First Step: Exhaust Headers
The first step to get more engine performance out of your Boxster/Cayman, and arguably the most important, would be to free up the exhaust flow in the intentionally restrictive OEM exhaust system. More specifically, it’s the headers that contain the most restrictive components of the entire OEM exhaust,
not the muffler section
. Installing High Flow Sport Catalytic Converters or Catalytic Converter Bypass Race Headers is the most effective way to eliminate the key restrictive exhaust components.
Why would Porsche make a restrictive exhaust and lave performance on the table? Well, it’s because of various reasons such as environment regulations, noise guidelines, and sales/marketing. The first few versions of the Boxster and subsequently Cayman, the headers seemed to be an afterthought with regards to performance. Porsche just threw on a 3-1 tube with seemingly no account for length or flow. The OEM header collector does not optimize a free-flowing path for exhaust gases to leave the engine. The best aftermarket Porsche headers today feature equal length tubing and high velocity merge collectors to improve flow and even create exhaust scavenging. Fabspeed Motorsport utilizes high velocity cast merge collectors and equal-length T304 stainless steel C.N.C. mandrel-bent tubing for improved scavenging and overall increase in power.
On top of that, the dense OEM catalytic convertor cores are located in the header which leaves only about 8-12 inches of travel before the gases hit the second and more serious road block in the path to leave the engine. A stock catalytic convertor is a solid 600-800 cells per square inch emissions device, so tightly packed that you can not see light through them. Installing a header with a high flow catalytic converter is the best option to increase exhaust flow on a street Boxster/Cayman. Not all high flow cats are created equal though! Here at Fabspeed, we only use German-imported HJS 200 Cell Tri-metallic Sport Catalytic Converters that flow 4-5 times of the OEM converter and 93-95% of what a cat-bypass pipe without gas fumes and check engine lights. Our Sport Catalytic Converters also pass emissions everywhere except CA.
If the goal is to turn your Boxster/Cayman into a track ready weapon, do not have emissions regulations, or just want to have the highest flowing exhaust possible, you can get rid of the catalytic converters altogether and go with race headers. Fabspeed Motorsport has been engineering and manufacturing Porsche headers since the 993 Carrera and we have perfected the long tube equal length race headers for the mid-engine Boxster/Cayman models. Free-flowing headers without catalytic converters; designed for maximum power gain and exhaust flow feature F1/NASCAR style high velocity merge collector to optimize exhaust scavenging.
Step two: Air Intake
As important as it is to get exhaust out of the engine as fast as possible, it is obviously just as important to get the air in. Some will say that there are minimal gains to be had on the intake side of the Boxster/Cayman, but there are still very important intake improvements that can be made to increase horsepower, torque and throttle response. The reasoning behind the smaller performance returns of Boxster/Cayman intake upgrades, is due the already efficient Porsche OEM intake system. With stock software, the OEM intake pulls in a satisfactory amount, but it quickly becomes limiting when performance software is introduced. If your goal is to get the most engine performance out of your Boxster/Cayman, we absolutely recommend either a BMC filter or V-Flow air intake. Simply put; more air in more air out!!
Now that you have a freer flowing intake filter, the next restriction is the Porsche OEM plenum. An intake Plenum is essentially a Y-pipe that splits the intake air after it has passed through the throttle body and directs it into the intake manifold. The Porsche OEM plenum is plastic, restrictive and is not optimized for total performance. Porsche specifically does this to keep the performance down on lower end models to uphold spacing between performance levels of their different vehicles. To improve your intake plenum there is only one option, IPD. IPD has dedicated years of R&D to make the highest flowing and most efficient plenum to get as much air into the engine as possible.
Step Three: Software
Tuning the Cayman/Boxster will provide better engine performance. When tuning a naturally aspirated vehicle, you are trying to pull out as much HP and TQ as possible by adjusting fuel injection, rail pressure, fuel pump pressure, ignition timing and etc.
So with hardware you have increased the air going in and leaving the engine, now to ensure you are optimizing the increased capabilities, an ECU tune is the last but not least step in getting the most engine performance out of your Boxster/Cayman.
