Subaru WRX Forum banner

STI mods questions please help :)

839 views 3 replies 3 participants last post by  Eldraque 
#1 ·
Hello clubWRX, I have hesitated many times to post the following questions since I am sure that it has been mentioned a lot. However, my questions are related to a specific case! And it will cover a specific scenario.
I am not sure if this is the right place to post this, but I hope so.
I am planning on buying a STI soon and after roaming around many posts, I still wonder what would be the best for me.

I have driven so many cars in my life (tuned cars and normal cars, including Nissan GT-R 2012. So I guess am not new to a lot of whp :) )but have not owned subaru and never driven one.

So, I am planning on buying 2008 STI stock and upgrade it to reach 330 - 360 whp immediately, and since I live outside the USA, a friend of mine gonna help me with everything. Therefore, after reading so many posts, I was wondering if I could do that without rebuilding the engine (pistons, short block, etc.) am I gonna be able to achieve that? I was thinking of a stage 2+ with a turbo swap and upgrading injectors to 1000 cc with a fuel pump, and I read a thread about turbo chargers in this forum as well as nasioc, and found that what I want is little bit of power and fast spool (is it correct for the mentioned desired whp?). Should I stick to COBB AP and get a protune? (Is it possible to do so?) do I need to get an aftermarket ECU? Furthermore, what would be the best turbo for me to achieve that? Is it the 20G? 18G, VF? And what would be the characteristics in terms of psi? I've heard that 22 psi is the maximum for stock pistons (is it true?) and can I put a bigger turbo with specific mods and a lower psi with the fast spool to achieve reliability? I know that my questions may sound dump, but I was hoping to get answers for that specific scenario.
Furthermore, if the mentioned whp above is impossible to reach without rebuilding the engine, what would be the maximum whp I can achieve with stock pistons?
Should I replace clutch and other parts? Or the stock clutch can handle up to 360 whp?
And one more thing which I am worried about is the temperature, in my country the temperature could reach 50 C degrees in the summer, so would I be able to drive my car in that condition? And what would be the best intercooler suited for that temperature? TMIC OR FMIC?

Thank you in advance and sorry for the many questions
 
See less See more
#2 · (Edited)
Where do you live?
What fuel do you have available to you?

What is the dyno you hope to hit your target goal on? What do stock cars typically make there?

If you're not calibrating the ECU, boost pressure should not a concern of yours. Generally speaking: boost pressure isn't what kills motors, detonation is. Additionally, you setup your boost curve based on a compressor map, not an arbitrary number.

Clutches are rated by torque, not horsepower. That said, in a typical 330-360whp setup on the EJ257, torque > hp, so the clutch needs to be a consideration.

As for TMIC vs FMIC, what is the use of the car (DD, weekend fun car, track)?
 
#3 ·
Hi there,
I live in the UAE, fuel is 91, 95, 98 oct.
As I mentioned earlier, I will make my friend who lives in the USA to take care of everything, so I was hoping that I get information on which dyno (protuner) should I visit :confused:
As for the use, I am thinking of weekend fun :)
So what do you think? Please share with me your thoughts of my goal.
Many thanks
 
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