2006 wrx(should i go with a vf30?)

[rex25]

I have a 2006 subaru wrx that ive recently bought. Ive done a little work to the appearance dropped it with tein springs 2.5 in the front and 1.7 rear with rota gforces 18X8.5...but im looking to put the rest of my money into the motor to get to 300hp. I plan on getting either a cobb or invidia catted downpipe with exhaust and cobb accessport. I heard the stock intake is good to 300hp so im sticking with it. But i havent decided to stick with the stock turbo(if i can get to 300 with it?) or getting the vf30....And whats involved with a vf30 setup? and thoughts... I have a beater so i dont really drive it to work during the week, so its not my daily driver but i still want reliable

[Anub1s]

I hope it wasn't the S-tech springs, you're going to be replacing your struts in no time at all.

You have quite a bit of reading to do my friend. If you're looking for 300 WHP, you're going to want to look elsewhere for a turbo. You can likely get there with a an agressive tune and some other supporting mods, but if you want to do it easily without having to push the limits of the turbo, you're going to want to get a 20G, or HTA68. Granted, they're bigger and badder, but they both have spool characteristics of stock and you don't sacrifice much by way of drivability.

You're going to need bigger injectors (750's at least), bigger TMIC, fuel pump (Walbro 255 lph) and downpipe, to get to this goal, amongs the other things like boost gauge, wideband O2 sensor with gauge, and others.

Also, the AccessPort is fine and dandy for their OTS maps, and it also opens the door for tuners, but you could save yourself a lot of money with Open Source, but then it comes down to how serious you are about learning about your car and monitoring things.

Oh, and welcome to the site.

[devik]

Read the "First Mods" sticky at the top of this forum, it will help give you an idea of some other things that can help.

At the very least, you'll need the following:

255lph fuel pump
565cc injectors*
Bigger TMIC. Do NOT get a BOV, use the stock BPV.

Depending on the turbo you go with, there may be other considerations.

* Many people go with 650s or larger. 750s are literally a few dollars more than the 650s and worth it. You'll definitely need to get tuned specifically for these, or you'll be running way rich. AccessPort alone won't cut it.

[rex25]

Doesnt the 2006 2.5 come with the same injectors as an sti? I was told my injectors could handle a vf30 but maybe im wrong

[Anub1s]

Doesnt the 2006 2.5 come with the same injectors as an sti? I was told my injectors could handle a vf30 but maybe im wrong

Not the same injectors, per se, but they do flow the same as the STi pinks. They can support a VF series turbo, but to get to 300, you're going to be maxing out those puppies, and I'm not even certain you'll be able to get there with them.

Again if you're talking about 300WHP, not 300HP at the crank like the STi is rated.

[devik]

Again if you're talking about 300WHP, not 300HP at the crank like the STi is rated.

^^^^^

Assume you'll lose something like 15-20% of your crank horsepower through the drivetrain. 300 crank horse is pretty easy even on a 2.0l WRX on stock injectors, but 300awhp is completely different.

[rex25]

Well 300whp will prob be pushing my trans to the limit and i really dont want to invest money into that so im looking for 300 to the crank...but im thinking the vf30 might just be to much money right now so is it possible to get there with my stock turbo?

[Anub1s]

Well 300whp will prob be pushing my trans to the limit and i really dont want to invest money into that so im looking for 300 to the crank...but im thinking the vf30 might just be to much money right now so is it possible to get there with my stock turbo?

Ah, alright then, forget what I said in the first post.

Yes, you'll be quite able to get to 300HP to the crank on the stock turbo. You're looking to get about 240-250 HP to the wheels then. You're going to need a good tuner, preferably a better fuel pump for safety's sake, a down pipe, preferably a bigger TMIC, and possibly some meth injection. Speak to your tuner about your goal of 250WHP on the stock turbo and they will be able to tell you what you're going to need more than us on the forum.

[devik]

You can get 300 at the crank without a turbo upgrade, I think. Stage 2 + IC hoses + a protune should get you there. Possibly P&P the stock header.

