Subaru WRX Forum banner

How to get a FA20 to 400WHP

38K views 6 replies 5 participants last post by  sleepertc 
#1 ·
Does anyone know or have heard of full motor builds on a DIT FA20? Besides adding a bigger intercooler which is on its way, I don't know what else to do. And I don't want to go e85 because it's not available to me.

I have 304WHP, 347WTQ....and honestly, it's just not enough.


Sent from my iPhone using Tapatalk
 
#2 ·
theres lots to do. new turbo, new j-pipe, new intake. manley does pistons and rods. IAG does built short blocks, so does MAP. seems you are not looking hard enough.

the limiting factor at the moment seems to be the direct injection. its new tech and the aftermarket is just starting to catch up now.

also seems we need a FA20 section of the forums lol.
 
#3 ·
Yeah we do need an FA section :)

But I do have a J pipe and intake.
https://youtu.be/AYsZYiKN6uo

I would like a built block, I hope more companies start making pistons and rods. I like my BorgWarner Turbo, I think it has a lot more capability in it. It's great for mid range, and I think it has even more top end but physics and heat are holding me back.


Sent from my iPhone using Tapatalk
 
#4 ·
Wiesco just released a new line of rods for the turbo market (including Subies) rated to 1000hp. They make amazing pistons and you can order a custom set if you need. As mentioed by titter, you're still on a smail, and other basic mods are still waiting. I'll recommend you part ideas but before you go pricing them out we need you to read the FAQ made years ago about going 400whp on Nasioc found here.

-ID1000cc, fuel pump, lines, rails (bigger rails flow more at same pressue, allowing inj to flow more at same IDC)
-EWG and header-back exhaust (catless isn't a necessity, more of a spool thing)
-Intake and intercooler (TMIC for spool/FMIC for another 20-30whp if you're moving)
-Bigger turbo (Blouch makes a great bolt on, the 1.5DOM XTR is designed around the 2.0L, comes single/twin scroll and is good for 380whp with 16g/18g spool) FYI bigger turbos spool later, so a 500whp turbo can spool so late you might get 1500RPMs of power if not done right. Sizing is key!
-EBCS (aids in spool and boost control)
-Forged internals/balancing

There's a starting point, do research, ask questions, post thoughts. It's your build so do it for you!
 
#5 ·
RoboTuner, I'd also point out that an FA engine isn't sold in the STi so the WRX is going to have to upgrade most of the driveline. Transmission on down. I would think it more cost effective and reliable if 400WHP is your goal to sell the FA powered WRX and get a EJ powered STi. It's engine/fueling/cooling will need much the same attention but the driveline will handle it with fewer upgrades.
 
#6 ·
Depending on your climate you may also want to look into E85 or Meth injection to help with tuning. More pressure means more heat means more knock.

I know youve got a power number in your head at the moment but have you taken any time to tighten up your suspension? Porper suspension setup really does make cars faster. Better lap times, better road handling and no additional stress on your engine/drivetrain. Ive always been a fan of Poly suspension bushings and reinforced suspension components, If you havent already i would add that gear to your list before you jump into a build motor.
 
#7 ·
Good responses from everyone, I think when I posted I had that moment where i "NEEEEEDED A MILLION HORSEPOWER"

I read the QA' sticky from Nasioc. It has great intentions.

Well so far I have the intercooler installed and the car is happy. I have raced couple modded sti's now from 3rd on and at the shift point to 4th I begin to pull away, and the car does 140MPH easily at top of 5th.

I will leave it this way till she blows, then build that IAG stage 2 or whatever "stage" block. And added cooling and supporting chassis mods like motor mounts and suspension bushings. I don't plan to ever lower the car, or go low pro tires. I did that years back and it's annoying daily.
300/347 is quick but it still very much feels like a normal daily car.

Sorry for another "head in the clouds" post, sometimes you just need someone else to talk to about your dreams of driving a "race car" [emoji23]. The end.


Sent from my iPhone using Tapatalk
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top