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Old 08-31-2014, 12:25 AM   #26
Scooby Specialist
Member#: 344329
Join Date: Jan 2013
Location: Summit County
2008 Wrx, 6mt


I have the 16gxt-r 8cm on my 2.5

(I'm at 9.2k', so boost threshold was a major issue for me)
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Old 08-31-2014, 01:50 PM   #27
Scooby Specialist
Member#: 92011
Join Date: Jul 2005
Chapter/Region: TXIC
Location: ATX
02 EJ207 STi HTA68
05 EJ257 Baja 18G-XT


How do you like that 16GXT-R point78?

I almost went with that turbo myself, but curious to hear what your real-world reviews are like for future consideration.
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Old 08-31-2014, 06:08 PM   #28
Back Road Runner
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Member#: 60082
Join Date: Apr 2004
Chapter/Region: MWSOC
Location: Minnesota
2004 Forester STI


You'll have to nail down where you want the torque band. Expect around 3k-4k torque bandwidth with any turbo. Then ask yourself where you want that 3k-4k torque peak to be. For a daily driver, I would expect you to wasn't that low, like 2k to 5k, something like a 19T, VF, or 16G. Bigger starts shifting that torque band higher. On the upper end we have 20G and GT30 based turbos were the upper end of that torque band reaches to 7k or a little higher. The original discussion started around the daily driver side, so small is what's ideal. In my eyes, this is the 19T, VF, 16G range of products. It we're talking new GTX turbos, this would include the GTX2863 which is like the 16G. I have a larger GTX2867 in my car replacing my previous 18G 7cm^2. My bro's also run a 19T and VF35 and is now on an 18G 8cm^2. The only thing I haven't run that I would have liked to its a big 16G. I think a big 16G is a better choice than the 18G. The compressor map of both indicate nearly the same top end flow (big 16G vs 18G), but the low end won't have the surge issue seen on the 18G when running the small 7cm^2 hotside. The GTX2867 spools about the same as the 18G but has more top end.

I like this progress.
19T ==> big 16G ==> GTX2867 ==> GTX3071

The 19T is the fastest and nothing beats it for bottom end spool or dynamics. The big 16G is a good trade off, a little of the bottom end spool and a bit added to the top end. I think the trade off is really more gain than loss. The GTX2867 is an excellent size product for stock range redline. It'll let you make full boost to redline and retain as much spool up, dynamics, and surgeless operation as possible. The GTX3071 will extend past the GTX2867 and suit cars with extended redline.

For a car geared for stock putzing, I'd happily take the 19T and zoom around with that. You'll still have mid 200whp and nothing will beat it for spool or dynamics. In fact, if you tweak the throttle mapping, you can pretty much make the turbo disappear. It's fast enough where you can make it so you pretty much can't notice it. If I wanted some HP gains, the big 16G I'd a great pick. I wouldn't really grab an 18G instead. My car came with an 18G installed, but if I was researching and choosing, I'd go with a big 16G instead. The flow difference is virtually nothing, and there's more low end function (read no surge) and less weight. Go look at the 18G and big 16G compressor maps. You'll be hard-pressed to ever buy an 18G. You can pair it with a 7cm^2 hotside and never see surge, plus it's within a couple lb/min of the 18G for peak flow. It's just a little bit better and pretty much the ideal compressor to pair with a 7cm^2 hotside and for a car that's not aiming for 21psi at redline.

I'd be curious of the big 16G vs GTX2863, but I don't know if anyone's really dynoed one. Steamspeed was pushing GTX2867s and GTX3071s, not really the smaller GTX2863. Again, compare compressor maps. They're quite close. I wish Mitsubishi maps were available for the new billet 16GTX, 18GTX, and 20GTX, as it's kind of unfair to compare the new Garretts to the old Mitsubishis. No data, no conclusions. That's a shame, because I have a hard time suggesting one not knowing what the compressor is capable of. I can look at old compressor maps, but the new compressors are physically different. I'd really enjoy trying a Kamak 16GTX. It's a 600cfm turbo, and that's pretty good flow. Even the GTX2867 isn't a massive leap from that at about 700cfm, and I'm probably trading a good 500rpm on the bottom end and some dynamics for that.

Last edited by Back Road Runner; 08-31-2014 at 07:26 PM.
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Old 09-02-2014, 11:24 AM   #29
dark hawk
Scooby Specialist
Member#: 393025
Join Date: Jun 2014
Chapter/Region: MWSOC
Location: Cedar Rapids, IA
1984 Mercedes 300d
Third world taxi


This sounds kick ass
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Old 09-02-2014, 11:34 AM   #30
Scooby Guru
Member#: 81102
Join Date: Feb 2005
Chapter/Region: South East
Location: Clarkesville, GA

Sounds like a vf39 would do more than enough for the op.
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Old 09-03-2014, 01:08 PM   #31
Scooby Specialist
Member#: 10228
Join Date: Sep 2001
2002 Subaru WRX


Might just end up with a SteamSpeed STX67 at this point. Puts me back to big 16g days and then some...

Just got a local quote from them (i live in the same city) now I need to find a good OS tuner now that MPS left the state.
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