How modifications affect each other
Vehicle modifications rarely happen in isolation. Changing one system often requires checking or readjusting another — which is exactly what inspectors and police focus on with combined modifications.
Wheels and tires
affects
- Axle geometry (toe, camber)
- Required clearance from the wheel arches and body
- ABS/ESP function when rolling circumference changes
Springs and dampers / lowered suspension
affects
- Axle geometry
- Ground clearance and the risk of scraping
- Headlight aim
- Tow hitch angle and compatibility
Spoilers and body addons
affects
- Aerodynamic stability at higher speeds
- Visibility of lights and the license plate
Steering wheel and controls
affects
- Airbag function
- Reach to controls and pedals
Tow hitch
affects
- Vehicle weight distribution
- Placement of lights and reversing sensors
Engine and power changes
affects
- Emissions and noise behavior
- Demands on the exhaust system
- Demands on the brake system at higher power
Exhaust system
affects
- The vehicle's emissions and noise behavior
If you're planning several modifications at once — say, a lowered suspension with wider wheels — also check the individual guides for each one and make sure they don't conflict before heading to inspection.