded to the aluminum block and precision-finished for piston ring compatibility.

This represents a major departure from traditional cylinder designs such as Nikasil or Alusil. Those systems rely on aluminum alloy substrates to serve as both the structural cylinder and the wear surface. While effective under ideal conditions, aluminum-based bores are vulnerable to lubrication breakdown, thermal distortion, and piston instability. Once that balance is disturbed, the damage is progressive and irreversible.

Plasma-sprayed bores change that equation entirely. Instead of asking aluminum to perform a task it was never ideal for, the wear surface is engineered specifically for tribological stability. The sprayed coating resists scuffing, maintains oil film integrity, and tolerates tighter clearances without galling or smearing. This directly addresses the mechanisms that lead to bore scoring.

Another advantage of plasma bore coatings is thermal control. Aluminum expands significantly with temperature, which historically forced compromises in piston-to-wall clearance. Plasma coatings allow Porsche to manage expansion more predictably, stabilizing piston motion across cold starts, high load operation, and sustained heat. That stability is critical in modern direct-injected engines where localized temperature spikes are unavoidable.

Porsche’s adoption of plasma bore technology in the 718 Boxster and Cayman and the 991.2-generation 911 reflects a deliberate engineering pivot. Rather than continuing to refine aluminum bore chemistry, Porsche chose a surface technology already proven in high-performance and endurance applications. The move was not cosmetic or incremental—it was structural.

Importantly, this transition also marks a philosophical shift. Nikasil represented an earlier evolution in cylinder durability, replacing cast iron liners with a more advanced surface without the constraints of sleeving. Now that plating is considered a dirty operation and manufacturers are phasing this technologies out for environmental reasons, plasma bore coatings take the next step by eliminating the need for traditional liners altogether and separating cylinder wear from the aluminum block itself. In that sense, plasma spray technology can be viewed as a natural successor to Nikasil, designed for the demands of modern engines.

For Porsche owners and enthusiasts, understanding PTWA and RSW technology is essential to understanding where Porsche engine design is headed. The reduced incidence of bore scoring in these newer engines is not accidental. It is the result of rethinking the cylinder surface from first principles.

PTWA and RSW differ from APS coatings like SUMEbore or the thin-wall steel liners being used by VAG in some of the engines shared between platforms. Where PTWA and RSW make a plasma from a wire that is then applied to the cylinder bore, APS forms the plasma in a chamber before depositing it, starting from a powder instead of wire. What's in common is all of these plasma bore coatings don't require hazardous materials or special waste handling.

For those concerned that this technology is too new - rest assured, it's been around for decades, developed by Ford. Some of the earliest adopters of PTWA include Ford with its Coyote engine and even the Nissan GT-R.

As Porsche continues to refine and expand its use of plasma-sprayed bores, the message is clear. Cylinder surface engineering is no longer a compromise—it is the foundation of durability. And with plasma spray bore coatings, Porsche has embraced a solution that moves decisively beyond the limitations of traditional aluminum bore designs, proving there is life after Nikasil without fear of cylinder bore scoring.

Porsche M96 Rebuild: What It Really Means — and How to Do It Right

Porsche M96 Rebuild: What It Really Means — and How to Do It Right

The Porsche M96 engine, used in the 1997–2008 Boxster, Cayman, and 911 (996/early 997), has become one of the most discussed Porsche engines of the modern era. Searches for “Porsche M96 rebuild” often begin after an owner hears about bore scoring, IMS bearing failures, or oil consumption concerns.

But not all engine rebuilds are the same — and understanding the difference between a basic repair and a properly engineered solution for a Porsche M96 rebuild is critical for long-term ownership.

This article explains what an M96 rebuild actually involves, when it makes sense, and how LN Engineering and Flat 6 Innovations approach these engines differently than typical rebuild shops.

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What Is a Porsche M96 Rebuild?

At its simplest, an M96 rebuild refers to disassembling the engine, replacing worn or damaged components, and reassembling it to operating condition. In practice, the scope varies widely.

Some rebuilds focus on:

• Replacing failed bearings or damaged pistons

• Refreshing rings, bearings, and gaskets

• Returning the engine to factory specifications

Others go much further, addressing known design compromises in the original engine to improve durability, stability, and service life beyond what Porsche originally delivered.

