Spoiler vs Wing: How to Choose a Rear Wing for Street and Track

People use the words spoiler and wing as if they meant the same part. They do not. One manages the air that is already flowing over your car, the other creates a force of its own. This guide explains the difference, when each one actually works, and how to pick the right rear aero for the way you drive.

The short answer

A spoiler sits on the trunk lid and spoils the air as it leaves the body. It reduces rear lift and drag a little and changes how the car looks more than how it drives. A wing stands up in clean air above the body and works like an upside down airplane wing. It pushes the rear tires into the road, which adds grip in fast corners and under braking, and it also adds drag.

If your car lives on the street, a spoiler is usually all you need. If you run track days, time attack or autocross, an adjustable wing is the part that makes a measurable difference.

What a spoiler does

As air flows over the roof and down the rear window, it tends to stay attached to the body and creates a low pressure area that lifts the rear of the car. A spoiler is a lip or a small blade at the trailing edge of the trunk that breaks that flow. The result is less lift and a slightly cleaner wake behind the car.

Common types are the lip spoiler, a thin strip that follows the edge of the trunk, and the ducktail, a taller kicked up shape inspired by classic Porsche and muscle car designs. Both are easy to install, usually with 3M tape or a few bolts, and both keep the factory look intact.

What a wing does

A wing has a real airfoil profile. Air moving over its curved underside speeds up and the pressure drops, so the wing is pulled down toward the road. That downward force is called downforce, and it lets the rear tires carry more grip than their share of the car's weight alone would give them.

That is why a wing does very little in a parking lot or in city traffic and a lot on a fast sweeper at the track. It is also why a wing costs fuel and top speed: the same physics that creates downforce creates drag.

Rear aero options compared

Trunk mount or chassis mount

A trunk mounted wing bolts through the trunk lid. It is the simplest install and works well for street cars and moderate track use. The limit is the trunk itself: the force goes through the lid, its hinges and the struts, which were never designed for it. Good kits add reinforcement plates under the lid to spread the load.

A chassis mounted wing uses uprights that pass through the trunk and bolt to the car's structure. The trunk no longer carries the load, so the wing stays stable at high speed. This is the standard for dedicated track cars and the reason many race series require it.

Angle of attack, gurney flaps and endplates

The angle of attack is the tilt of the wing relative to the airflow. More angle gives more downforce and more drag, up to the point where the air separates from the underside and the wing stalls. Adjustable wings let you start with a low setting on the street and add angle for the track.

A gurney flap is a small vertical lip along the trailing edge. It adds downforce at a given angle for a small increase in drag, which makes it a cheap way to tune a wing. Endplates are the vertical plates at each end. They stop high pressure air on top from spilling around the tips and keep the wing working across its full span.

Balance the car, front to rear

A big wing on its own can make a car feel stable in fast corners but push wide at the front, because only the rear axle gained grip. Serious builds pair the wing with front aero such as a splitter or canards so the balance stays close to what the chassis was designed for. Start small at the rear, add front aero, and adjust the wing angle until the car feels neutral again.

Materials

Carbon fiber is the reference material for wings because it is light and very stiff, so the profile keeps its shape under load. Fiberglass and ABS are cheaper and are common for spoilers, where loads are low. Whatever the material, check that the mounting hardware and reinforcement are included, because that is where cheap wings usually fail.

How to choose a rear wing

1. Be honest about how you drive. Street only, occasional track days, or a dedicated track car. This decides between a spoiler, a trunk mount wing and a chassis mount wing.
2. Prefer a car specific kit. Mounts made for your model fit correctly and put the wing at a sensible height and angle.
3. Check your trunk. Spoilers that use factory mounting points are easiest. Wings normally need holes in the lid, so plan for that.
4. Look for adjustability. An adjustable angle lets one wing work on the street and at the track.
5. Plan the front. If you add real rear downforce, plan a splitter or canards for balance.
6. Check your local rules. Size, overhang and sharp edges are regulated differently from state to state, and track organizers have their own rules.

Wings we carry

We carry the APR Performance range of carbon fiber adjustable wings, including car specific kits for the Ford Mustang, BMW 4 Series and 2 Series, Mazda MX-5 Miata and Honda S2000, and the universal GTC-200 for custom builds. APR wings are built to order, and we confirm the delivery date by email right after you order.

Common questions

What is the difference between a spoiler and a wing?

A spoiler disrupts the airflow at the edge of the trunk to reduce lift. A wing is an airfoil that sits in clean air and creates downforce. A wing gives much more grip at speed but also adds drag.

Does a rear wing do anything on the street?

Very little at normal road speeds. Downforce grows with the square of speed, so the effect becomes noticeable on fast roads and at the track.

Is a trunk mounted wing safe?

For street use and moderate track use, yes, when it is installed with the supplied reinforcement plates. For a dedicated track car with high downforce, a chassis mounted wing is the better choice.

What is a gurney flap?

A small vertical strip along the trailing edge of a wing. It increases downforce at the same angle for a small increase in drag.

Do I need front aero if I add a wing?

On the street, not necessarily. On the track, a large wing without front aero can cause understeer at speed, so most builds add a splitter or canards.

Will a wing fit my car without drilling?

Some spoilers fit without drilling. Most wings need holes in the trunk lid for the uprights. Check the installation notes on the product page or ask us before you order.

Find the right wing for your car

Add your car to My Garage and product pages will show whether a part matches it. Not sure which wing or mount fits? Send us your VIN and a real person will check it for you.

This article is general information, not installation advice. Aero parts change how a car handles at speed. Use a qualified installer and follow the instructions supplied with the parts.