Anyone know of the most reliable and best way for the '06 WRX to make STI power?

Swap on sti intercooler, turbo, injectors, and ecu.

Or just add a downpipe and get some engine management for your car.

Your pretty much there with an 06 wrx... Swap turbos and tune that biatch!

But dont break your tranny w/ all that power, mmk?

id say turbo-back exhaust and an accesport

most RELIABLE and BEST way would be to swap out the motor with an STi 2.5 then get an STi transmission to make it really reliable andyou will be set. :rolleyes:

yeah, just swapping the turbo and getting a tune isnt that easy with the 06's, higher compression, diff internals all make a big difference.

sucks for all the 06 owners that they pulled the STi block after the04 and 05 OBXT, FXT and Baja XT models.

yeah, just swapping the turbo and getting a tune isnt that easy with the 06's, higher compression, diff internals all make a big difference.

Not so much.

The compression difference is marginal. It isn't like you need to run 30 PSI of boost to hit STI power levels or something. An internally stock 06 WRX motor won't hold up to 450 WHP like an STI would, but that's not what we are talking about here. We are talking about going from 230 at the crank (250, really) to 300. Not exactly a high drama proposition. A Stage 2 06 WRX is halfway there already.

You don't need to replace the fuel pump or injectors on the 06 WRX to make STI+ power levels reliably. This is a big positive for the 06 WRX, no need for a fuel pump/injector swap unless you are trying to make really crazy power. Somebody from Cobb Tuning commented on this recently.

So that pretty much leaves a new turbo and ECU tune. Your real limiting factor with the 06 WRX isn't the motor, but the rest of the drivetrain.

To answer the question directly, you need a turbo that flows like (or better than) the STI turbo, and an appropriate tune so the engine can use it. The STI intercooler and a freer-flowing exhaust would be a good idea, too.

If by STI power you mean stock STI power then nothing more then TBE and a custom tune. An 05 FXT can hit stock STI power levels with just the TBE and custom tune. I would recommend a larger intercooler however as that will help you run more boost. It's been stated that the td04 on the 2.5L basically tops out at 13psi before it becomes a hairdryer. The larger top mount will help with that and allow you to possibly hit 15psi.

NAAWS Yo! Neon, Lambo doors and some tizite vinyl stickers too. 500whp to prob :)

+1 omGEEESH!! nAwz pWnZ y00!!!!

my car noses ahead of a stock STi every time
TurboXS UTEC stage 2
Helix turboback
Turboxs FMIC

Wow, good discussion here. I'm thinking about getting the 06 WRX and was wondering it's power possibilities as well since it has the 2.5L motor now and all.

J

Also, how much are we looking at with a Stage 2 and ECU stuff? What about the tranny? What needs to be modified there?

An internally stock 06 WRX motor won't hold up to 450 WHP like an STI would
:rolleyes: And you know this how? The only difference is the pistons to bring the CR back down because of the smaller WRX chambers.

Are you in Tennessee?

Bob-E

:rolleyes: And you know this how? The only difference is the pistons to bring the CR back down because of the smaller WRX chambers.
well, it won't. Someone already blew a wrx motor. Do a search, I am too lazy :lol:

Anyway, cobb is working on a stage 3 for the WRX which will include a new intercooler and turbo. Should be fast, the limitation will be the tranny. There are some Legacy Gt's out there running big power that haven't had any tranny problems, and it's essentially the same tranny from what I understand.

well, it won't. Someone already blew a wrx motor. Do a search, I am too lazy :lol:
People have blown STi motors too. You can pop a stock one with a bad tune.

People have blown STi motors too. You can pop a stock one with a bad tune.


I agree, but it was a part that was NOT similar between the STi and the WRX. It was a piston I believe. Anyway, I am not disagreeing with you. I know that it's not proven yet. But, it's more than suspicious that one of the part number discrepancies between the STi and the WRX powerplant was the piece that failed on the modded 06 WRX. Just food for thought I guess.

If by STI power you mean stock STI power then nothing more then TBE and a custom tune. An 05 FXT can hit stock STI power levels with just the TBE and custom tune. I would recommend a larger intercooler however as that will help you run more boost. It's been stated that the td04 on the 2.5L basically tops out at 13psi before it becomes a hairdryer. The larger top mount will help with that and allow you to possibly hit 15psi.

you mean the td04 on the rex right? cause I'm hittin 19 psi on pump on my deadbolt vf39..and its powerband runs all the way to 6400 rpm then tapers off to 17 psi. 303awhp/313 wtq. But I do have a good tune and e.m. Also a boost controller. We'll see what a stock bottom end can take...over the winter I'm upgrading the turbo, injectors,fmic...etc. We'll see if it can take 500hp at the crank...I've seen it done...but for how long? Time will tell... Peace

I agree, but it was a part that was NOT similar between the STi and the WRX. It was a piston I believe. Anyway, I am not disagreeing with you. I know that it's not proven yet. But, it's more than suspicious that one of the part number discrepancies between the STi and the WRX powerplant was the piece that failed on the modded 06 WRX. Just food for thought I guess.

It was also at something like 450 WHP, not the 300 crank HP we are talking about matching here. Talk about apples and oranges! :lol:

Blows up at 450 WHP != blows up at maybe 250 WHP.

you mean the td04 on the rex right? cause I'm hittin 19 psi on pump on my deadbolt vf39..and its powerband runs all the way to 6400 rpm then tapers off to 17 psi. 303awhp/313 wtq. But I do have a good tune and e.m. Also a boost controller. We'll see what a stock bottom end can take...over the winter I'm upgrading the turbo, injectors,fmic...etc. We'll see if it can take 500hp at the crank...I've seen it done...but for how long? Time will tell... Peace

Yes a WRX with the stock td04 on a 2.5L should be able to match factory STI power levels. In reality though it probably would be faster since the tuned WRX should have a better power band and delivery then just the peak numbers of the stock STI.

I've got an '04 WRX with a turboxs full exhaust, uppipe, intake, fuel pump, UTEC, by-pass-valve, and tuned with 16.5 psi, and it will run with a stock STi. But as much fun as my car is to drive, I always wonder what an STi would feel like with the same mods:)

Anyway, I think as long as you have a good engine management system, with a good tune, you should have a safe and reliable car. Just don't get too crazy with big turbos, you might hurt the car in the long run, but I'm no mechanic.

The compression ratio is the only difference between the 06 STI and 06 WRX shortblock. All the part numbers except for the pistons are identical. The piston in the WRX are still Hypereutectic like the STI, they have just changed the crown for higher compression. With proper tuning, you should be able to make as much power out of the block as you can with the STI, with less boost to do it. If CR is a concern to you, then you could drop the compression about 2 tenths by using the thicker headgaskets from the Phase I 2.5.