From 2005 to 2009, the company produced the 3.4-liter boxer Porsche M97.21 engine, which was mounted in the rear of the 987 on sophisticated versions of the Boxster S cabriolet or Cayman S coupe. Under its M97.22 index, a slightly more potent version of this power unit existed.
M97-line engines: M97.20, M97.21.
Specifications
| Production years | 2005-2009 |
| Displacement, cc | 3387 |
| Fuel system | distributed injection |
| Power output, hp | 295 |
| Torque output, Nm | 340 |
| Cylinder block | aluminum H6 |
| Block head | aluminum 24v |
| Cylinder bore, mm | 96 |
| Piston stroke, mm | 78 |
| Compression ratio | 11.1 |
| Features | no |
| Hydraulic lifters | yes |
| Timing drive | chain |
| Phase regulator | VarioCam Plus |
| Turbocharging | no |
| Recommended engine oil | 5W-40 |
| Engine oil capacity, liter | 7.75 |
| Fuel type | petrol |
| Euro standards | EURO 4 |
| Fuel consumption, L/100 km (for Porsche Cayman S 2008) — city — highway — combined |
15.3 7.8 10.6 |
| Engine lifespan, km | ~240 000 |
| Weight, kg | 191 |
The engine was installed on:
- Porsche Boxster 2 (987) in 2006 – 2009;
- Porsche Cayman 1 (987) in 2005 – 2009.
Disadvantages of the Porsche M97.21 engine
Seizures in the cylinders are the most well-known issue with the M97 family of units; these motors failed to overcome the serious issue with the intermediate shaft bearing;
Additionally, there are strict lubrication requirements that frequently cause the liners to turn;
The timing chain typically needs to be replaced after a 150,000 km run;
The engine’s cooling system, specifically the water pump, is its weak point.