Wire Mesh Grills- Radiator Protection for your Porsche

One of our most popular items for the newer generations of Porsche’s 911 are our Rennline Wire Mesh Grill Kits for the 996, 997, 991 chassis, along with their 987 and 981 brethren. For some reason Porsche decided to forgo any kind of radiator protection, mounting them right at the front of the car and leaving them exposed to the elements and road debris. With our experiences on-track and on the road, we saw the need for a custom tailored kit. Our grills install behind the front bumper but in front of the radiators to provide maximum protection while maintaining a factory fit and finish. Unlike other kits on the market, we don’t use any tape or glue, and no modification to the bumper is required. Instead our grills attach to the inexpensive, replaceable duct work that fixes to the back of the bumper, meaning reverting back to stock requires no paint matching or major body work.

Gbree's 991 Carrera S with Rennline grills, tow hook and gopro camera mount

Gbree on the Rennlist forums with his Rennline grill, tow hook and GoPro mount equipped 991


A History of Porsche and its Radiators

1996 marked the beginning of a major shift in Porsche vehicle production. The spiritual successor to the 914, the Boxster was a mid-engine roadster that slotted into the lineup below the 911, both in price and performance. Although the 993 chassis 911 had only been on the market for a year, Porsche released the Boxster which was a sign of widespread change in Porsche’s performance lineup.  Up front were two parts that foreshadowed the end to a 35 year tradition- twin radiators mounted up front with coolant pumping through them- COOLANT! And sure enough, when the 996 chassis 911 debuted in 1999 it was the first water cooled Porsche 911 ever.

Original Porsche Boxster with radiators in front

Yes, it has now been a quantifiable “while” since the original Boxster debuted

By changing to a water cooled engine, Porsche risked alienating its die hard enthusiasts but was able to thoroughly modernize the 911 power plant. This had huge benefits in terms of thermal efficiency and power potential, but offered some packaging challenges. To balance the added weight and provide optimal airflow to the now-necessary radiators, Porsche mounted either two or three radiators in the front bumper depending on options packages. Twin radiators, one on each front corner, were standard with a center radiator as optional for customers living in extremely hot climates or who planned on frequently tracking their cars. This setup has marched on, with minor revisions and redesigns, right up to today.


What Makes Rennline Grill Wire Mesh Grill Kits Superior

When we set out to create a product, there is a huge number of factors we consider. First and foremost is function- Rennline parts are designed to be used and abused either at the track or in the real world, but fit and finish, aesthetics, and a host of other design elements. For these reasons, we decided that the only way to achieve all of our primary goals with these kits was to install them behind the front bumper. This preserves the look and design that Porsche originally penned and also allows all installation hardware to be tucked out of sight, taking the OEM fit and finish to another level.

Because we are track junkies as many Porsche drivers are, we needed to ensure there would be no adverse effect on the cooling capabilities of the radiators with our grills installed. Extensive hot-weather testing ensued by setting up the shop 997 to run a number of mesh configurations and monitoring engine temps through the OBD port. We noticed surprisingly little variation during this exercise, and saw almost no temperature difference through several different setups. In the end, we chose to manufacture the grills from a webbing we found had no discernible affect on coolant temps but kept the openings small enough that they would keep all but the smallest of debris out.

Black Rennline Wire Grill

A Rennline Grill powder coated in black


Silver Rennline Wire Grill

A Rennline Grill powder coated in black


Stainless Clips for Rennline Front Grills

Some of our specialty stainless clips, fabricated in house, specifically for our grill kits


Installation Time!

So you have decided you want to protect your expensive radiators, and your engine for that matter, and you have decided you want a very OEM look. If you settle on one of our kits, there are a few basic steps you will need to perform. The first is removal of the front bumper which sounds a lot more intimidating than it really is. This process varies by generation, but a quick search for your chassis and “bumper removal guide” should easily yield photo-heavy DIY guides for those attempting this process at home. Although it can be a bit tedious finding every last clip and screw, the process itself is not hard.

Once the bumper is removed installation of the grills is a snap. Each kit will include specialized install instructions for your specific bumper, and will include all necessary hardware to complete the install. The instructions will show you how to place the grills and will lay out specific hardware locations as well. If you would like to see the process for yourself as performed on our former 997 shop car, you can see our installation video here: https://www.youtube.com/watch?v=ioegNjKr12k

After you have the grills affixed to the front bumper, installation of the bumper is the reverse of removal. The only difference is that the duct work tends to sag as you try to assemble the front bumper back onto the car. It is important to make sure these ducts fit securely into their receptacles on the bumper, so take your time and make sure to support the ducts from the bottom as this often helps alleviate the sagging problem.

And you are done! We find dealerships tend to complete installation in 2-3 hours, while a DIY garage or driveway job can last a bit longer if you have not had the experience of removing the front bumper before. Be sure to take advantage of having the front bumper off to thoroughly clean out your radiators and surrounding crevices since you are in there anyway. Many customers also take this opportunity to give their radiators a quick spray paint touch up to make them look uniform behind the grills. Many independent tests have time and time again shown that as long as the paint is applied thinly, it will not affect the thermal efficiency of the radiators.

Silver 991 GTS with black Rennline radiator grills

A 991 with the Aerokit front bumper sporting some Rennline Grills


Silver 991 GTS with Black Rennline grill in black with center radiator

This customer elected to install the center duct from a 3rd radiator car so he could use our center grill


Silver 991 GTS with Black Rennline grill in black with center radiator

To use our center grill on a car with no center radiator, you will need the retaining frame designed for cars with the same front bumper you have but equipped with a 3rd radiator


Get out and drive!

Now it’s time to get out and enjoy your newly protected 911, Boxster or Cayman without worry of road debris ending your engine’s life. Whether at the track or on the street, you should be covered no matter what the tarmac throws at you.

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