rebuilding stock turbo for high flow?

[ANVIL]

so im starting to do more homework on what turbo setup i want to get and came across the idea of getting a stock 25 turbo rebuilt for high flow. anyone here have any experience or info on this? ive heard about a company GCG that does it and makes the stock turbo capable of 450hp but dont have much details. i emailed them and am waiting for a response. one problem is they are in Aus. are there companies in the US that are reputable and reliable for something like this? how much does something like this cost?

[Cjmartz2k]

Expensive for what they get you and not worth it.

You can get a cheap T3/TO4e for what shipping you turbo out there and getting it back would cost. You can also get a used holset for next to nothing and blow both of those away, or even a new one for under $500.

[ANVIL]

well what im really looking for is something that will get me into the 400-450whp range for a bolt on turbo. or at least one with less customization for fitment.

[Cjmartz2k]

Well a high flow sure as hell ain't going to get you anywhere near that. 450rwhp ain't a small turbo. Holset HX35 would be what I would reccomend. O, and you going to be hard up to find anything in that hp range that's bolt on, let alone for a good price. T3 flanged yes, but rear housing, hell no. Your going to have to get somebody to fab something or weld it yourself.

[Jimefam]

Were is it that everyone finds these hx35's for under $500 new. I check ebay almost daily but the last auction I saw for the 35 ended like two days ago and sold for $800. That is about what i'm seeing and i've contacted a few holset distributors and i'm looking at like $950 new from them? So how about it where do you have them stashed at! I think the secret is out damn it!

[uber95]

Were is it that everyone finds these hx35's for under $500 new. I check ebay almost daily but the last auction I saw for the 35 ended like two days ago and sold for $800. That is about what i'm seeing and i've contacted a few holset distributors and i'm looking at like $950 new from them? So how about it where do you have them stashed at! I think the secret is out damn it!

That's because those qouting those 500 dollar price tags are blowing smoke....

[Cjmartz2k]

I hope that was a joke and your not saying I'm full of ****.

I paid $450 shipped for my HX40 new (and a used one for $250), and got the same deal for two of my friends over here. Same guy had several new and used HX35's for the same kinda prices. It was from a specific ebayer, but I had to do a little research, and ask people what they have other than what's up on ebay. If you had a supply of cheap *** new holsets, would you put them all up on ebay at once and drive down the price? Research.

[craz4240]

I have a custom built rb25 turbo that I will be selling over the winter for 400$.It has a full rebuilt center section and bored efficient supposedly to 24psi but I would run it at 18psi max.Should be good for 350whp-375whp depending on what motor and tune.

I bought the turbo this way and like said above it's a great little turbo but i wouldn't spend the money having it rebored myself.

[ANVIL]

I have a custom built rb25 turbo that I will be selling over the winter for 400$.It has a full rebuilt center section and bored efficient supposedly to 24psi but I would run it at 18psi max.Should be good for 350whp-375whp depending on what motor and tune.

I bought the turbo this way and like said above it's a great little turbo but i wouldn't spend the money having it rebored myself.

dibs!

contact me when you are ready to sell... [email protected] is my email

how hard have you pushed that turbo? is there anyway to verify the rebuild? i might settle for that hp range depending on how i do at the track with it.

[l0nestar]

That's because those quoting those 500 dollar price tags are blowing smoke....

Wait.. a double meaning! I get it!

[l0nestar]

Chris,

Email or AIM me (both in profile)

[craz4240]

dibs!

contact me when you are ready to sell... [email protected] is my email

how hard have you pushed that turbo? is there anyway to verify the rebuild? i might settle for that hp range depending on how i do at the track with it.

Email me your contact info at [email protected] man..

Ummm I have not driven the car much but the turbo has seen 16psi a few times with this setup. I have had the compressor housing off and you can see where the inlet has been borred.Also the wheel is not ceramic (verified against my rb20 wheel) and as well the rb20 compressor housing was WAY too small in the inlet to fit over the wheel and by WAY I mean a good 1/2-3/4 of an inch.Everything externally looks stock and the turbo has very very minimal shaft play (1mm or so).It's a great turbo for the money IMO.....I will hopefully post up some dyno numbers with it at 16psi soon.

[ANVIL]

sweet, ill email you as soon as i get home, i cant check email from work.

do you know who rebuilt it? are you using the stock injectors to 16psi? also, whats the reason you wouldnt go past 18psi if it is efficient to 24psi?

[craz4240]

Just mostly because it is still a small turbo and I would feel more comfortable running 18-20psi instead of the 24psi.

[Jimefam]

No I wasn't saying you were full of **** I was saying that I haven't found any for that price. Also when did you buy yours as I had seen them for that price a couple of years ago but haven't been able to find any now that i'm actually looking to buy. No need to get

[TSL]

Expensive for what they get you and not worth it.

