I live on Long Island. So there would be no need for really off road driving. I would definitely get some gravel spec coils and raise them a little higher then stock. High enough to clear most debris but low enough to take turns at high speed. My Sti wouldn't be used fight off zombies, rather to venture out and collect supplies so gas mileage wouldn't be to big of an issue. Having fuel would be the issue so you'd have to distill ethanol or else you could look at your non running response vehicle in the driveway. Tires would also be an issue. I would run street tires with an incredibly thick tread to last the longest. A brush guard would be must. A hatchback would also be a must. A grill in the hood scoop as well as the lower opening to protect from debris. and a safari rack on top with a light bar. To carry the collected supplies and light the night. (think about how dark it would be with no lights anywhere) And I don't know about you guys but NYC alone gives off enough light pollution to make seeing at night no problem here.