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Discussion Starter #1
Ok, I'm a noob, I admit it, but I gotta start somewhere.

The 2008 STi comes with a IHI VF48 turbo. Ok, now I understand that we can upgrade to this turbo or the AVO380 without any fuel system mods, So...
How do they relate to each other in terms of power output? Because honestly, If I can get the VF48 for less than 1/2 the price of the AVO and make the same power with a "subaru" part, then you know the rest.

Any gurus care to shed some light on this?
Thanks everyone!!
 

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Are you going for top-end or an all around better turbo?
the 380 is a nice choice because it spools faster and doesn't run out of breath like our stock turbo's. I done know enough about the STi but I have a feeling for the same price as the 380 you could get more top end out of the avo420 so unless you got the vf48 for a killer deal I can't imagine why you'd want it. Btw check out forced performances website for a much more consumer friendly price on turbo's
 

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Make sure that the VF48 that you are looking at is a ball bearing turbo... The AVO turbo is a real high quality turbo. Now many turbos are cheaper but the AVO will last a lot longer then any of them. But, do what is within your budget.
 

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Discussion Starter #6
Make sure that the VF48 that you are looking at is a ball bearing turbo... The AVO turbo is a real high quality turbo. Now many turbos are cheaper but the AVO will last a lot longer then any of them. But, do what is within your budget.
I do not mind paying for quality and the price really isn't too much of an issue as long as I am "getting what I paid for". I started looking around after I spoke with the guys at HarmanMotive and they suggested that I go with the STi's VF48 and STi factory TMIC. I was under the impression that since both the AVO and VF48 did not require any fuel system upgrades, that the power levels must be around the same.

As far as my goals: I want to go as far as the factory fuel system will let me. I built a 633rwhp/768ftlb 2003 Ford Lighting a couple years ago and went through 3 sets of Walbro fuel pumps (which equal 6 pumps). All of them just failed. I towed that Lightning home almost as many times as I drove it home, LOL. So saying I do not trust aftermarket fuel systems is an understatement.
You guys got any better suggestions than the AVO?
 

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*cough cough* forced performance *cough* cheaper than your sti turbo I'd post thelink but I haven't figured out how to do that on mi iPhone
 

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btw with the money you save buying an FP you could buy a water/meth injection kit and that will lower the duty cycle % on your injectors.
 

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with stock fuel rail and all the requirements are identical to the Avo 380. The next step up would be the 420 and I would bet you could get away with that if you did a water/meth injection( it sounds like the 420 is close to maximg out the injectors)
 

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Discussion Starter #11
I understand I can use the stock fuel system with the AVO380.
What I meant to ask was:
Which "FP" turbo should I be checking out? Also, do you know if they are a "bolt-on" application, or am I required to purchase or fabricate other parts to make it work? You are right though, the FP prices are very good.
 

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I'll be honest and say I'm not sure exactly which one to can get and still be good on factory fuel equipment my limitation when I'm looking at aftermarket turbo's is the boost range in which they operate. The "18g" likes boost in The 21-24psi range which to me sounds a little too high on stock intervals. I'm looking at the "big" 16g, good for about 325 to the wheels and operates between 18-20psi. Hope that helps.
 

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Discussion Starter #13
I'll be honest and say I'm not sure exactly which one to can get and still be good on factory fuel equipment my limitation when I'm looking at aftermarket turbo's is the boost range in which they operate. The "18g" likes boost in The 21-24psi range which to me sounds a little too high on stock intervals. I'm looking at the "big" 16g, good for about 325 to the wheels and operates between 18-20psi. Hope that helps.
That's about where I would like to be. The 16g seemed to fit the bill but I still e-mailed them about my goals and wanting to stay with the stock fuel system. Hopefully the will get back with me soon (although I am in no hurry, I only have 700 miles on the car. The wife is already afraid it's going to be another Lightning headache,LOL!!).
 

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haha how many times I must have hears my wife complain about how I'm never happy with my cars LOL.
 

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Yeah... I put on the new exhaust and my wife was not happy cause she didn't like that it was so loud... HEHE... That and I didn't tell her about it, she just noticed.
 

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So coop I guess when the two of you go anywhere it will be in the wife's Altima then huh LOL! Shouldn't be too long before I am in the same boat. But my GF wants to get into auto-X this summer so it should be all good LOL.

Seth
 

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That is cool. We still take my car a lot. But, I have not been feeling like driving lately cause I drive a lot as is, so we do take her car, but we have to watch the mileage with hers cause it is a lease.
 

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Discussion Starter #19
Yea, the first time my wife gets smoked by a kid in an EVO, STi, Mustang (hell anything!!) and the "don't touch the car" attitude is out the window.
 

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Guys,

STi turbos like VF46 will require a front mount intercooler to work on '08 WRX. The turbo outlet flanges are different so older WRX/STi turbos are not a direct fit. Intake manifolds are different. Look at the VF40 from a LegacyGT if you want to retain a Top Mount and use a Subaru turbo.

Our AVO turbos are all ball-bearing, not journal bearing like stock turbos or FP turbos. Longevity of the turbo is the biggest difference. A ball-bearing turbo is 10x stronger than journal bearing. Thus the price difference.

Just my 2 cents,

Sean S.

www.RalliTEK.com

 
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