So with your vast experience of GCG high flowed turbos please share with us what exactly you do get.

You can get a cheap T3/TO4e for what shipping you turbo out there and getting it back would cost. You can also get a used holset for next to nothing and blow both of those away, or even a new one for under $500.

I paid $450 shipped for my HX40 new (and a used one for $250), and got the same deal for two of my friends over here. Same guy had several new and used HX35's for the same kinda prices. It was from a specific ebayer...

Yeah, Chinese fakes from ebay are excellent value for money and have a fantastic reputation for quality. I forgot that when buying performance parts that the cheapest stuff is always the best.

Well a high flow sure as hell ain't going to get you anywhere near that. 450rwhp ain't a small turbo. Holset HX35 would be what I would reccomend. O, and you going to be hard up to find anything in that hp range that's bolt on, let alone for a good price. T3 flanged yes, but rear housing, hell no. Your going to have to get somebody to fab something or weld it yourself.

Thanks for sharing your accurate and well researched knowledge of GCG high flow turbos with everybody...Oh no wait, you are just making up a load of sh:t.

The gcg highflow is rated at flywheel power. I'm not sure what they offer these days but gcg used to do a few different versions of the highflow turbos, rated at different power levels. The largest one certainly can make 450hp at the engine. In fact my personal experience of that turbo is that it made 390rwhp on an internally standard R33 RB25det at 20psi with a good tune and appropriate supporting hardware. I would say with aftermarket cams and more boost it could in fact go close to 450whp.

Even without prior experience of these turbos, it is not hard for someone of even moderate intelligence to work out that they are perfectly capable of making the claimed power. The standard turbos have been proven to make 350hp at the engine on less than 14psi so of course the same turbo with a larger compressor wheel and a larger steel exhaust wheel will make a lot more power when you can run a higher boost pressure.

Unlike a diesel truck turbo, the gcg highflow is still responsive giving you more power and torque at lower revs. For the price of a gcg you are essentially getting a brand new custom garrett bb turbo that has been fitted with modified standard compressor and exhaust housings. It is 100% direct bolt on to your standard setup saving time and money on labour and buying/modifying parts to make the thing fit.

The GCG highflow is a good choice if you are after the following...1. Reliable, quality brand name turbo with full warranty/support/service.2. A turbo specifically designed, tested and matched for great results on a specific engine.3. Good response with a respectable power output.4. Easy fitment requiring no extra or custom parts.

The GCG highflow may not be suitable for you if...1. You like generic diesel truck turbos.2. You only care about peak power and not overall response.3. You like having to spend more money on extra parts to fit your turbo.4. You are a smartarse know-it-all that can't afford a decent turbo.

[BoostFab]

so im starting to do more homework on what turbo setup i want to get and came across the idea of getting a stock 25 turbo rebuilt for high flow. anyone here have any experience or info on this? ive heard about a company GCG that does it and makes the stock turbo capable of 450hp but dont have much details. i emailed them and am waiting for a response. one problem is they are in Aus. are there companies in the US that are reputable and reliable for something like this? how much does something like this cost?

why being fancy about it, building the stock turbo to support that turbo end up costing near a larger sized turbo. Just wasting time and money on the stock turbo. just go with a T3/t4 turbo, it's bolt on to the stock manifold, and it's proven for that power range efficiently. some ideas are good, but modifying the stock turbo for that power range is far from it. the stock turbo and high flow doesn't fit in the same sentence. to me high-flow is at leaset 500cfm.

[TSL]

It's not so much being fancy about it. More that different people have different requirements and that you should not tell people that a certain product does not suit them just because it does not suit you.

Sure lot's of turbos bolt to the standard manifold. But what about water and oil lines, exhaust, compressor outlet and inlet piping? Fabrication is not for everybody and factory fitment and look is desired by many people for the "Stealth" look.

As to power output, well that is the most subjective and personal thing of all. I know of many people who feel that 300rwhp is more than enough in a relatively lightweight car. What is the benefit of debating how many cfm's constitutes a high-flow turbo when the term is relative. If a given turbo is improved to flow more than standard, by default it becomes a high-flowed turbo.

A turbo that fits and looks 100% factory standard with proven 400rwhp output is not to be dismissed as a waste.

[BoostFab]

It's not so much being fancy about it. More that different people have different requirements and that you should not tell people that a certain product does not suit them just because it does not suit you.

Sure lot's of turbos bolt to the standard manifold. But what about water and oil lines, exhaust, compressor outlet and inlet piping? Fabrication is not for everybody and factory fitment and look is desired by many people for the "Stealth" look.

As to power output, well that is the most subjective and personal thing of all. I know of many people who feel that 300rwhp is more than enough in a relatively lightweight car. What is the benefit of debating how many cfm's constitutes a high-flow turbo when the term is relative. If a given turbo is improved to flow more than standard, by default it becomes a high-flowed turbo.

