Hi Ron, thanks for initiating contact. The key advantage of a dual exhaust is its ability to more efficiently expel exhaust gases, leading to gains in power, fuel economy, and engine cooling. However, the dual system is also more complex and costly to install compared to a single exhaust. We suggest consulting with a professional. Have a nice day.

Hi Malyvanh, This item is for the 2010 Cadillac CTS only. To look for valance and check the fitment please use our Vehicle Selector — which can be found towards the top of the homepage as well as all categories, search results, and product pages — can help verify if a part will fit your specific application. To enter your application, simply select your vehicle’s year, make, model, sub-model, and engine type and click “Go.” Once your application is selected, you’ll see a “Guaranteed to Fit” badge if the part will fit, and we recommend that you also double-check Your Vehicle Fit Details as well as the Vehicle Fitment Information table on the product page.