How to Retain Your Cabin Heater When Installing a Performance Exhaust System

Your cabin heater and defroster will be disabled when installing most performance exhaust systems. This is because the connection between the fan shroud and the heater box is lost with the removal of the stock exhaust. To retain the use of your cabin heater and defroster, follow the simple instructions below. You may click on each image to enlarge.

This is a diagram of an engine with the original stock exhaust. Note how the heater hoses end at the rear engine tin, just at the top of the stock exhaust.

The portion circled in red on this diagram depicts the connectors that will be lost when the stock exhaust is removed. It is these lost connectors that need to be addressed by installing new fan shroud heater duct hoses. In order to accomplish this, remove the stock exhaust system, leaving the heater boxes.

Tip: The heater boxes will need to be loosened to assist in the installation of the new performance exhaust system. We recommend replacing gaskets at this time.

Once the new performance exhaust system is installed, you will need two uncut heater hoses. Follow these steps:

1. Install the new heater hoses on the fan shroud heater ducts.

2. Stretch the hoses down, bypassing the original exhaust section. Special care should be taken when routing the hoses so that it does not touch the new exhaust heater tubing. This could cause the hoses to be burned.

3. Clamp the hoses directly to the heater box intake ports.

4.In most cases, the rear engine tin will need to be modified, or replaced with a "no heater hole" style rear engine tin. Using this tin will allow the end user to drill new holes for the heater hoses allowing a better angle for the heater hoses to reach the heater boxes.

5.The manufacture states that the installation of any after-market exhaust is expected to be used to eliminate the cabin heater system. These instructions are intended to be used as an idea as to how the heaters may still be used. This is intended to be used as a theory as to how you can modify the vehicle as a custom application. Please be aware that some fabrication and creativity may be necessary to complete this task. We are happy to help in any way we can.

Please Note: Due to the heat generated by the engine, these hoses will need to be replaced from time to time. It is best to route the hoses as far from the header system as possible to minimize heat damage.