Do I need to prep the exhaust before wrapping?

Light cleaning with a wire brush or compressed air helps the wrap grip better, but it's not mandatory. Wrap sticks to bare metal just fine. If your pipes are greasy or oily, wipe them down first.

Will 50 feet be enough for my setup?

Depends on your exhaust layout. For most single systems, you'll have wrap left over. Dual exhausts will use most or all of it. Measure your total pipe run before ordering if you're unsure.

How tight should I pull the wrap when applying it?

Wrap it snug enough that it stays in place, then secure with zip ties every 4–6 inches. Overlapping each wrap layer by about an inch keeps heat from escaping between gaps. Don't crush the material—just firm and even tension.