Understanding which path is appropriate depends on the engine’s condition, intended use, and ownership goals.

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Common Porsche M96 Engine Issues (Briefly Explained)

The M96 engine and it's twin, the M97 engine, has several well-documented concerns:

• Cylinder bore scoring due to open-deck block design and localized thermal distortion

• Intermediate shaft (IMS) bearing failures in certain model years

While these issues are widely discussed online, not every engine experiences them, and not every engine is a good candidate for rebuilding once damage occurs.

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When an M96 Rebuild Makes Sense — and When It Doesn’t

One of the most important distinctions made by experienced Porsche engine specialists is this:

Not every M96 engine should be rebuilt.

Severe overheating, extensive bore damage, crankcase distortion, or oil starvation events can leave a block beyond economical or reliable repair. Rebuilding such an engine may restore function temporarily but increases long-term risk.

This is why LN Engineering and Flat 6 Innovations emphasize:

• Thorough inspection before approving a rebuild

• Clear limits on what is considered rebuildable

• Honest guidance when replacement or re-engineering is the better option

This approach filters out high-risk builds and protects owners from investing heavily in engines that cannot deliver long-term reliability. What this boils down to is that in some cases you are better off starting from another core engine.

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Rebuild vs. Engine Program: A Critical Difference

Many shops “rebuild” engines. And saying it's rebuilt is far too kind in some cases - some just throw things together and hope for the best. Far fewer develop engine programs. 

Even fewer train other professionals on how to rebuild Porsche M96 engines and have published DVDs and books on the topic.

A traditional rebuild replaces failed components.
An engine program addresses the root causes of failure.

LN Engineering’s work on the M96 platform over more than two decades has focused on understanding why these engines fail and developing solutions that improve the underlying architecture — not just the symptoms. And it didn't stop there - we've developed fixes for dozens of known issues and upgrades to bring out the full potential of any Porsche M96 rebuild.

This distinction matters for owners planning to keep their cars long-term.

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How LN Engineering Approaches the Porsche M96

LN Engineering’s role in the M96 ecosystem centers on engineering solutions and critical components, including:

• Advanced cylinder technologies designed to stabilize the block

• Precision machining processes for improved bore geometry

• Proven upgrades to address known failure points

• Parts and systems designed for compatibility with real-world use

LN Engineering does not position every M96 engine as a rebuild candidate. Instead, engines are evaluated based on condition, intended use, and whether corrective engineering will meaningfully improve longevity.

Likewise, Flat 6 Innovations knows it can't rebuild every Porsche engine itself. That's why Flat 6 Innovations has a network of certified installers who have also been trained on how to rebuild the M96 engine. This gives owners more choices backed by LN Engineering and Flat 6 Innovations. 

Owners looking to learn more about available components and upgrades can explore LN Engineering’s M96 engine parts and upgrade offerings, which reflect decades of applied research and testing.

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Flat 6 Innovations: Purpose-Built M96 Engine Programs

Flat 6 Innovations (FSI) represents the next step beyond a conventional Porsche M96 rebuild.

FSI engine programs are:

• Built in limited numbers

• Assembled deliberately, not on production timelines

• Designed around stability, thermal control, and longevity

• Matched to owner goals rather than minimum cost

Many Flat 6 Innovations engines are commissioned before failure, by owners who want to eliminate known M96 compromises and enjoy their cars with confidence for years to come.

This is a fundamentally different mindset from reactive, failure-driven rebuilds — and one reason FSI engines command higher investment while delivering greater long-term value.

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Choosing the Right Path for Your Porsche M96

For owners researching a Porsche M96 rebuild, the most important first step is not pricing — it’s evaluation.

Key questions to consider:

• Is the engine structurally sound enough to justify rebuilding?

• Are the underlying causes of failure being addressed, or only the symptoms?

• Does the builder define clear limits and standards for what they will accept?

• Is the solution aligned with short-term resale or long-term ownership?

Extreme warranty claims, one-size-fits-all solutions, or rebuilds offered without meaningful inspection and clearly defined outcomes should be approached cautiously. High-performance engines are mechanical systems with known wear mechanisms, especially under track or high-load use.

