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Old 06-12-2013, 03:33 PM   #1
travs05sti
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Default New Turbo? Is Dom 1.5 the best option?

So I have a couple questions. Right now I have a:

2005 sti
Cobb DP
AP OTS map
(currently working on getting my suspension complete, I have Ohlins FPS, RCE blacks. Just need some tophats, endlinks, and sways. So none of that is installed yet)

I got this car a few years ago and I love it. But I've been trying to decide whether to sell my car and get a '11 hatch. Main reason I want a new STI is the styling, the hatch factor, and comfort features. So firstly, I'm curious about any opinions on that.

My main question is I want to make a bit more power, and improve the power characteristics of the car. Here's how I use it and what I want
-I dont track or auto-x, although I may sometime
-Mainly DD/spirited driving
-Fast Spool, good throttle response
-Good top end power
-~350whp+ (the whp number isnt a huge concern)
-Stock location turbo, using TMIC

I want good spooling response AND better top end pull. I know these dont necessarily go hand in hand but I know an aftermarket turbo can improve both over stock. I've done a ton of reading and always thought twin-scroll 20g is the way to go, but I found a really good article that makes me think that the Dom 1.5 twin scroll is the turbo I NEED.

My question is, since this article is a couple years old,
1) Are there better turbos out there now that will satisfy my goals??
2) What makes more sense, 8cm housing or 10cm housing? (using 92 octane)
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Old 06-12-2013, 03:52 PM   #2
Dr. octagon
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Good post and good description
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Old 06-12-2013, 03:55 PM   #3
Dr. octagon
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Good post and good description. not too familiar with dom 1.5.........try looking over in proven power.
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Old 06-12-2013, 03:56 PM   #4
cosseywrx
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Turbo faq thread would be a good start. As well as finding a tuner
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Old 06-12-2013, 04:03 PM   #5
travs05sti
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Might have to go knock on Maxwell Power's door
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Old 06-12-2013, 05:43 PM   #6
tazswing
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and my 11' hatch is for sale with a dom1.5 already on there

little trade off with the 8cm vs 10cm from my research and really it depends on what you will be spending most of your time doing. my sti gets a good amount of daily driving, so having more down low was ideal.

search the proven power bragging but remember the massive dyno to dyno differences.

and as stated, if you end up using a tuner they are one of the best sources of info.
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Old 06-12-2013, 06:46 PM   #7
travs05sti
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Quote:
Originally Posted by tazswing View Post
and my 11' hatch is for sale with a dom1.5 already on there

little trade off with the 8cm vs 10cm from my research and really it depends on what you will be spending most of your time doing. my sti gets a good amount of daily driving, so having more down low was ideal.

search the proven power bragging but remember the massive dyno to dyno differences.

and as stated, if you end up using a tuner they are one of the best sources of info.
Very nice, how much </borat>
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Old 06-13-2013, 01:07 AM   #8
rexwagon02
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I've got a single scroll 1.5 xtr with a Perrin fmic on a built motor. With 900 cc injectors its putting down 405 whp on pump gas with minimal lag. This is in an 07 wagon. The turbo must be nuts on an sti with dual avcs!
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Old 06-13-2013, 10:49 AM   #9
wildt267
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My 06 has a single scroll Dom 1.5 xtr with the 10cm housing and 1000cc injectors. I was able to get 350whp out of it@20psi. My tuner advised me that the 8cm is a better option for daily driving and responds well on these cars. My 10cm is livable but not as responsive as the vf. The twin scroll option may make up that difference but I have no experience to share with you on that. I suggest you pick a reputable shop that specializes in subarus an ask them what results they have gotten with the different options and purchase the turbo from them.
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Old 06-13-2013, 11:06 AM   #10
Kirby10
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I have the Dom 1.5xt-r non twin scroll. I love it and where the stock turbo dropped off this one just carries all the way to redline. This in installed on my 2010 STi . The powerband is great and the power will carry all the way to redline when shifting to the next gear I am right back into boost. I have the 8cm and tuned on 91 and E85. On 18lbs 91octane I am at 300whp. On E85 18lbs 348whp and 21lbs 370whp. This turbo is great.
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Old 06-13-2013, 11:12 AM   #11
travs05sti
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Great feedback guys. It seems that the dom 1.5 is the way to go. People seem to be very happy with it over stock.

I see way more mid range than the 20g on the dyno sheets I've seen, with pretty much the same top end.

But yeah, curious if there was a newer turbo in this category. Seems that it stands alone!
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Old 06-13-2013, 11:15 AM   #12
travs05sti
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Quote:
Originally Posted by rexwagon02 View Post
I've got a single scroll 1.5 xtr with a Perrin fmic on a built motor. With 900 cc injectors its putting down 405 whp on pump gas with minimal lag. This is in an 07 wagon. The turbo must be nuts on an sti with dual avcs!
Wow. Great numbers. You running a 10cm hotside?

I wanted to run TMIC still, shouldn't hold me back should it?
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Old 06-13-2013, 01:23 PM   #13
Kirby10
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I also forgot to add I'm running this turbo with a Perrin FMIC, ID1000cc injectors, Cobb TBE, Grimmspeed up pipe and PnP manifold with hi-flow cross pipe. Running it with a TMIC should be perfectly fine but you will probably get heat soak and that might in turn give you less power.

This turbo is great for a DD car and spools like crazy. I am also able to run low to mid 12s 1/4 mile
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Old 06-13-2013, 11:09 PM   #14
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Quote:
Originally Posted by cosseywrx View Post
Turbo faq thread would be a good start. As well as finding a tuner
Its so far out of date its pathetic.
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Old 06-13-2013, 11:31 PM   #15
cosseywrx
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Still a good start for new subie owners.
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Old 06-14-2013, 12:09 AM   #16
sultan81
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Definitely go 8cm with EWG for the best spool/daily combo.
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Old 06-14-2013, 08:26 AM   #17
travs05sti
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Quote:
Originally Posted by Leafy View Post

Its so far out of date its pathetic.
Yeah it seems pretty out of date. Besides, it doesn't really show me anything that is new and upcoming. I've read some more forums and it seems that the dom 1.5 is the tits.
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Old 06-14-2013, 04:57 PM   #18
tazswing
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If you are every down this way I will take you for a spin.
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Old 06-16-2013, 09:54 AM   #19
lillayzie2000
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Dom 1.5 is plenty. Round these parts (GA) it's king. I went with Dom 2.5 and i've debated over and over on going with 1.5. @ 21lbs it made 417...
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Old 06-16-2013, 09:30 PM   #20
travs05sti
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Quote:
Originally Posted by tazswing View Post
If you are every down this way I will take you for a spin.
Wish I was down that way, I'd take you up on that in a second!

Quote:
Originally Posted by lillayzie2000 View Post
Dom 1.5 is plenty. Round these parts (GA) it's king. I went with Dom 2.5 and i've debated over and over on going with 1.5. @ 21lbs it made 417...
Yeah, it seems amazing. Seems it could easily max your stock internals. Those are amazing numbers.

I'm thinking I just may say "screw the new STi" and build up my '05, fnish the suspension and get some spec B gears.
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