1999 Porsche Boxster 2.5L M96.20 Engine
2.5L • M96.20 • Flat-6 • DOHC • 24-Valve • Gasoline
The 1999 Porsche Boxster uses the M96.20 2.5L horizontally opposed six-cylinder engine, part of the first-generation 986 Boxster powertrain family.
If you're looking for a replacement engine, matching the engine type, model year and complete vehicle identification information is important before purchasing.
1999 Porsche Boxster Engine Overview
The 1999 Porsche Boxster engine is a 2.5-liter water-cooled flat-six designated M96.20. Unlike a conventional V6, the cylinders are arranged horizontally opposite each other, giving the engine its characteristic boxer layout.
The M96.20 uses six cylinders, four overhead camshafts and four valves per cylinder, for a total of 24 valves. Porsche's technical documentation also describes an integrated dry-sump lubrication system, hydraulic valve-clearance compensation and VarioCam camshaft adjustment.
The engine has a displacement of 2,480 cc, with an 85.5 mm bore and 72 mm stroke. Factory technical data lists 150 kW / 201 SAE horsepower at 6,000 rpm and 245 Nm / 181 lb-ft at 4,500 rpm.
For anyone shopping for a replacement, the important thing is not simply finding a 2.5L Porsche engine. The correct engine family, year, transmission configuration and vehicle identification should be verified.
1999 Porsche Boxster 2.5L Engine Specifications
Key specifications for the 1999 Porsche Boxster M96.20 2.5L flat-six engine, including engine identification, displacement and performance.
Need a Used Porsche Boxster Engine?
Replacing an engine in a Porsche is different from replacing a typical mass-market engine.
The Porsche Boxster uses a mid-engine layout, and the engine assembly contains several application-specific components that should be matched correctly.
A used Porsche engine can be an option when the original engine has suffered serious internal damage or when repairing the existing assembly is no longer practical.
Common reasons an owner may begin looking for replacement engines include:
- Internal engine damage
- Low compression
- Excessive oil consumption
- Abnormal engine noise
- Severe overheating
- Cylinder or head damage
- Internal bearing damage
- Major oil or coolant leaks
- Engine failure following mechanical damage
Before ordering a replacement, don’t rely on the phrase “2.5L Porsche engine” alone.
The M96.20 identification is important.
How to Identify the Correct 1999 Boxster Engine
There are several details that should be checked before purchasing a replacement.
01 — Model Year
Confirm that the vehicle is a 1999 Porsche Boxster.
The 1999 model uses the M96.20 2.5L engine. Porsche’s engine catalogue identifies the 1999 M96.20 production range separately from the later M96.22 2.7L engine.
02 — Model
Confirm that the vehicle is the standard Boxster, rather than a Boxster S.
The Boxster S used a different engine family and larger displacement.
03 — Engine Type
Look for:
M96.20
This is the key engine designation for the 1999 2.5L Boxster application.
04 — VIN
Check the complete VIN and vehicle documentation rather than relying on one character alone.
Important: VIN decoding can vary between databases and markets, so the complete VIN should be verified before treating a specific VIN character as definitive engine identification.
05 — Transmission
Confirm whether the vehicle uses a manual transmission or Tiptronic automatic transmission, because the engine assembly and related components may differ.
Used Porsche Engines & Motors
When searching for motors for a 1999 Boxster, you may encounter different engine assemblies that appear similar but are not necessarily interchangeable.
Used OEM Engine
A used OEM engine comes from another vehicle and can provide a practical replacement option when the correct application is available.
Long Block
A long block generally includes the major internal components and cylinder heads but may not include all external accessories.
Complete Engine Assembly
A more complete assembly may include additional components, but the exact contents depend on the particular engine.
Remanufactured Engine
A remanufactured engine has been disassembled, inspected and rebuilt according to the rebuilder’s process.
For this application, the M96.20 identification should be confirmed before considering another 986 engine as a replacement. Porsche’s catalogue distinguishes the 1999 M96.20 from the later 2.7L M96.22 and Boxster S M96.21.
Why Choose AutomartAutoparts?