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Final Thoughts on Porsche M96 Rebuilds

A Porsche M96 rebuild can mean very different things depending on who performs the work and why. For some owners, a basic refresh may be appropriate. For others, especially those planning long-term ownership, addressing the M96 engine’s known design compromises through engineered solutions offers a far better outcome.

LN Engineering and Flat 6 Innovations approach the M96 platform with a focus on standards, transparency, and long-term reliability, not speed or volume. That philosophy naturally results in fewer builds — but better engines.

For owners seeking clarity rather than urgency, understanding these differences is the key to making the right decision.

Porsche 996 Engine Rebuild: A Smarter Investment Than a Used Engine

A Porsche 996 engine rebuild is often approached with hesitation due to cost, leading many owners to consider used engines as a shortcut. In reality, used engines frequently introduce more risk and expense over time, especially given the prevalence of bore scoring and other age-related failures.

While many shops claim expertise with M96 engines, only a small number have decades of direct experience rebuilding, upgrading, and engineering solutions for their known weaknesses. LN Engineering and Flat 6 Innovations have been involved in developing many of the industry’s corrective upgrades, while also training professionals and enthusiasts through The Knowledge Gruppe.

Used engines, even those with bore scope inspections or limited warranties, still require significant investment. Labor, fluids, seals, and wear items are not covered, and most installs require immediate updates such as a new water pump, air-oil separator, and often an IMS solution. If that engine later fails, those costs are unrecoverable.

A comprehensive rebuild addresses the root causes rather than deferring them. While a fully upgraded rebuild can reach $30,000–$40,000, it often represents better long-term value than replacing the car or installing an unknown engine.

LN Engineering supports multiple rebuild paths, including complete rebuild kits, engines from trusted partners like Flat 6 Innovations and RND Engines, Certified Installer networks, and DIY education through M96/M97 engine assembly courses and DVDs from The Knowledge Gruppe.

In the long run, a properly rebuilt 996 engine is not just a repair—it is a reset.

Porsche Pistons: Matching Components for Long-Term Engine Health

Selecting Porsche pistons involves far more than choosing a reputable brand or the correct bore size. Modern Porsche engines are highly sensitive to how pistons and cylinders interact, and mismatched components can lead to excessive noise, oil consumption, poor ring seal, and premature wear. Mahle is in a key position as an OEM supplier to Porsche, on the leading edge of development and manufacturing, with 3d printed pistons being their latest development when it comes to Porsche pistons.

Built on Mahle's legacy and trusted name, LN Engineering offers exclusive piston and cylinder systems using Mahle Motorsports pistons, engineered specifically to work with LN Engineering Nickies® cylinders. This pairing is designed as a complete system, accounting for thermal expansion rates, bore stability, and surface finish. The result is improved durability, tighter operating clearances, and superior heat transfer under demanding conditions.

For builders who prefer a factory-style appearance or wish to retain OEM architecture, LN Engineering also supplies Mahle Motorsports piston and cylinder kits using cast aluminum Nikasil-plated cylinders. These assemblies maintain the original visual and structural characteristics while benefiting from Mahle’s motorsports-level piston design and manufacturing precision.

The critical takeaway is that piston selection should never be isolated from cylinder choice. Different cylinder materials behave very differently under load and temperature, and pistons must be designed accordingly. LN Engineering’s matched solutions remove that guesswork by ensuring compatibility from the start.

Porsche IMS Bearing: Why It’s Still a Critical Ownership Issue

The Porsche IMS bearing is one of the most important topics for owners and buyers of water-cooled Porsche models from the late 1990s through the late 2000s. While the issue has been discussed for years, it continues to catch new owners off guard—often because they believe the problem is either rare, already solved, or no longer relevant.

The IMS bearing supports the intermediate shaft that drives the engine’s cam timing. When this bearing fails, the result is frequently catastrophic engine damage. Porsche revised the bearing design multiple times, but none of the factory versions eliminated the underlying risk. As these cars age, the likelihood of failure increases due to time, mileage, and lubricant degradation.

