1. when deciding to do a belly pan you should look and see if you can seal it. That would mean you have clearance low enough below any exhuast.
2. when I did mine, I realized that the exhaust system was parallel with the pan so I cut the belly pan to go right up to the exhaust pipes. Then in the rear, I created a screen shield that would allow the heat to escape.
if you only have less than 1/8 of an inch, then why cover it and intentiionally create a heat problem?
for example: in my full body underbelly, IF I had enclosed the entire underbody would I have gained 1 more mpg? I really dont think so.
Proof? when I removed the center section after 1 1/2 yrs, I did not lose any mpg.
without a picture, it's hard to help you make your desicion, But I would NEVER close off the underbelly 100%.
Look at all the top of the line factory underbelly pans. I have the 2013 Audi A8 in my thread. They leave the exhaust exposed.
Again, the rear underbelly, which I used the screen material, was on the Q45 till I sold it.
here is how close the corplast is to the rear exhaust:[
you can see the exhaust on the far edge of this picture, see how close the coroplast is? how it was cut to follow the lines of the exhaust.
