Is a GT1749V a VNT15 turbo ?

HDIesel

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Joined
Jan 7, 2001
Location
Finland
TDI
Smurf_bus HDI
different name but the same turbo!!!

Are you still getting smoke with that huge IC?
 
S

SkyPup

Guest
That is the larger VNT15 with 49mm compressor wheel instead of the 46mm one.

ere are the Model Designation and Wheel Diameters for the older T-series and the new GTVNT Series Garrett Turbochargers:

(mm) (mm)
Model Compress Wheel Dia Turbine Wheel Dia
T2 48.0 47.0
T25 51.4 53.0
HFT25 54.4 53.0
T3 60.0 59.0
GTVNT15-46 45.7 41.2
GTVNT15-49 49.0 44.2
GTVNT25-52 52.2 47.0
GTVNT 25-56 55.8 50.3

The GTVNT15-46 replaces the T2 Garrett Turbo, the GTVNT15-49 replaces the T25 series, the GTVNT25-52 replaces the HFT25 model, and the GTVNT25-56 replaces the T3 model.

The inlet diameter of the newly designed impellers of the GTVNT series is slightly larger (0.56mm) than that of the corresponding T-series it replaces. When compared at a pressure ratio of 1.8:1, the flowrate efficiency at 65% on the surge side for the GTVNT is similar to that of the previous T3 turbo, while producing a much higher flowrate at 65% efficiency on the choke side! A significant improvement of 19% in useable flow rate is achieved. With a pressure ratio of 1.8:1 and a flowrate of 9kg/min, an increase of 7.5% in efficiency is noted.
During the initial phase of the development of the new GTVNT15/25 series Garrett turbochargers, a number of objectives for improving the current production turbines were sought. These objectives were: to improve the turbine flow characteristics, minimize size and weight, minimize inertia, improve transient response times, and to improve the aerodynamics of the turbine housing.
The new GTVNT turbine housing features improvements made through the modification of the waste gate housing as well as that of the tongue location. The wastegate flow section was improved by providing a straighter gas path for the bypass flow to exit. The tongue was positioned closer to the wheel inlet to minimize wall frictional losses in the region of high trangential flow and high gas velocities beyond Mach 1.
The new turbine wheel of the GTVNT25-52 series features a smaller blade count as compared with the earlier T2 model (9 vs 11) and also features longer blades and a higher trim than the T2 model (67 vs 57), although the turbine tip diameter is the same as that of the T2 (47mm). Turbine corrected flow plotted against turbine housing size for a constant turbine pressure (P1T/P2 = 1.8) for the new GTVNT25-52 shows turbine flows within approximately 4% of the larger T2 turbine and 30% higher than the equilivant sized T2 turbine. The new compressor wheel design shows the compressor wheel diameter vs airflow for the entire GTVNT family as compared to the T2-T3 series, has successfully achieved wheel size reduction for equal air flow rate.

Comparison of Features of older T25 and new GTVNT15-49 Turbochargers of Equal Compressor Flow Capacity:

COMPRESSOR WHEEL T25 GTVNT15-49 %Reduction
Diameter (mm) 51.4 49.0 4.7
Weight (g) 33.1 26.3 20.5
Inertia (kg-m2) .0000057 .0000043 24.6

TURBINE WHEEL
Diameter(mm) 53.0 44.2 16.6
Weight(g) 148.4 112.5 24.2
Inertia (kg-m2) .0000148 .0000103 30.4

TOTAL TURBO WT(kg) 5.43 4.55 16.2
SHAFT DIAMETER(mm) 9.2 7.9 14.1
TOTAL TURBO
ROTATING INERTIA(kg-m2) .0000208 .0000149 28.4

Corrected TURBINE FLOW (kg/min) at 1.7 Pressure Ratio and .47 Housing Size for:
Garrett GTVNT15-46 = 3.85 kg/min
Garrett GTVNT15-49 = 4.30 kg/min

Corrected COMPRESSOR FLOW 9kg/min) at 1.8 Pressure Ratio and 65% efficiency in 55 Trim for:
Garrett GTVNT15-46 = 7.8 kg/min
Garrett GTVNT15-49 = 9.8 kg/min

This data show that the new GTVNT15-46 turbocharger flow the same as the older and larger T2 series turbo, while the new GTVNT15-49 turbo flows slightly less than the older design T25 turbo. The reduction in size of the turbine housing, turbine wheels, and compressor wheels in the new GTVNT series turbochargers while maintaining comparable flow characteristics and improving the Performance Maps efficiency on the choke side of the Map has resulted in significant improvement in useable flow range over the previous T2-T3-T25 series turbos.

As the data from Garrett Motorsports Turbocharger Division of Allied Signal shows, there are two models of GTVNT15 turbos, one (GTNVT15-46) has a 41.2mm turbine blade and a 45.7 compressor wheel, while the other (GTVNT15-49) has a 44.2mm turbine blade and a 49.0mm compressor wheel. the larger turbine wheel and compressor wheel of the GTVNT15-49 compared to the GTVNT15 gives an 11% increase in turbine gas flow as well as a 13% increase in compressor flow.

[ September 12, 2002, 05:11: Message edited by: SkyPup ]
 

PTC

Veteran Member
Joined
Oct 4, 2000
Location
Zagreb, Croatia
TDI
HMaracic
Originally posted by Anders:
I have a euro tdi with 110 and on my turbo it saids GT1749V. I thought that the turbo on my car was the VNT15 ??