A major source of confusion is the continued use of failure rate statistics from the Eisen class action lawsuit. Those figures were based on data collected many years ago, when the vehicle population was significantly younger. Today’s cars are operating well beyond their original design lifespan, making those numbers increasingly irrelevant.

Another misunderstanding is the belief that an upgraded IMS bearing is permanent. Many replacement bearings still require scheduled replacement. Only pressure-fed plain bearing conversions eliminate the service interval entirely.

For buyers and owners alike, the most important factor is documentation. Knowing whether the IMS bearing has been addressed, how it was addressed, and whether it requires future service is essential to protecting the engine and the investment.

Porsche M96/M97 Camshaft Deviations: What They Are, Why They Happen, and How to Fix Them

Porsche Camshaft deviation is the measured difference (in degrees) between each bank’s camshaft position and the crankshaft’s position. The ECU calculates this using the crankshaft position sensor and the camshaft position sensors. Excessive deviation points to wear, setup errors, or control issues in the timing system.

Engines Covered

This guide focuses on Porsche M9x engines with intermediate shafts (1997–2008): the early 5-chain design and the later 3-chain design. It does not cover the MA1/9A1 engines (2009+), which use different hardware and rules.

Baseline Numbers

• Factory allowance: about ±6° of camshaft deviation.
• Practical target: keep it within about ±4° hot at idle.
• When to measure: engine fully warm, A/C off, stable idle.

5-Chain vs 3-Chain — Why It Matters

The early 5-chain engines (to MY2001 996 and through MY2002 Boxster) carry more parts: extra simplex chains between intake and exhaust cams and additional wear pads and adjuster hardware. More parts means more potential wear points and, typically, higher deviation risk. The later 3-chain engines (2002+ 911, 2003+ Boxster/Cayman) simplify the system and commonly show fewer wear-related deviation causes.

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Common Causes on 3-Chain Engines

1. Vane-cell cam phaser (intake) issues. Contamination, varnish, or internal wear can drive deviations. Shorten oil service intervals and recheck; many borderline numbers improve after fresh oil and a few hundred miles. If not, the adjuster may be failing.
2. Retaining bolt slippage (early 2002 996). An intake phaser retaining bolt that didn’t achieve proper yield/torque can let the phaser move under load, building in a false deviation. Replace the bolt and retime.
3. Master chain stretch or quality problems. Premature stretch or link failure has been seen on some early 3-chain engines (notably early 2002 996). Stretch increases deviation and sheds magnetic debris; check the sump, filter, and magnetic drain plug. Long drain intervals and lots of carbon (soot) in the oil will cause the timing chains to stretch.

Note: IMS bearing condition is seldom a primary driver of measurable deviation on a 3-chain unless the bearing is catastrophically failing (in which case the engine usually isn’t running).

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Common Causes on 5-Chain Engines

1. Simplex chain wear pads (bank-to-bank cam links). The small guides on the “4th & 5th” chains wear, generating brown plastic debris and large negative deviations. This is the #1 issue on 5-chain engines.
2. Hydraulic cam adjuster unit or solenoid failure. When these fail, deviations can jump to the 20–25° range. Verify electrical vs hydraulic cause before replacing the unit; the solenoid can also be at fault.
3. Intermediate-shaft drive chain and main rails. Wear or stretch adds equal deviation to both banks. Check chain deflection and rail condition.
4. Crankshaft position sensor aging. A marginal CKP sensor can cause hot-start stalls, tach jumps, and reliability issues; it’s inexpensive and worth replacing on age alone.
5. Stacked tolerances + oil/service history. Old oil, long intervals, and low average road speed (city use) accelerate wear of early guide materials.

“Sensor Out of Range” Doesn’t Always Mean a Bad Sensor

A diagnostic code for a camshaft sensor “out of range” usually means the measured position is outside allowable limits, not that the sensor has failed. Before parts swapping, pull live data with a proper tool and evaluate actual deviations.

How to Check Properly

• Use a Porsche-capable scan tool (Durametric, PIWIS, Autologic, etc.).
• Warm the engine fully, turn A/C off, observe Bank 1 and Bank 2 deviations at idle.
• Log data during gentle load and rpm changes; on 3-chain engines, intake phasing varies continuously with load, temperature, and oil pressure.
• If deviations exceed practical limits, investigate before further driving.

