My Custom Gt28 Turbo

[jmac]

Hey guys,

Got a custom "prototype" turbo upgrade from MTQ for a cheap(er) price. Bolted on to the factory dump pipe.

Rang them and got some specs, just wondering what you guys think of this combination of wheel sizes, etc - will this spool quickly once tuned, how much power will it make, any comments etc.

Current mods: pod, 3" cat-back, Turbotech valve running ~10-11 PSI.

Planned mods are dump/front pipe, cat, PFC, FMIC, fuel pump+regulator, 480cc injectors, Z32 AFM. Planning for 230 rwkws keeping boost 14-16 PSI.

Eventually...

This is what I was told:

Ball bearing Garrett core.

"The biggest T28 we have"

Rated at "500 hp"

Compressor wheel:

Inducer 52mm

Trim 48

Turbine wheel:

Exducer 47mm

Trim 76

Serial numbers on new turbo:

IE 0105J

446179 5018

See attached "before and after" photos... (before = stock R34 GT-T turbo)

[Dale FZ1]

By the look of things, this is a high flow job, fitting a new core to existing housings?

[boj01]

Might not spool up as quick because it has a steel rear wheel rather than the nylon one?

[discopotato03]

446179-0018 = 76mm 48T T04S compressor driven by 54mm 76T GT28 (NS111) turbine . Large diametre small trim dinosaur comp driven by small dia med trim GT turbine - sounds laggy to me . Along the lines of HKS's old superceeded GT2540R but worse - lower aero tech comp + non native turbine housing .

Let us know how it goes .

Cheers A .

[jmac]

Hmmmm... interesting how that doesn't match up to what they told me.

This wasn't just a normal high-flow job I was told... they asked to have a few days extra as this was some "prototype" they were doing. They actually quoted me on a standard high-flow, then also quoted on an off-the-shelf Garrett unit, but said this was a bolt-on option they were working on for R34s.

Now I'm wondering what the hell I actually got...

The plot thickens....

[paulr33]

the stocker hiflow uses garrett ball bearing chra kit and mounts to standard oil and water lines and dump. does this custom t28 have the same features? strange that they've given you a pilot turbo. cant hurt to try i guess, what u gonna do if its crap?

[jmac]

nah this needed custom oil and water lines... bolted on to factory dump pipe no worries though.

don't really know how it's going to run until i ditch factory computer and tune a PFC properly i guess.

if it sux i guess i might take it back and throw it at them... i dunno... major weirdness.

[RACESPEC]

so they have basically put the GT2540R core into yours

Thanks

Tarek

RACESPEC

[choyda]

Well I'm going R34 hiflow this week (turbo comes out in 2 hours). I'll take pics and ask for exact sizes (I'm getting slightly larger internals) to compare.

[discopotato03]

Basically thats the one . I wish people would stop selling that GT25/T04S piece of crap , there's nothing 40 or GT40 about the compressor . HKS's version was slightly better (not much) because it used a small trim (46) T04"E" 6 bladed 76mm wheel but they wisely flicked it for a larger trim smaller O/D ie 52 trim 71mm BCI-18 (GT series) wheel . Its called a GT-RS or GT2871R in Garrett speak and can be had without the HKS ID or price tags .

For anyone interested in the GT2871R series the turbo and cartridge (CHRA) numbers are as follows .

1) GT2871R 48T comp 49.19mm ind : unit no 743347-1 , CHRA no 446179-31 .

2) GT2871R 52T comp 51.20mm ind : unit no 472560-15 , CHRA no 446179-67 .

3) GT2871R 56T comp 53.13mm ind : unit no 743347-2 , CHRA no 446179-32 .

The Garrett Site tells you the 2540R is not a performance turbo , more a display case racer .

Cheers A .

Edited November 4, 2005 by discopotato03

[jmac]

The way I interpret the CHRA no (446179-0018) as matching the GT2876R... so they've put that core into R34 housings I guess?

Garrett site:

* Ball bearing

* Oil & Water-cooled bearing system

* Best suited for unique applications such as asymmetric turbo installations

* Not recommended for general performance applications

* T25 turbine inlet flange

* Turbine housing option available

* Actuator not included

So I'm not sure what the MTQ guys were thinking....

