Photos would be helpful.

Al--A couple of things. Depending on when your existing garage was built, it may be deemed an existing/non conforming structure (i.e. into a setback/too close to a property line). If so, there are very distinct limits on how any rebuild involving any changes to the footprint, mass and height of the garage can be executed. Any additional roof (porte cochere) coverage = lot coverage, which must be calculated along with your existing home and garage to make sure your project abides by land use standards in your area. Depending on where you are located, I have done many projects of this nature, and I would like to consult on this project. If geographically undesirable for your needs, I would suggest that you should consult an architect in your area, due to these, and the aesthetic nature of blending new structure (porte cochere) into your existing residence. Happy Houzzing.

Mr. Yates, you're welcome.

We've just posted some photos of a recent carport project - I wonder if these would be helpful to your design discussion?