Early Warning Clues

• Oil/filter autopsy: brown plastic (worn 5-chain pads), black ferromagnetic fines (chain wear), mint-green fragments (certain adjuster internals).
• Magnetic drain plug: helps capture steel debris; check at each service.
• DTCs: cam correlation or out-of-range codes, especially with repeat occurrences.

Repair Overview (5-Chain Wear Pad Job)

This is a summary, not a step-by-step. Follow a workshop manual or a dedicated training resource for procedures and torque specs.

1. Engine access: Removing the engine is strongly recommended (especially on 911). Boxster/Cayman can be done in-car but access is limited.
2. Lock at TDC: Pin the crank at TDC before disassembly; keep it locked until timing is reset.
3. Tooling: Use correct holding fixtures and bridges (e.g., Baum Tools kit) to support cams with the cam cover off; use the proper compressor tool for the hydraulic chain adjuster (RH or LH thread as fitted).
4. Mark timing: Note factory chain mark locations (discolored links and cam dots). If replacement chains lack marks, transfer them before assembly.
5. Replace parts: new simplex chains, new wear pads (pairs per bank), inspect/replace adjuster unit and solenoid as indicated.
6. Retiming: Set mechanical timing with fixtures, release adjuster preload correctly, and verify deviations hot at idle.

Prevention and Service Strategy

• Oil matters: Shorter service intervals and quality oil reduce varnish and phaser issues. Old, fuel-diluted, or moisture-laden oil accelerates wear.
• Drive pattern: Cars with very low average speed and long idle time often fare worse than those with regular highway use.
• Monitor regularly: Periodic deviation checks and oil/filter inspections catch problems early.

Bottom Line

Camshaft deviation is a powerful health indicator on M96/M97 engines. On 3-chain cars, look first at the intake phaser, its hardware, and chain condition. On 5-chain cars, worn simplex-chain guides are the usual suspect, with adjuster failures producing the largest numbers. Diagnose with the right tool, confirm mechanically, and address issues before debris and correlation faults snowball into major engine damage.

Porsche “Vehicle Handover” vs. Manual ECU Hard Reset: What to Know

Just rebuilt your Porsche engine or replaced fuel, ignition, or sensor components? You may have heard you need to perform a vehicle handover. That’s correct—but there’s a difference between a full factory handover and a basic hard reset.

What a Vehicle Handover Actually Does

A true vehicle handover resets adaptations and calibrations across relevant control modules. It is performed with the Porsche factory PIWIS diagnostic tool and walks each module through the proper reset procedures. If you have access to PIWIS (or an authorized shop), this is the preferred method after major work. Unfortunately, a Durametric or most other non-Porsche diagnostic tools will not allow you to perform a vehicle handover or system adaptation. 

No PIWIS? Do a Manual ECU Hard Reset

If a factory handover isn’t available, you can still clear fuel trims and learned behavior with a safe, manual hard reset, referred to by Tony Callas of Callas Rennsport as a "Mini Vehicle Handover". This won’t replace a full handover, but it gives the ECU a clean slate so it can relearn.

Step-by-Step Hard Reset

1. Turn the ignition off and remove the key. Wait at least 60 seconds for modules to sleep.
2. Disconnect both the negative and positive battery cables from the battery.
3. Using a 12V incandescent test light (do not use LED or fluorescent), connect the test light between the two cables (clamp to clamp), not to the battery posts.
4. Leave the test light connected for about 10 minutes to safely discharge residual voltage in the system. The bulb may not glow—this is normal.
5. Remove the test light. Reconnect the battery cables (positive first, then negative) and ensure tight, clean connections.
6. Turn the ignition to ON (do not start) and let modules fully initialize for 30–60 seconds.
7. Start the engine and allow it to idle. Then drive normally so the ECU can relearn fuel trims and idle control.

