Recommended Parts for a 996 Turbo and Turbo S, Why? VRTuned.com August 21, 2009 Tuning Tech The ECU flash on a Porsche 996 Turbo is without a doubt the best bang for the buck. However without certain modifications, you will not realize the full potential of the vehicle. On both the Porsche 996 Turbo and Turbo S, it is important to first change out the stock diverter valves. The factory Bosch valves are a diaphram design which the internal rubber piece can tear under high boost pressure. Also these stock valves tend to lose boost pressure on flashed cars. Aftermarket diverter valves use a piston and spring design. The spring is stiffer then the OEM pressure to ensure that with the higher boost readings of a flashed car, you will not lose boost pressure. Both cars feature restrictive exhaust systems. You can run the stock exhaust but may not realize the full power gains unless you have an aftermarket system. The stock exhaust is like a bottleneck for the turbos. Turbos perform best with no backpressure or restriction, however your car would be incredibly loud. On a stock 996 Turbo, you will go from about .6-.7bar to 1.0bar of boost. On a Turbo S X50, you will go from .8-.9bar to 1.1bar of boost. However with a stock exhaust, this can rob you of about .1bar of boost which can equate to alot of power at the wheels. The free flowing design of an aftermarket exhaust will help your turbos breathe better and get you the full power gain of your VRTuned ECU flash. For those that are afraid of emissions or check engine lights from high flow cats, VRTuned has taken this into account. On all cars, VRTuned raises the O2 limits so they are not triggered by the additional heat passing by the O2 sensors. Most aftermarket exhausts are 100cell so not an issue. However when it comes to emissions time, we generally recommend flashing back to the stock map. The final recommendation is to have a good clean air filter on your car. The stock airbox works great for cars up to 700hp. So we recommend just swapping out the stock paper filter for a good K&N. This K&N has been tested on numerous cars to add about 5-6hp and last much longer then a paper system. Leave a Reply Cancel ReplyYou must be logged in to post a comment.