A turbo that fits and looks 100% factory standard with proven 400rwhp output is not to be dismissed as a waste.

the point is rebuilding the stock turbo to fulfill his power goal of 450hp, which i'm assuming at the wheel, so that means 530hp at the flywheel , given 15% drivetrain lost. i'm not trying to be unsupportive of the idea, but it's impractical, a rebuilt stock turbo will not get there, period. save your time and trouble, just get an off-the-shelf turbo that is proven! if you want it stealth, don't open your d4mn hood and flashing your goodies!!!!!!!!!

[TSL]

No, the point is providing an appropriate response to the original poster.

Everyone has opinions, the internet is full of it. Providing reliable and accurate information is not so easy to do.

I am simply presenting the known facts about the specific turbo he was asking about based on my own personal experience. All else so far has been false information based on ignorance and speculation.

The original poster specifically mentioned 400-450whp turbo that is direct bolt on...

well what im really looking for is something that will get me into the 400-450whp range for a bolt on turbo. or at least one with less customization for fitment.

The GCG turbo will make 400whp on a standard rb25det, that is a fact. It is a direct bolt on replacement, that is a fact.

It does seem to fit the requirements, why not let him decide if it is right for him.

Why ignore the fact that alternative turbo suggestions will make a few more hp at high rpm at the sacrifice of response, power and torque down low? Why ignore the fact of the additional time and money that is involved in fitting a turbo that is not 100% direct fitment?

If you have evidence that contradicts my experiences of the gcg turbo then feel free to discuss. Baseless opinions will continue to be disregarded as such.

[Cjmartz2k]

O boy, I'm in a big hurry, so I can't fully reply, but I'll look forward to picking all that apart when I get home tomorrow

O, and Jimefam, sorry, I wasn't trying to be *** pissy as that sounded.

*Quicky--TSL, you say the GCG high flow will make 400rwhp on a standard RB25, and that's a "fact". You also ask us for proof of our statements, yet you offer none for your claims. May I see your proof? I do hope you can come up with better than links to GCG's website for manufacturers claims, but even those would be better than nothing.

[TSL]

O boy, I'm in a big hurry, so I can't fully reply, but I'll look forward to picking all that apart when I get home tomorrow

*Quicky--TSL, you say the GCG high flow will make 400rwhp on a standard RB25, and that's a "fact". You also ask us for proof of our statements, yet you offer none for your claims. May I see your proof? I do hope you can come up with better than links to GCG's website for manufacturers claims, but even those would be better than nothing.

Sure i'll get the dyno power graph.

Actually i asked for proof that what i said is incorrect, which you are yet to provide i see. If that is an example of your reading and comprehension skills then i look forward to you "picking all that apart" with great anticipation.

Personally i don't give a fcuk about gcg turbos, to be honest i'm not even sure if they still make the rb25 high-flows any more. Like i said i am simply reporting the facts in direct response to the original poster.

[Cjmartz2k]

From SAU RB25 dyno thread.........

---gcg st.1 450hp high flow turbo . gtr front mount cooler aftermarket manifold, ces racing 3inch split dump, 3inch cat and exhaust. link ecu, malpassi rising rate reg. stock internals and stock cams. 224rwkws at 17.5psi, with more power to come just need new coil before i can run more boost. 224rwkws at 1.2bar shootout mode, dont have scanner to post sheet.

---240 rwkw 96 s2 r33 gtst http://www.host32.com/line/240kw.jpg http://www.host32.com/line/240kwdata.jpg power fc gcg highflow turbo @ 13psi walbro pump fmic 550cc injectors hks pod in ca partition 3" turbo back (standard cat) mobil premium pump fuel

---234 rwkw from my car a couple of days agoGCG highflow CES split dump Fujitsubo 3" cat back with 2 mufflers for quietness panel filter in stock air box 480cc Nismo injectors ROM tune from Powerplay (still to be sorted) About 12-13 psi at peak power (also have boost controller issues)

Still looking, and I can't see dyno graphs, just numbers (govt computer), but those are the first few I came across

[TSL]

From SAU RB25 dyno thread.........

240 rwkw 96 s2 r33 gtst gcg highflow turbo @ 13psi

234 rwkw from my car a couple of days agoGCG highflowAbout 12-13 psi at peak power (also have boost controller issues)

Still looking, and I can't see dyno graphs, just numbers (govt computer), but those are the first few I came across

So you found a couple of examples making around 320whp on 13psi, not hard to see 400whp on 22psi is it?

I appreciate your efforts in supporting my claims.

[Cjmartz2k]

Again, running out the door, so I'll be quick.

Not every turbo makes more power when you go from 14psi to 22 psi, especially small ones. Maybe when I get back I can show you what a compressor map is and explain efficiency

O, and BTW, I saw you browsing the same thread on SUA at the same time. I just posted up the first 3 results I saw. What did you find there cupcake?