Important Notes

• This procedure will clear DTCs (check-engine lights) and reset OBD-II readiness monitors. You’ll need to complete the appropriate drive cycles before emissions testing.
• Expect to re-configure user settings: clock, radio presets, one-touch window pinch protection, seat memory, etc.
• If the battery has been weak, consider testing or replacing it; unstable voltage can corrupt learned values and trigger false faults.
• After major engine work, including engine rebuild or engine replacement, monitor fuel trims, idle quality, and cold-start behavior over several drive cycles. Address vacuum leaks, injector issues, or MAF problems promptly.

Bottom Line

A factory PIWIS vehicle handover is the gold standard after significant repairs, as it resets and calibrates multiple modules correctly. When PIWIS access isn’t available, a manual ECU hard reset is a safe way to clear old adaptive data so the engine management can relearn. Just remember: you must drive and confirm OBD2 readiness flags before any inspection can be carried out.

Piston Skirt Coatings for Alusil and Lokasil Engines: What Matters and Why

Modern aluminum engine blocks such as Alusil and Lokasil rely on exposed silicon crystals within the cylinder wall for wear resistance. Because these bores do not use iron liners, pistons require a ferrous skirt coating to prevent aluminum-on-aluminum contact and galling. Overlooking this detail can turn a healthy engine into a bore-scored core in a hurry, especially without proper maintenance.

Why Ferrous Coatings Are Essential

Without a ferrous barrier on the piston skirt, the aluminum piston can contact the silicon-rich aluminum bore surface. Once that happens, the result is rapid galling and, soon after, bore scoring. Either outcome can force an expensive repair—boring and sleeving the block or replacing it entirely.

Two Proven Approaches: Ferrostan and Ferroprint

Mahle developed two widely used skirt coatings for Alusil/Lokasil applications—both seen in high-performance engines from Porsche, BMW, and Mercedes-Benz. They differ in construction, application method, and long-term durability.

Ferrostan (Electroplated Iron/Tin)

• What it is: A dual-layer electroplated coating—an iron layer for wear resistance topped with a thin tin layer to aid break-in.
• How it’s applied: Electroplating bonds the iron layer metallurgically to the piston skirt.
• Why it matters: The bonded iron layer is extremely hard and durable, offering excellent long-term protection under high load and temperature.
• Trade-offs: Electroplating involves chemicals and processes with environmental considerations; many manufacturers reduced or phased out this method in favor of alternatives.

Ferroprint (Resin with Stainless Particles)

• What it is: A polymer-resin coating infused with stainless steel particles.
• How it’s applied: Typically screen-printed or sprayed onto the skirt, then cured.
• Why it matters: Easier to apply and generally more environmentally friendly from a manufacturing standpoint.
• Trade-offs: While effective within its limits, it does not typically match Ferrostan’s long-term durability in severe service.

Durability and Failure Modes

Historical field experience shows Ferrostan holds up exceptionally well in demanding conditions, with very low incidence of bore scoring when used correctly. Ferroprint offers a cleaner production process and solid performance for many applications, but it is generally considered less durable over extended high-load, high-heat use.

If either coating is damaged during assembly—or simply worn through in service—the aluminum piston skirt can contact the Alusil/Lokasil bore. That metal-to-metal contact accelerates wear, leading first to scuffing and galling, then to visible scoring that compromises sealing and oil control.

Best Practices for Builders and Owners

• Specify the right pistons: Use pistons specifically engineered for Alusil/Lokasil with an appropriate ferrous skirt coating. As of writing this, Mahle Motorsport is the only aftermarket piston manufacturer that offers the required coatings.
• Match use to coating: Ferroprint is not compatible with other cylinder bore technologies, like Nikasil or even cast iron cylinder bores.
• Inspect before assembly: Verify continuous, intact skirt coverage; avoid nicks or handling damage that could become failure initiation sites.
• Use correct clearances: Follow the piston manufacturer’s clearance and finish requirements for Alusil/Lokasil bores.
• Control lubrication and break-in: Proper assembly lube, first-start procedure, and early oil changes reduce risk during the most vulnerable hours of operation.

Bottom Line

In Alusil and Lokasil engines, skirt coating choice is not cosmetic—it is fundamental to reliability. Ferrostan provides the most robust long-term protection, but it's not used anymore; Ferroprint is a viable, cleaner-production alternative when used within its operating limits, requiring the correct bore prep, clearances, and engine oils. Choose wisely, assemble carefully, and you greatly reduce the risk of bore scoring.

