VW Cooling Part 2

Here are a few additional areas to address when it comes to cooling.

Pipes exiting the cowl in high pressure areas

On a Sonerai with short exhaust stacks, the front two pipes are in a high pressure area of the cowl. The openings around the pipes have to be big enough to allow for the cowl to be removed and attached easily. This leaves gaps that allow a significant amount of air to pass into the lower side of the cowl that disrupts cooling efficiency.

To address this issue on the first set of exhaust pipes for the Sonerai, I used a fiberglass material that is used to form the seal for a wood stove door. They were held in place with the cement that is used to hold them in place on a wood stove and then wrapped with safety wire.

Seals added to the pipes 

 These seals are placed at the exit hole for the exhaust pipe, touching the cowl to seal the area.

Seals as seen from the bottom

 To both reduce drag and eliminate the need for these seals the exhaust pipes were reworked to exit the cowl in a lower pressure area at the bottom of the cheek.

"Ram's Horn" exhaust pipes used to move the exit locations of the exhaust pipes

To further minimize the leakage around the exhaust pipe exits, aluminum plates were fabricated to prevent burning of the cowl and the exhaust pipes were cut to be flush with the exits. This also made the cowl much easier to install and remove. 

Flush cut exhaust pipes


I have seen much discussion about whether or not exhaust pipes should be cut flush with the cowl or not. Some say that it will damage or burn the cowl. I have not had any issues with using flush pipes since I have been using them in one form or another since 2007. 

The turbo exhaust system will be cut flush and trimmed with a stainless steel plate due to the higher temperatures associated with the turbocharger

More to come as time permits!