10 BEST performance mods for the 2015-2021 Subaru WRX/STI

Here is our top ten list for modifications you need to do to your 2015-2021 Subaru WRX & STI. There are a lot of different ways to shave lap times, increase HP, and improve your driving experience. Follow this path and avoid wasting your money on mods that don't work!

IAG Performance PTFE Fuel Line Kit for use w/ COBB Flex Fuel Sensor:

Nostrum High Performance High Pressure Fuel Pump:

COBB Tuning Top Mount Intercooler Kit:

GrimmSpeed Front Mount Intercooler Kit WRX:

Mishimoto Oil Cooler Kit WRX:

Mishimoto Oil Cooler Kit STI:

Koyo Aluminum Racing Radiator:

Whiteline Front and Rear Sway Bar Kit w/Endlinks:

GrimmSpeed Stealthbox Intake System:

Cobb Intake:

AEM Cold Air Intake System STI:

PERRIN Performance J-Pipe with Catalyst:

Grimmspeed Downpipe:

Ohlins Road & Track Coilovers:

FactionFab F-Spec Performance Lowering Springs:

Whiteline Adjustable Lower Control Arms (Rear):

Faction Fab brake pads:

ATE Original TYP 200 DOT 4 Brake Fluid - 1L:

Brembo GT Systems 4 Piston Front Big Brake Kit Red With Slotted Rotors:

Apex Race Parts EC-7 18x9.5 5x114.3 +38mm:

Cobb Accessport:

[BaconNDCheese]

Pro tip, if you're gonna change top mount or front mount intercooler, just wait till you get the cold air intake too and just switch it all at once so you can tune it all at once.

[steelersforlife]

You should do a video on how to set up the Cobb accessport and what you need to do it

[Biirdman]

8:59 he says "2015 wrx picks up 26 and a 2015 wrx picks up 30" I think he meant sti the second time.

[chocOneOOne]

I'd swap sway bar for coilovers because you can compensate for much more than a swaybar, plus the stock ones are pretty decent.

[jerodcombs]

Would love to see the catted j-pipe install!

[alexartayet]

That silver STI ripping around Mid Ohio showing off his sick brakes is pretty cool! :P

[godsplannn]

Dope video, really loving this guy along with Kevin! 🙌🏽

[mikecrean]

Great list but I think you should have given the cost some perspective as many of us are budget conscience.
1-6 Accessport first is good, but Sway Bar, Wheels & Tires, Brakes, Catback, Coilovers, In that order as the non tune items (also if you want to auto/Rally cross, not drag). I'd say Intake next as you can get a complimentary tune if you go COBB or MAP, but sneaking in the Turbo Inlet, Charge pipe and boost controller though easy and all good is a bit misleading and why I think those should be paired with J-Pipe and/or TMIC/FMIC as a pro/e-tune will be necessary unless you only buy Cobb (and still should probably be done).
Lastly though I agree on your longevity and piece of mind call with Oil Cooler and Radiator, I also found it funny that the video showed headers but they weren't included, so lets add that to the parts stockpile (turbo inlet, boost controller, charge pipe, TMIC/FMIC, Headers, J-Pipe) before you throw them on and go get that pro-tune.

[calpsych]

Curious: what would you estimate the cost of ALL of that lace if you chose one item per each of your categories? in other words, what would be the cost of the full Monty...parts alone? parts plus labor if not installed via DIY?

[GTSCoupe]

Thanks for the tips great video. I just realized a lot of these tips for quick and easy modifications will apply to a lot of turbo charged cars. Cheers

[elbandidosti]

AOS, Turbo, Fuel pressure regulator, CF drive shaft, and a few more.

[sickntired]

Great vid
I’d say before doing the performance mods on your STI invest in a few of the longevity mods. First being an AOC, been running with the Cobb AOC for few years with no issues and it has removed the film of oil that used to live in my intercooler! Then I’d do the #4 cylinder cooling mod, the oil pickup/windage plate/oil pan mod, the brake master cylinder brace (the firewall does NOT flex anymore). Also got a performance radiator that performs outstanding. The heater is a bit cool in the winter AT IDLE only, other than that it’s perfect. Then go with the exhaust. Cat back with no time needed or full turbo back with a tune needed. “Let there be airflow” !! The factory intake is 100% the best but if you want the sound and a TINY bit of HP increase do the intake, charge pipe, turbo inlet and boost controller with a tune. All that being said. The very first thing you should buy, day one, ! Is an access port. But beware some dealers will void the warranty. Mine did not on my 2020 STI. Enjoy your awesome car.

[reloadingdragon]

Yall should make a video on your opinions on the cancelled STI

[michaelanderson]

For the Wheel/Tire option, it seems you only mentioned a Street bias. What would you recommend for more off-road worthy? I live in Minnesota. I think I would prefer to stick with a 17" wheel to get more sidewall. Nasty potholes. I owned a 2008 Subaru Legacy Limited for a few years. Never got around to modifications though.

[SirChubblesSteen]

Which ducktail spoiler is on the blue WRX?

[ranran]

For an e-30 blend on a wrx you don't need to upgrade unless you plan to do higher mixtures.

[LJV-]

good top ten
I will add one the transmision carbon fiber

[armando]

What do you guys recommend for lower control arms on a 90% track use sti? Quality/safety being #1.

[lyfewithpiglet]

There is a company in Richmond Virginia who do amazing work on Subis. National Speed Richmond

[bagelsecelle]

Always start with the exhaust and suspension, cheapest compared to rest since you need to tune them (unless ur swapping TMI with basically the same as OEM)