Many people have inquired into whether the Turbo S auxiliary oil cooler (or any other brand for that matter) can be installed as a DIY project. Well, if I can do it, just about anyone can. Below is the Turbo S Aux Oil Cooler kit as ordered from Gert at www.carnewal.com. There are several online vendors that sell this kit. This is the OEM oil cooler that Porsche used on the 993 Twin Turbo S. Because of this, it fits very nicely into the 993TT and I would assume any wide body 993. This is also the auxiliary oil cooler used by Andial on all of their high HP 993TT upgrades (at least per their rennlist posts).

Many people prefer larger auxiliary oil coolers, such as the Cargraphics unit below, as they provide even more cooling capacity. The downside to these units is that they will fully block your AC condenser, thereby limiting your AC’s effectiveness. In any event, I believe these instructions should apply to the larger oil coolers as well.

Step 1:

Jack up the front of the car and put it on jack stands. See http://p-car.com/diy/jack/ for instructions on this step.

Step 2:

Remove both front tires and then remove the front bumper cover. See http://p-car.com/diy/bumper/ for detailed instructions.

Step 3:

In this step you will replace the oil cooler vent cover with the new cover that allows the new oil lines to be run from the existing cooler to the auxiliary cooler. 
 

This “vent cover” (I am not sure what the actual part is called) sits on top of the oil cooler and helps to direct the air coming in the front air duct through the oil cooler. Here is a picture looking at this from the front of the car.

Once you have the bumper cover and wheels off you will have easy access to the oil cooler, which is located in front of the passenger side wheel well.

The first thing I did was to remove the rear vent cover so that I had better access to the oil cooler. Here is the same area with that panel removed.

Once this rear vent cover was removed, I then reached in and removed the screws holding the upper vent cover in place. At this point there are only a few bolts holding the oil cooler to its mounting bracket, so I removed these as well. This enabled me to have better access to the oil line connections later. I then went ahead and attached the new upper vent cover (it attached in all the same places as the original cover). I set the new oil lines into the new vent opening so that I felt like I was making some progress. With steps 1 –3 done, I think I took a long break. 

Step 4:

In this step, you will you will remove the temperature sensor bracket from the bumper. These sensors are located on the driver’s side of the front bumper as noted in the photo below.
 

In order to move these sensors, you need to drill out the 2 rivets that hold them in place. The brackets sits on top of the bumper, so I drilled the rivets out from the bottom. Once the rivets are removed the bracket and sensors can be set aside while you work on step 5.

Step 5:

It is now time to install the auxiliary oil cooler bracket and oil cooler. In order to install the bracket it is necessary to drill 2 holes in the bumper to match the bolts provided. Optimally, you will position the bracket so that the oil cooler sits squarely in the bumper duct. Once this bracket is attached, connect the auxiliary oil cooler to the bracket using the nuts and bolts provided. 
 

Step 6:

Reattach the temperature sensor bracket as far as possible to the left. Simply mark new holes, drill them out and reattached the bracket with a rivet gun. Once the bracket is in place, be sure to plug the sensors back in. 
 

Step 7:

It is now time to install the oil line brackets. This requires that you drill 2 holes in the bumper lip as shown below. Note that at this point I have dry fitted the oil lines to the auxiliary cooler. This is just so that I can make sure everything fits correctly and I can attach the oil line brackets. The oil lines are the last step.
 

Step 8:

It is now time to plumb in the new lines. I put a box under the oil cooler to catch any oil, but very little dripped out. I also placed the ends of the auxiliary lines in a bucket for the same reason.

Remember from Step 3 that the main oil cooler is hanging free. Disconnect the rear facing oil line. I used a large crescent wrench and an open-end box wrench to disconnect the line (you need 2 wrenches – one for the female oil line connecter and one for the male oil cooler connecter). Once this line is free, you can attach the curved auxiliary line to the main oil cooler.

Please Note: the new oil lines come with plastic plugs in them. You need to remove these plugs before final attachment or the oil will not flow resulting in serious engine damage.

Now take the line that was previously attached to the main cooler and mate it with the other line going to the auxiliary cooler. Make sure these connections are nice and tight.

Now attach the other ends of the lines to the auxiliary cooler, being sure to remove the plastic plugs.
 
 
 

At this point, you auxiliary cooler is attached. Replace all the bolts and nuts to reattach the main cooler to the fender well. Then check all the oil hose fittings once again. I recommend running the car for a bit to check for any oil leaks. If all looks good, replace the rear vent cover by the main oil cooler and move on to step 9.

Step 9:

Place the bumper cover back on the car to see how the oil cooler fits. The cooler should be centered inside the air vent and the oil lines should not interfere with the bumper cover fitment. If fit is not perfect, remove the bumper cover and reposition the cooler and/or oil line brackets as necessary. These brackets can be easily bent or otherwise tweaked for minor adjustments. Once you are satisfied, reverse Steps 1 and 2. Note that you should check your oil level once you are done as some oil will need to be added to compensate for the new lines and cooler. I needed to add about half a quart.