A 2.0 WRX with the above plus the required uppipe swap will be right around 290ish with an OTS map.

[Sinister]

2006+ WRX's got the "Blue" injectors which flow about 565cc.

For a VF series turbo you don't need any bigger.

I'm at 86% IDC with my stock injectors at about 300whp.


To reach the same 300hp (at the engine) as the STi... All you really need is a downpipe, and tune. It'll be close enough. I'd suggest a Boost Control Solenoid as well.

The IC hoses thing that devik is suggesting isn't worth the money. You won't see more than a hp or two. P&P the stock exhaust manifold isn't a bad idea, but again more money than it's worth in my opinion.


Here's a cobb stage 2 dyno (not protune!):
Stage 2 Dyno

If you do the math for the parasitic drivetrain loss (at 20%) that's 277hp at the crank, and 348ftlbs of torque at the crank.

That's way more torque at the crank than the STi, and with the 3.7 final drive that's a much faster 1/4 mile time that the STi can do.

Add in the 3port BCS and a protune, and you'll be over 300whp at the crank and close to 375ftlbs at the crank

[brfatal]

The IC hoses thing that devik is suggesting isn't worth the money. You won't see more than a hp or two. P&P the stock exhaust manifold isn't a bad idea, but again more money than it's worth in my opinion.

Sinister, if you follow old threads about beginner mods, you will find that intercooler hoses are a great mod to do. You'd likely see more out of that than a turbo inlet.

You're gonna want to remove those springs you installed. That is waaaaaaaaaaaaaay too much of a drop. Your car probably rides and handles like balls and your struts will be hating you.

And no, you will want to get an intake. Just because something works at a certain power level, it's not necessarily ideal.

[Sinister]

Sinister, if you follow old threads about beginner mods, you will find that intercooler hoses are a great mod to do. You'd likely see more out of that than a turbo inlet.

In the old threads they suggested all of that stuff... intercooler hoses, inlet hoses, etc etc... because they gave you a couple horses and you didn't have to tune for them.

An inlet hose on the stock intercooler is a waste of time in my opinion because as soon as you go to a bigger turbo (like a vf), you'll change the intercooler, and you'll have to either get a different y pipe or hack the current one up with a razor blade. Yes... I have a silicon y pipe, but I got it at the same time I got my STI tmic to match up to my VF39.

I feel like $175 for a y pipe is not worth the 1-4hp you'll get out of it.

[Sinister]

^^ A short ram intake is better money spent than the y pipe IMO

[brfatal]

In the old threads they suggested all of that stuff... intercooler hoses, inlet hoses, etc etc... because they gave you a couple horses and you didn't have to tune for them.

An inlet hose on the stock intercooler is a waste of time in my opinion because as soon as you go to a bigger turbo (like a vf), you'll change the intercooler, and you'll have to either get a different y pipe or hack the current one up with a razor blade. Yes... I have a silicon y pipe, but I got it at the same time I got my STI tmic to match up to my VF39.

I feel like $175 for a y pipe is not worth the 1-4hp you'll get out of it.

You're right. I did neglect that is wanting to upgrade his turbo, where he will need a larger intercooler anyways. However, if you don't ever expect to go past stage 2 on a WRX and intend on keeping the stock TMIC, how does $110 for 5-10 hp sound?

[devik]

You're right. I did neglect that is wanting to upgrade his turbo, where he will need a larger intercooler anyways. However, if you don't ever expect to go past stage 2 on a WRX and intend on keeping the stock TMIC, how does $110 for 5-10 hp sound?

Even as low as $80-90 if you're just replacing the Y-pipe.

It will help decrease turbo lag a bit as well. Overall it's a very worthwhile mod, even though it's not a huge boost. It's certainly better than $300 for a 5-10hp boost.

My mention of the IC hoses was based on the statement that we're looking for 300hp crank, which shouldn't really require a turbo/IC swap.