Ethanol-Blended Gas and Older Cars: What You Need to Know

If you drive an older car—especially one with a carburetor or early fuel injection—ethanol-blended gasoline can cause problems that regular maintenance won’t catch. Modern pump fuel typically contains 10% ethanol (E10), and some blends reach 15% (E15). Understanding how ethanol behaves will help you avoid corrosion, drivability issues, and expensive repairs.

Why Ethanol Is Different

Hygroscopic behavior. Ethanol is hygroscopic, meaning it absorbs moisture from the air. In vented classic-car fuel systems, that moisture can accumulate and promote corrosion in fuel tanks, lines, carburetors, and steel hard lines.

Phase separation. When enough water is absorbed, the water/ethanol mix separates from the gasoline and sinks to the bottom of the tank. Engines may then ingest a water-rich layer, causing hard starts, misfires, rust, and potential damage.

Lower energy content. Ethanol has less energy per gallon than gasoline. Older engines may run leaner on the same jetting or fueling strategy, leading to hesitation, higher temps, or detonation risk if not corrected.

Common Symptoms on Classics

• Hard starting after sitting a few days or weeks
• Rough idle, hesitation, or stumble on tip-in
• Corroded tanks, senders, and carburetor internals
• Swollen, softened, or cracked rubber hoses and seals
• Clogged filters from loosened varnish and debris

Materials and Components at Risk

Older rubber compounds (nitrile, neoprene) and certain plastics weren’t designed for alcohol exposure. Over time, they can swell, soften, or crack. Brass, zinc, and pot-metal carb parts may corrode more quickly in the presence of water-laden ethanol fuel. That's one reason why using a fuel additive containing PEA, like Driven Injector Defender or Driven Carb Defender at every fill up on cars made before 2000 is a must, especially carbureted models.

Prevention and Best Practices

• Use ethanol-free fuel where available, especially for seasonal or infrequently driven vehicles.
• Upgrade fuel hoses and seals to modern ethanol-resistant materials (e.g., SAE J30R9/J30R14-rated hose). Replace accelerator pump diaphragms, needle/seat assemblies, and o-rings with ethanol-compatible versions.
• Re-jet or retune carburetors if needed to correct lean operation caused by ethanol’s lower energy content.
• Add a quality stabilizer like Driven Storage Defender before storage and run the engine long enough to pull treated fuel through the system, if the fuel won't be used within 30 days. For longer storage, drain carb bowls or run the engine dry.
• Keep the tank full to reduce humid air space and slow moisture uptake; use a tight-fitting fuel cap.
• Service on schedule: replace filters more often during the first months after switching fuels; inspect tanks and senders for rust.
• Mind the label: E15 is not approved for most pre-2001 vehicles and many small engines; avoid misfueling.

Storage Tips

For vehicles that sit, combine several strategies: ethanol-free fuel if possible, stabilizer, full tank, drained carb bowls, and periodic start-ups with a gentle drive to operating temperature. This reduces phase separation, varnish formation, and corrosion.

If the fuel is older than 3-4 months and a stabilizer was not used, unfortunately you'll want to pump that fuel out and put fresh fuel in. 

Quick Checklist

• Confirm local fuel blend (E0/E10/E15)
• Inspect and replace aged rubber hoses with ethanol-rated lines
• Refresh carb soft parts (seals, diaphragm, needle/seat)
• Consider minor re-jetting or tuning adjustments
• Use stabilizer for any storage beyond a few weeks
• Replace the fuel filter after the first few tanks and then annually
• Check tank, sender, and lines for corrosion at service intervals

Bottom Line

Ethanol blends aren’t an automatic deal-breaker, but older fuel systems need the right materials, maintenance, and storage practices to stay reliable. Address hoses, seals, and tuning proactively and you’ll avoid most ethanol-related headaches.

Pre-Purchase Inspections for Porsche Boxster, Cayman, and 911: What Most Shops Miss

Shopping for a used Porsche Boxster, Cayman, or 911? A Porsche pre-purchase inspection (PPI) is essential. But even careful inspections can miss the issues that matter most—especially on M96 and M97 engines. Here’s a practical guide to what a thorough Porsche PPI should include, and why the usual “once-over” isn’t enough.