Finding the right used engine or transmission can be stressful, especially when you're not sure about compatibility, availability, or where to find the right replacement. Automart Auto Parts helps make the process simple. We have helped many customers find replacement engines and transmissions for a wide range of vehicles, and our parts specialists are here to help you identify the right option for your vehicle.
With so many used engines for sale online, finding the correct replacement can be difficult. Automart Auto Parts helps make the process simpler by helping customers identify appropriate used engine applications based on their vehicle information.
With multiple warehouse locations across the state, we can help customers connect with available parts closer to their area. Our network and inventory sources allow our team to check available replacement engines and transmissions based on your vehicle's requirements.
Trusted by Customers
We've helped many customers with their replacement engine and transmission needs, providing assistance throughout the process.
Multiple Warehouse Locations
With multiple warehouse locations across the state, our network helps us serve customers in different areas and check for available parts closer to them.
Fitment Assistance
Not sure which engine or transmission you need? Our parts specialists can help verify your vehicle and part information before you move forward.
Availability & Pricing
We can check current availability and provide pricing information based on the replacement part your vehicle requires.
A Simpler Way to Find Your Replacement Part
You don't have to spend hours comparing used motors for sale and trying to determine which engine will work with your vehicle.
Tell our team your vehicle's year, make, model, engine size and VIN when available. Our parts specialists can use that information to help identify the appropriate replacement application and check available options.
Whether you need a used engine for a car, truck or SUV, starting with accurate vehicle information makes it easier to narrow down the correct replacement.
Porsche Boxster Engine Near Me
Searching for Porsche Boxster engines near me can produce many different results, but location doesn’t determine compatibility.
A nearby engine can still be the wrong engine.
For the 1999 Boxster, confirm:
2.5L + M96.20 + 986 + complete VIN/vehicle configuration
before purchasing.
If you’re unsure about your engine, send us your VIN and vehicle details.
How It Works
Finding the right replacement engine or transmission is simple. Tell us about your vehicle and our parts specialists will help you find the right replacement option.
Tell Us Your Vehicle
Provide your vehicle's year, make, model and engine or transmission information. We may also ask for your VIN to help confirm compatibility.
Tell Us What You Need
Let us know whether you're looking for a used engine, replacement engine, used transmission or replacement transmission.
We Check Availability
Our parts specialists check available inventory and supplier options to help identify a suitable replacement for your vehicle.
Get Your Quote
Once an appropriate option is identified, our team can provide available pricing and relevant part details for you to review.
FAQ
What engine does the 1999 Porsche Boxster use?
The 1999 Porsche Boxster uses the M96.20 2.5L water-cooled flat-six engine. Porsche technical documentation lists six cylinders and 2,480 cc displacement.
M96.20 Engine Details
The M96.20 is a particularly important identification point when searching for a Porsche engine for this Boxster.
Flat-Six Configuration
The six cylinders are arranged horizontally in opposing banks. This is commonly referred to as a flat-six or boxer-six engine.
DOHC Valvetrain
The engine uses four overhead camshafts, with two camshafts serving each cylinder bank.
24-Valve Design
Each cylinder has two intake and two exhaust valves, resulting in 24 valves across the six cylinders.
VarioCam
The M96.20 incorporates Porsche’s VarioCam camshaft adjustment system to alter camshaft timing according to operating conditions.
Integrated Dry-Sump Lubrication
Porsche’s technical documentation describes the M96.20 with an integrated dry-sump lubrication system. This is an important characteristic of the engine and one reason the complete engine configuration should be verified when sourcing replacement motors
2.5L Porsche Engine Performance
How many valves does the M96.20 have?
The engine has 24 valves, with four valves per cylinder. It uses DOHC architecture.
Is the 1999 Boxster M96.20 the same as the 2.7L Boxster engine?
No. The later 2.7L Boxster uses the M96.22, while the 1999 2.5L uses M96.20. Porsche's engine catalogue separates these applications by model year and engine type.
Is the M96.20 turbocharged?
No. The 2.5L M96.20 is naturally aspirated.
Explore More Engine Applications
Looking for a replacement engine for another vehicle?
Explore our vehicle-specific engine pages for information about engine specifications, fitment, VIN identification and replacement options.
