Hi Mason @OffroadIllini,
I dont know your design process, but I would have created the bars as solid thrn hollowed them. If you copy your project and go back removing these features making a geometry specifically for CFD. These are the sort of things that are causing issues:
Internal frames add complexity and play little in the role of external aerodynamics:
The shell around the could be represented as a solid thus removing unnessesary spaces:
This is the sort of thing you should aim for:
See how the nose is one solid, the bars are just solid representations and the shell between the bars dont have any gaps between them and the bars. A representation like this will be very close to detailed geometry but with less computational requirments and more importantly, beter stability (it isnt having to resolve down to air flowing withing the car.
The simpler we can make this, the more time we can spend on meaningful results.
Hope this helps, I would offer to help preparing the geometry but I dont use creo.