Bore Scoring: The Big One

Scoping through the spark plug hole isn’t sufficient. A proper inspection must include a borescope from the sump, with special attention to cylinders 4–6 on M96 and M97 engines. That’s where scoring commonly begins, and it can be completely hidden from the top.

Don’t assume the later 9A1/MA1 engines are immune. They can suffer cylinder bore scoring too and should be scoped.

Fuel Trim Values Tell the Truth

Ask for fuel trim data—both short- and long-term—along with FRA and RCAT values. These metrics reveal how the engine is actually running and can uncover vacuum leaks, injector imbalance, and MAF sensor issues that a quick test drive won’t show.

Over-Rev Report (Ranges)

Generic scan tools can’t read Porsche over-rev data. Use a proper diagnostic tool (e.g., Durametric or PIWIS) to pull the over-rev report. It shows whether the engine has been money-shifted or abused; the data is stored permanently in the ECU.

Crankcase Vacuum and the AOS

Measure crankcase vacuum with a manometer. Low or excessive vacuum, whistle noises, or smoke at startup often point to a failing air-oil separator (AOS). It’s a simple test that can save a lot of guesswork.

Cooling System Reality Check

If the water pump is more than 4–6 years old, plan to replace it. The same goes for an original expansion tank—age alone is a risk. Poor bleeding practices can trap air pockets that create hot spots and crack heads. Confirm service history or budget for preventative maintenance.

Old Fuel and Dirty Injectors

Stale fuel and marginal injectors cause rich cold starts that wash the cylinders and undermine ring seal. Review fuel trim logs and observe a true cold start. If the car sat for long periods, expect to address the injectors and fuel system.

Vacuum Leaks (Smoke-Test It)

Plastic lines get brittle and crack with age. The only reliable way to find small leaks is with a smoke test. Minor leaks can wreak havoc on drivability, fuel economy, and trim values.

Oil Level Matters

Overfilling these engines can hurt ring seal and overload the AOS. Verify the oil level on a level surface after the car has sat at least eight hours. If the seller can’t demonstrate proper procedure, double-check it yourself.

IMS Bearing: Upgrade ≠ Forever

Unless it’s the oil-fed plain bearing solution (e.g., IMS Solution), ball or roller IMS bearings have service intervals based on time and/or mileage. “Upgraded” does not mean “permanent.” Confirm the install date and mileage, and plan accordingly.

Drop the Sump and Cut the Filter

As Jake Raby says, dropping the sump is like “looking through a window into the engine’s soul.” Inspect for metal or debris. Always cut the filter open and consider sending an oil sample to a lab for analysis. It’s inexpensive insurance.

Carfax and Autocheck: Useful, Not Definitive

These reports can help with history, but many shops never submit data—especially for body repairs or engine work. Don’t rely on them alone; they can create a false sense of security.

Ownership Patterns That Raise Flags

• Multiple owners in a short period of time.
• Long stretches of storage with very little mileage.
• Spotty service records or missing documentation for major maintenance.

The Bottom Line

A real Porsche PPI goes beyond cosmetics and a short test drive. If the inspection doesn’t include a sump-side borescope, a smoke test, fuel trim logs, an over-rev report, and used-oil analysis, you’re not getting the full story. The cheapest Porsche you find can become the most expensive to own if these steps are skipped.

Quick PPI Checklist

• Borescope from sump; focus on cylinders 4–6 (M96/M97) and verify 9A1/MA1 as needed.
• Fuel trims (including FRA/RCAT) and cold-start behavior.
• Over-rev ranges pulled with Durametric/PIWIS.
• Crankcase vacuum measurement (manometer) to assess AOS health.
• Cooling system: water pump age, expansion tank condition, proper bleeding.
• Smoke test for vacuum leaks.
• Correct oil level procedure verified.
• Sump inspection, filter autopsy, and used-oil analysis.
• Service history vetted; ownership pattern reviewed.

Next Steps

Use due diligence and choose a reputable Porsche specialist who understands your specific model and engine generation.