Please help....
<font size="2" face="Verdana, Helvetica, sans-serif">Could you please check and tell us is your engine AFN, AHF, or ASV?

Thanks!
 
M

mickey

Guest
Yes, the 49V is a "VNT-15" with a larger compressor wheel than the 46V.

A VNT-17 is the next larger "family" of turbos.

I have a VNT-25 I bought on Ebay. It happens to be the smallest of the VNT-25 family. There are five or six larger ones, I believe. As I understand it, the "family" uses the same basic housings and center section. Just slightly different wheel sizes and trims.

-mickey
 
S

SkyPup

Guest
Here is a *****in' mo-fo VNT17 on a TDI-R PD race engine.


Me Want.



[ September 13, 2002, 04:47: Message edited by: SkyPup ]
 

Anders

Active member
Joined
Oct 29, 2001
Location
Helsingør, Denmark
No smoke right now. I have blown the turbo and I don't know which one I want. I will proberly get a VNT17 and see how that will work on my car.

I will also have the chip changed sp that I dont have 434 nm at 2000 rpm's. The driveability is not good right now. I want max nm at around 2500 rpm's.
 

CADDY

Veteran Member
Joined
Feb 20, 2002
Location
france
nice turbo!!
i have an afn, what is the vnt on?
i think i have yhe small vnt-15.......snif.
 

Anders

Active member
Joined
Oct 29, 2001
Location
Helsingør, Denmark
Is your engine the 110 hp or the 90 hp ? If you have the 110 hp as I have you have the VNT15 with 49V. I will within two weeks have a new and bigger turbo (VNT17) on my car and when I will tell you all how it is running. I my also having my cam changed so that is also something that I look forward to test. More to come...
 

nApkIn

Veteran Member
Joined
Nov 19, 2001
Location
Germany
where can we get those "vnt-17" turbos?

anders! i got an vnt-15 with a larger wheel like the number on the turbo says. but it is from a 130hp pumpe duse engine.. so what is the steady boost of the 130 hp engine?

and where the hell is a vnt-17 put in?????

cuall
 

RedRotors

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Joined
Dec 3, 2001
Location
On the road.. Qc.
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Golk 2k1 TDI / Dodge RAM 94', 2500, 4x4, Cummins
Originally posted by mickey:
Yes, the 49V is a "VNT-15" with a larger compressor wheel than the 46V.

A VNT-17 is the next larger "family" of turbos.

I have a VNT-25 I bought on Ebay. It happens to be the smallest of the VNT-25 family. There are five or six larger ones, I believe. As I understand it, the "family" uses the same basic housings and center section. Just slightly different wheel sizes and trims.

-mickey
<font size="2" face="Verdana, Helvetica, sans-serif">Can you drop me a line? I'm curious if it's the same that i want to bid on it...

Marc
 

CADDY

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Joined
Feb 20, 2002
Location
france
ANOTHER QUESTION...
nice intake manifold ,were does it come from?
is it a special one for race?
 

AtomicSushi

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Joined
Sep 18, 2001
Location
Rancho Cordova, CA
TDI
2002 Black Golf GL
Bringing up this old thread.....
I was wondering if the GT1749V with manifold as meant for the PD115 TDI is a bolt on to an ALH TDI?
Same housing, just bigger wheels.
Should said turbo be bolted on (and a larger intercooler attached) would this provide any improvement over the stock GT1746 when fueling is via PP520s and an 11MM pump.
 

RAVEN

Well-known member
Joined
Apr 29, 2003
Guys has anyone fitted a VNT turbo as an upgrade from the non vnt type?? and if so whats the outcome!
Thanks
 

ian-b

Member
Joined
Sep 13, 2010
Location
marquette michigan
TDI
2001 Jetta TDI 5spd
My vnt-15 is bad and I have a gt1749v to replace it with. I know it bolts up and all that. Will I be ok running it without changing anything else? Is the larger wheel a big enough difference to make me need to tune? The exhaust housing on my vnt-15 is in better shape. Can I put the gt1749v cartridge into my old manifold of did they change that with the 1749v too? Figured I would add to this thread because it's titled properly for these kinds of questions.
 

ian-b

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Sep 13, 2010
Location
marquette michigan
TDI
2001 Jetta TDI 5spd
I know it would be optimal. I'm new to diesels not tuning and turbos. I've build and tuned my own megasquirt for my subaru before. I just want to make sure I can get the car up and running and drive it a bit without issue. And I need to know if I can put my 1749v cold side and cartridge into the original vnt15 manifold. Are they different? The 1749 one I have has some messed up bolt holes I'd rather not have to monkey with. Anyone know?
 

cog

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Feb 6, 2008
Location
MIDDLESBROUGH... U.K
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98 GT.TDI 11O
No smoke right now. I have blown the turbo and I don't know which one I want. I will proberly get a VNT17 and see how that will work on my car.

I will also have the chip changed sp that I dont have 434 nm at 2000 rpm's. The driveability is not good right now. I want max nm at around 2500 rpm's.
the 110 works very well on its stock turbo and pp764 injectors and tune. but i can tell you the vnt 17 works very well in deed on the 110 if you give it enough fuel .
 

jackfolstam

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Joined
Oct 14, 2016
Location
CA
TDI
MkI Rabbit ALH swap
The exhaust housing on my vnt-15 is in better shape. Can I put the gt1749v cartridge into my old manifold of did they change that with the 1749v too? Figured I would add to this thread because it's titled properly for these kinds of questions.
seven more years!
 
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