How much tire clearance do these flares add?

Circuit-style flares provide a modest increase to your effective fender opening. Measure your current tire sidewall-to-fender gap, then verify that your wheel and tire combination will have adequate clearance before installation. Wider tire sidewalls may require you to confirm fitment with your specific setup.

Will these work with larger wheel and offset combinations?

The Circuit design accommodates a range of wheel sizes and offsets common to the platform. Measure your wheel diameter and offset against your current fender opening, then compare to the flare depth. If you're running non-standard sizing, verify the fitment by comparing your wheel specs to the OEM fender opening dimensions.

Do these require drilling, or do they use factory holes?

These flares are designed to integrate with factory mounting points. Inspect your vehicle's OEM fender attachment locations before assembly to confirm the mounting method and fastener type. No additional drilling should be necessary if holes align with your existing hardware.