2015-2021 Subaru WRX/STI V6 Diffuser
AFD-VA-AL-DIFF-V6-GBK
$ 399.99
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Description
WRX Rear Diffuser, STI Rear Diffuser
Model: 2015-2021 SUBARU WRX/STI REAR DIFFUSER V6
Fitment: 2015-2021 SUBARU WRX/STI
- Type: Subaru WRX body kit, STI Body Kit
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Made from Aerospace Lightweight ALUMINUM no ABS PLASTIC!!!!
- Comes fully CNC'd and professionally powder coated.
- Comes pre-drilled
- Fitment Guaranteed
- Hardware included
- Professional install highly recommended
Made in USA
Proudly manufactured in the United States using high-grade materials and expert craftsmanship.
Production Lead Time
CNC items are made to order and have raw materials allocated to production once the order is placed. For concerns regarding current lead times, please review the CNC Products section in our Terms & Conditions.
A rear diffuser is an automotive aerodynamic modification typically found mounted on the vehicle’s underbody located at the rear of the car, underneath the rear bumper. As a vehicle is in motion, air flowing in the underbody is typically at high-speed and has low-pressure. The design and purpose of a diffuser are to help reduce drag and to create downforce by facilitating the airflow underneath the vehicle’s underbody. A diffuser is used to increase the air volume along its full length, thus creating a void that must be filled by air. This in turn creates a Venturi effect, meaning the air flow is accelerated at the beginning of the diffuser creating a low pressure, thus creating downforce. As the air travels along the full length of the diffuser, the high-velocity air is eased back into standard velocity matching the ambient speed at the rear of the vehicle reducing overall drag. With the addition of vertical “fins” attached to the diffuser, this helps to optimize the diffusers efficiency by ensuring that all air drawn into the diffuser is from the underbody and not from the upper body surfaces. A diffuser can be further tune-up with the addition of a front splitter to help mediate the underbody’s airflow.
Fitment & Specs
Use the vehicle finder to verify compatibility for your specific make, model and year.
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01 / Configurator
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OWNER FEEDBACK
Real Builds. Real Results.
Verified feedback from enthusiasts who installed, drove, and lived with this product.
K
Shipping was prompt. There was initially a mistake with the order, but they took care of it without a hassle. I appreciated that. Once I received the item, installation was a breeze. The brackets they use make it simple. The piece looks subtle and add a nice touch to the rear end.
E
Item arrived with a small dent/bend, but my local metal shop was able to finesse it out.I asked for the piece to be raw metal and AFD delivered on that request. Got it powder coated in illusion blueberry, it’s a little darker than WRB but overall I am satisfied.Install was easy. I would have given it 5 stars if it didn’t have the dent/bend.
E
Very sturdy, and a very easy install, highly recommend!
D
Just installed this weekend. Straight forward design and installation. Great fit and form.
D
Just installed this weekend. Straight forward design and installation. Great fit and form.
C
Called up Aeroflow with a ton of questions, they talked to me for like 15 minutes and helped me decide on the V6 and I’m super happy that I did shipping took 2-3 days. Install took me 15 minutes all necessary hardware was provided. There were a couple areas on the diffuser where the paint wasn’t that great but let’s be honest these thing are under the car and get dinged up. Super happy with my purchase.
K
Shipping was prompt. There was initially a mistake with the order, but they took care of it without a hassle. I appreciated that. Once I received the item, installation was a breeze. The brackets they use make it simple. The piece looks subtle and add a nice touch to the rear end.
K
So the diffuser looks amazing and is very good quality no complaints there at all. Only suggestion would be is to post a video or link instructions with purchase it was a little trouble to figure out where the brackets went in😅
N
Fairly simple install. All hardware required was included! Smaller hands would be ideal but doable with grown man hands. Looks super sweet once installed.
N
Fairly simple install. All hardware required was included! Smaller hands would be ideal but doable with grown man hands. Looks super sweet once installed.
L
Excellent quality, easy install (1 hour) looks fabulous.
L
Excellent quality, easy install (1 hour) looks fabulous.
P
I stayed away from aftermarket rear diffusers for a while because most of them are really obnoxious in terms of how they look relative to the rest of the STI's rear. This version of AeroFlow Dynamics's rear diffuser is absolutely perfect in that it actually is functional in terms of producing down force and smoothening air flow. However, it does this whilst complementing the existing OEM of the rear bumper. The mounting solution is great too, no need for any drilling!I personally used some loctite for the bolts attaching the diffuser to the brackets and it's held firm after countless driving tests in various conditions. You could get some nuts if you want even more peace of mind, but they're likely not necessary.
P
I stayed away from aftermarket rear diffusers for a while because most of them are really obnoxious in terms of how they look relative to the rest of the STI's rear. This version of AeroFlow Dynamics's rear diffuser is absolutely perfect in that it actually is functional in terms of producing down force and smoothening air flow. However, it does this whilst complementing the existing OEM of the rear bumper. The mounting solution is great too, no need for any drilling!
I personally used some loctite for the bolts attaching the diffuser to the brackets and it's held firm after countless driving tests in various conditions. You could get some nuts if you want even more peace of mind, but they're likely not necessary.
P
This diffuser is perfect if you’re wanting a more subtle, but still aggressive look. Installation is easy and the product is top notch. Looks great paired with my V3 rear spats!
P
This diffuser is perfect if you’re wanting a more subtle, but still aggressive look. Installation is easy and the product is top notch. Looks great paired with my V3 rear spats!
P
I love how this diffuser is subtle and aggressive. Installation was easy and the price is amazing. Thank you Aeroflowdynamics!
K
Hands down the best quality diffuser ever! I had another companies diffuser which was made out of plastic. Aeroflow's Powdercoated alum material is top-notch and super strong! Highly recommend it if you are in the market for a good diffuser.
