Aftermarket (automotive), the addition of non-factory parts, accessories and upgrades to a motor vehicle.

Once we buy a car brand new from showroom all the parts that the car has are Orginals,
In car language its called STOCK

If we upgrade with car parts that are Non-Standard or not the company orginals and are bit modified are called Aftermarkets.
Some people use the After market stuff to change the looks, some do it for the performance and some for both.

Most commonly used Aftermarket Autoparts are as follows
- Alloy Wheels (like BBS , 5-Zigen)
- Body Kits
- Head lights and Tail lights
- Bonnet Scoops
- Carbon Fibre Bonnets
- Exhaust pipe ( Either Ventilated or just normal)
- Boost Pressure Meters
- Shock absorbers ( to lower the car or increase the hieght)
- Bumper Lights
- Rear Spoilers ( Banshee etc)
- Reverese Sensors
- Turbo Chargers Aftermarket ( with good tune up can give more Killowatts than Stock turbo)
- Turbo Timers
- Super chargers
- BOV Blow Off Valves ( makes a sound when you change a shift)
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People are more than welcome to share their knowledge and understanding about the car parts