Turbo RS Heat Extraction Vents for Porsche 944 Turbo (951/952) and S2 Models

The key problem: Overheating issues encountered on Porsche Transaxle models

The Porsche transaxle models are notorious for the high temperatures building up in their engine bay. This problem originally was recognized with the first series of the 924 Turbo where the heat issue led to a short lifetime of some engine components, in particular the turbocharger.

Also later front-engined models suffered from high temperatures, everyone who has opened a bonnet of a 924 turbo or a 951 after having pushed the car was astonished by the heat that has built up in the engine bay during driving. This problem aggravates if the engine has been modified and/or the car is being used as a trackday vehicle or race car.

The NACA air intake from the 924 Turbo is a popular upgrade for modified 951’s but it did not convince us from a conceptual perspective, for the following reasons. The approach of forcing more air into the engine bay via the bonnet – the top of the engine bay – may cool down the interior temperature but is rather inefficient from an aerodynamic point of view as it doesn't solve the problem of getting the hot air out of the engine bay. Another disfavour is that – installed on a 951 – it only cools down the right half of the engine bay (header) and not the turbocharger's side which also heats up considerably.

The problem solution - Heat Extraction Vents

As we did not want to compromise, we started to look for another solution which concentrates more on getting the hot air out of the engine bay and therewith lowers the temperature instead of compressing more air via the upper side of the bonnet into the engine bay also producing lift at higher speeds.

Our approach is combinable with upgraded or additional air inlets installed on the front of the car so that both, supply and effluent of air can be considerably improved and a sufficient flow-through achieved. A basic rule of aerodynamics says that the profile of the outlet area has to be dimensioned twice the profile of the inlet area in order to achieve efficient airflow. When applying this rule to the 951, this leads to the result that the air outlets have to be dimensioned quite large:

The air outlets offered by RSR9 are a simple, systematic and pragmatic solution for the above problem and also convince from an aesthetic perspective as they perfectly flow with the timeless design of the 951. The design of this performance upgrade has been specifically matched to the styling of the 951, it incorporates the two folds that run alongside the bonnet and the shape of the frame (from a top view perfectly) matches with the curvy fenders of the 951 / 944 / 924 Carrera GT. The air outlets are manufactured from FRP (Fibre Reinforced Plastic) and coated with high-quality white gelcoat on the top. They are 445mm long and 250mm wide, once installed they reach 9mm into the interior of the hood and the frame stands up from the surface of the bonnet approx. 2mms. One air outlet weighs approx 300g.

Product installation:

The area of the bonnet where the air outlets will be fitted in has to be cut out with a cut-off wheel (this works fine with a DREMEL tool or similar). After the sheet of iron has been cut out, the frame of the air outlet has to be planed so that it perfectly sits / fits on the bonnet and the 7 outlets per vent have to be cut out (the vents are delivered in solid / closed version). Then it is time to filler and sand the outlet (and paint it if the entire bonnet shall not be painted together with the new air outlets).

Later the air outlet can be glued to the bonnet using 3M adhesive for vehicle body parts (or similar) and small G-clamps to ensure proper fitment. Installation can easily be done by a person with average DIY capabilities.

The price quoted is per pair.

Production lead time (if not in stock) is approx. 10 working days from payment.