[RACESPEC]

Basically thats the one . I wish people would stop selling that GT25/T04S piece of crap , there's nothing 40 or GT40 about the compressor . HKS's version was slightly better (not much) because it used a small trim (46) T04"E" 6 bladed 76mm wheel but they wisely flicked it for a larger trim smaller O/D ie 52 trim 71mm BCI-18 (GT series) wheel . Its called a GT-RS or GT2871R in Garrett speak and can be had without the HKS ID or price tags .

For anyone interested in the GT2871R series the turbo and cartridge (CHRA) numbers are as follows .

1) GT2871R 48T comp 49.19mm ind : unit no 743347-1  , CHRA no 446179-31 .

2) GT2871R 52T comp 51.20mm ind : unit no 472560-15 , CHRA no 446179-67 .

3) GT2871R 56T comp 53.13mm ind : unit no 743347-2  , CHRA no 446179-32 .

The Garrett Site tells you the 2540R is not a performance turbo , more a display case racer .

Cheers  A .

<{POST_SNAPBACK}>

A

Thats the one we cant get our hands on

otherwise you can use the GT2535R

which is available in 48 and 56 trim for both housing sizes

SB8031 and 8032

Thanks

Tarek

RACESPEC

[discopotato03]

The 48T 446179-31 will be the most responsive anyway . It is the next step up from the GT28RS (2860RS) 446179-66 in terms of airflow and response . I'll take average power over a thimble full at the top end any day .

[Dale FZ1]

Well I'm going R34 hiflow this week (turbo comes out in 2 hours).  I'll take pics and ask for exact sizes (I'm getting slightly larger internals) to compare.

<{POST_SNAPBACK}>

What upgrade did you use Choyda?

ID numbers if possible please.

[INASNT]

That little turbo will not be rated to 500hp.

Have the people that put it together made any guarantees to how it will run?

[jmac]

No specific guarantees, no. Like I said it's a prototype unit and they're actually keen to hear back from me once I get it tuned and running properly (slowly getting all the bits together to do so now). I think MTQ are trying to do more work like this 'cos they've probably been missing out on business.

I'm not expecting 500hp, but hopefully it will make my goal of 260-290 rwkw (that's with PFC, 3" exhaust, FMIC, pump, injectors etc). I'm very curious to see how it goes given everyone seems to think it'll be pretty laggy.

[R31Nismoid]

290 at the treads with a t28 hybrid?

Remember, 500hp turbo, thats not the rating @ the rear wheels dude.

you'll be pushing the sh|t up the hill around 260.

let alone another 30rwkw

[paulr33]

also what good is 260rwkw if its lag city. food for thought. average power makes a car fast not a max power reading at 7000rpm

[jmac]

Actually I thought torque did.

Anyway all this is academic until I get it tuned. I didn't come on here to boast about dyno figures that don't exist, just wanted some opinions about this particular turbo because I'm not an expert on this. I got the "290 rwkw" figure from a fellow SAU member who knew of a guy with a similar spec to what I'm planning and his car made that number.

I also have enough understanding to realise that a turbo's hp rating doesn't mean it's going to magically "make" that number. :lol:

I'd much rather a low-lag, nice beefy torque curve. So we'll just see how it goes. The turbo's already bolted onto the car and I don't think the lag has increased that much compared with the factory unit. MTQ are meant to be an experienced lot who know what they're doing so we'll just see.

Cheers guys...

Edited November 12, 2005 by jmac

[INASNT]

Actually I thought torque did.

Anyway all this is academic until I get it tuned.  I didn't come on here to boast about dyno figures that don't exist, just wanted some opinions about this particular turbo because I'm not an expert on this.  I got the "290 rwkw" figure from a fellow SAU member who knew of a guy with a similar spec to what I'm planning and his car made that number.

I also have enough understanding to realise that a turbo's hp rating doesn't mean it's going to magically "make" that number.  :lol:

I'd much rather a low-lag, nice beefy torque curve.  So we'll just see how it goes.  The turbo's already bolted onto the car and I don't think the lag has increased that much compared with the factory unit.  MTQ are meant to be an experienced lot who know what they're doing so we'll just see.

Cheers guys...

<{POST_SNAPBACK}>

Unless u have alot of engine work done that 290rwkw figure is a dream