[TSL]

It's a shame you're so busy or i'm sure you would totally prove me wrong right?

Please educate me on turbos.

O, and BTW, I saw you browsing the same thread on SUA at the same time. I just posted up the first 3 results I saw. What did you find there cupcake?

I'm quite flattered that you like to take note of my internet movements. While i was over at SAU i found a whole lot of my customers cars i have tuned over the years. How about you? Maybe next time you are on there you should do a search for The SpeedLab and then decide if you want to keep arguing with me over a turbo you clearly have 0 experience with. Ok sweetie pie?

[Cjmartz2k]

O, so you are a tuner and you are arguing about things you are selling. I see now. So, with all that expertise, I'm still waiting for a single result of somebody making the kind of power you are talking about.

BTW, my job is an Air Traffic Controller, and I am busy, but everytime I get out of position to take a short break, on jump on and check up on here.

Ya know, a lot of you Aussie guys are REAL internet smart. Read. Repeat. Read. Repeat. O look, it's been said so many times on the internet, now it must be true!!!

Now seriously, I am walking out the door. Got some beers to kill-- I'll catch you tomorrow sweetie pie

[TSL]

O, so you are a tuner and you are arguing about things you are selling. I see now. So, with all that expertise, I'm still waiting for a single result of somebody making the kind of power you are talking about.

I don't sell anything, i only do specialised mechanical work and tune ecus. I don't even sell those. Like i said before, i don't even know if gcg still do the rb25 high flow so this certainly isn't a sales pitch. Nice try though...

BTW, my job is an Air Traffic Controller, and I am busy, but everytime I get out of position to take a short break, on jump on and check up on here.

I shudder at the thought that someone of such a slender mental capacity for reasoning and comprehension is somehow involved in airline safety.

Ya know, a lot of you Aussie guys are REAL internet smart. Read. Repeat. Read. Repeat. O look, it's been said so many times on the internet, now it must be true!!!

Come on, stop embarrassing yourself. I'm sure if you think really hard you could come up with something better than that childish drivel. I work on dozens of turbo nissans every week. That has been my life for many years. I speak from experience. Let's face it, you are still trying to catch up with what we were doing with these nissans in australia 4 or 5 years ago.

There is absolutely no reason or benefit for me to come on here and make up shi t about some random turbo. You are only getting all pissy because someone corrected you publicly. Take it like a man.

Now seriously, I am walking out the door. Got some beers to kill-- I'll catch you tomorrow sweetie pie

Seeing that you have nothing to offer beyond schoolyard name calling, i think you are done here. Thanks for playing.

Ironically i just looked on the gcg website and i can't see the old rb25 high flow on there anymore. It looks like they may no longer even make it.
Modified by TSL at 11:38 PM 8/16/2008

[Bluefire]

A turbos efficiency range is also a factor in choosing a turbo. A GCG turbo may be able to make 400whp being maxed out, but it will certainly not be within its efficiency range. This in my personal experience with many other turbos results in premature turbo failure. I know a lot of people that have had to replace turbos within 6 months to a year. That being said I would much prefer to use a larger turbo such as a gt30r to safely hit 400-450whp

-Bluefire

[BoostFab]

No, the point is providing an appropriate response to the original poster.

Everyone has opinions, the internet is full of it. Providing reliable and accurate information is not so easy to do.

opinions are like a55-holes, you have yours.

I am simply presenting the known facts about the specific turbo he was asking about based on my own personal experience. All else so far has been false information based on ignorance and speculation.

now your experience invalidate everyone's!? calling someone ignorance doesnt make yourself far from it. you are starting to becoming a big annoynance than helping.

The GCG turbo will make 400whp on a standard rb25det, that is a fact. It is a direct bolt on replacement, that is a fact.

It does seem to fit the requirements, why not let him decide if it is right for him.

to me that is still yet to be proven, i will treat it as "speculation" until i see some evidence. show me the dyno chart of that GCG built stock turbo that put out that power and i'm sold. until then, i see that holds no value. the stock sized turbo chokes on top end, i doubt it making 400whp. even on a high-flow rebuilt. don't forget efficiency factor.

Why ignore the fact that alternative turbo t itsuggestions will make a few more hp at high rpm at the sacrifice of response, power and torque down low?

that again is simply matter of opinion. every know aftermarket upgrade larger than stock turbo is the way to go, for the sake of efficiency and lower boost to get their power goal. i don't give a rat a55 if you push the stock-like turbo to 30psi to make your 400whp, for all i care.

Why ignore the fact of the additional time and money that is involved in fitting a turbo that is not 100% direct fitment?

you have yet to prove the actual price of the GCG's unit make it a better option vs off-the-shelf turbo. again, everyone has their own opinion.