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Old 10-10-2004, 07:23 PM   #1
whiteguyblacksti
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Default Why get that small turbo like a 20G when you can go green?!?

Lots of Sti guys...people....have been upgrading their turbos lately, or at least talking about it. I have read through a lot of the threads talking about whats good, whats bad, whats the wrong decision, whats stupid, and I have gotten a bit confused with it all. Some people have bought 18G's and 20G size turbos for their STis and it seem people say that is too small, or not enough whp gains for the money, why not just go green. My thoughts are, I do want to upgrade my turbo in the future, and the green has gotten great results, but I dont want my engine to blow up! Is it ridiculous to run 18psi on a green? Is it ridiculous to run 16-17psi on a 20G? I understand the thought that the turbo can handle a lot more, but the people that buy these turbos but dont want to go over 20psi just dont want their engines to blow right? I have seen it said many times that 23-24psi will blow your engine, maybe not now, but it will, and I just dont know what to believe. I am all for getting a Green when I buy my turbo and supporting mods and running it on 21-23psi on 91 octane if my engine isnt gonna blow up after 40,000 miles, so if this is the case please tell me. Is there a better turbo to buy if you dont want to run over 20psi and risk a blown engine. (I know same psi on different turbos is a different amount of air crammed into your engine) If anyone cares to elaborate on this I would really appreciate it.
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Old 10-10-2004, 10:22 PM   #2
Invisiguard
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Quote:
Originally Posted by whiteguyblacksti
Lots of Sti guys...people....have been upgrading their turbos lately, or at least talking about it. I have read through a lot of the threads talking about whats good, whats bad, whats the wrong decision, whats stupid, and I have gotten a bit confused with it all. Some people have bought 18G's and 20G size turbos for their STis and it seem people say that is too small, or not enough whp gains for the money, why not just go green. My thoughts are, I do want to upgrade my turbo in the future, and the green has gotten great results, but I dont want my engine to blow up! Is it ridiculous to run 18psi on a green? Is it ridiculous to run 16-17psi on a 20G? I understand the thought that the turbo can handle a lot more, but the people that buy these turbos but dont want to go over 20psi just dont want their engines to blow right? I have seen it said many times that 23-24psi will blow your engine, maybe not now, but it will, and I just dont know what to believe. I am all for getting a Green when I buy my turbo and supporting mods and running it on 21-23psi on 91 octane if my engine isnt gonna blow up after 40,000 miles, so if this is the case please tell me. Is there a better turbo to buy if you dont want to run over 20psi and risk a blown engine. (I know same psi on different turbos is a different amount of air crammed into your engine) If anyone cares to elaborate on this I would really appreciate it.
first off, PSI doesnt automatically blow motors, poor tuning does

Second, I suppose as far as turbo selection, some people prefer a faster spooling turbo over a a larger slower spooling turbo and its as easy as that. A green is not the perfect turbo for every person and every application, keep in mind the majority of STI out there will live their entire lives happily off the stock VF39.
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Old 10-11-2004, 02:02 PM   #3
whiteguyblacksti
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Old 10-11-2004, 02:22 PM   #4
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Quote:
Originally Posted by Invisiguard
first off, PSI doesnt automatically blow motors, poor tuning does

Second, I suppose as far as turbo selection, some people prefer a faster spooling turbo over a a larger slower spooling turbo and its as easy as that. A green is not the perfect turbo for every person and every application, keep in mind the majority of STI out there will live their entire lives happily off the stock VF39.
Agreed on both statements. And for the second, that is especially important to understand in the above question. Understand that PSI doesn't equate to linear increase in speed. For those who want better low-end (like Auto-X types) a smaller or twin-scroll might be perfect while those who like to drag may prefer a bigger turbo that will increase power on the upper end. The whole thing boils down to where you want an increase. The Green is getting popular because it seems to be able to provide a good balance in power; which is what a lot of people who don't have a highly specific need go for, they just want 'more'.

First you will need to make sure exactly what you want out of your car before you can pick the parts to get you there.

As for reliability I am still thinking water (or alcohol) injection can go a long way to help, especially for those who only get the crappy 91 octane. You may want to look into WI to help in terms of increasing reliability.

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Old 10-11-2004, 05:17 PM   #5
Invisiguard
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one other quick point to make, dont get caught up in some peoples fixation around here to find a turbo that wont lose a single PSI at redline. Ive heard people here completely discount an otherwise great performing turbo because it didnt hold full boost out to redline, well guess what, on a street driven STI at least 95% of its life is going to be lived below 6K, hell below 5K! Dont know about you but I'd want a turbo thats going to perform its best in the range where its going to see the majority of its use IMHO
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Old 10-11-2004, 06:14 PM   #6
n2xlr8n
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To answer your question more directly...

A 20G will do well with 20 psi, a Green would just begin to enter it's "sweet spot" at that pressure. Don't discount the 20G for an every day turbo; It kicks arse.
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