Running w/o a catalytic converter as most turbo kits do means you will experience smells from the unburned fuel. Since most turbos also run a little rich, the problem can be worse.
If you have a top and a solid windshield, you'll probably get exhaust sucked over the rear deck and into the cockpit. I have a MadStad Adjustable Single windshield and the air flowing under the windshield pretty much eliminates exhaust fumes being drawn into the cockpit.* If you have an F4 windshield, contact them and see if their Gold-wing vent might help. Some folks use a wind restrictor mounted between the roll hoops to reduce the exhaust fumes being drawn into the cockpit. Adding a 2.5" Welter Performance rear exhaust is also said to reduce the exhaust smell. Welter also offers some air deflectors that mount under the Slingshot which are supposed to also help reduce exhaust smell recirculation.
* I should add that I have A Hahn Stage 2 Turbo kit with the Hahn StreetRace exhaust and I do occasionally get exhaust fumes when sitting at a red light. They're bad enough that my Wife diesn't want to ride with me anymore.