Just put on the Cobb downpipe and Injen intake w/ IC piping. Rollin with no undertray at the moment. Id rather put it on with different fastners because the stock ones are enough to drive you insane. Just worried about the new downpipe generatig enough heat to melt the plastic undertray.

 

I don't have any issues with the stock plastic undertray. Cobb's dp should fit well and clear the areas most dp lack.

 

No, you'll be fine as long as there isn't some crazy fitment issue. If you want to do something just to add to your peace of mind, heat wrap it.