Another garrett question

[HypeR33]

Hi All,

I have another question about the GT30R. INASNT maybe you can answer this as you have one...

I got some specs from Xspeed who sell garretts, about the GT30R, and this is what they gave me.

Water-cooled full ball bearing, non wastegate turbo

Turbo Specs -

Compressor -

Wheel Trim 56

Model - GT40

Wheel Dia. - 2.41"/3.22"

Flow Comp - 65

A/R - 0.70

Turbine -

Wheel Trim - 84

Wheel Dia. - 2.16"/2.36"

A/Rs available: 0.68/0.86/1.00

I thought the GT30R was a wastegate turbo?

[INASNT]

I actually have a GT30 rated at 600hp and use a 45mm turbosmart external gate.

None wastegate turbo means it needs an external gate, which you will need if the 30R flows 650hp.

[HypeR33]

oh ok...i thought it meant that it was an actuator type. Now I understand, thanks mate.

of the choices of wheel diameter, and turbine A/R which would you go for?

The larger compressor wheel diameter? smaller turbine diameter and A/R of 0.86?

Thanks for your help

[RS500]

genereally garrett sell their GT30 turbo range non-wastegated, although some places such as horsepowerinabox have a adapted a internally gated T3 exhaust housing to the GT30 core.

your choice on wheel specs, housings, etc, should depend on the amount of power that you require out of your engine, and how/when you want the power to be produced.

[INASNT]

oh ok...i thought it meant that it was an actuator type. Now I understand, thanks mate.

of the choices of wheel diameter, and turbine A/R which would you go for?

The larger compressor wheel diameter? smaller turbine diameter and A/R of 0.86?

Thanks for your help

as RS500 said, it depends on what you want out of your car.

[R31Nismoid]

Garrett are in the process of bringing integrally gated versions out i think... if they arent already.

But go the external. Much nicer indeed

[HypeR33]

your choice on wheel specs, housings, etc, should depend on the amount of power that you require out of your engine, and how/when you want the power to be produced.

I dont want it to be too laggy, coming on boost in the high 2k - low 3k range, with a rwkw in the 250+ range (with some other mods of course)

[HypeR33]

Garrett are in the process of bringing integrally gated versions out i think... if they arent already.

But go the external. Much nicer indeed  

I definitely want to go external gate I misunderstood what the specs sent me meant. I thought it meant that being non wastegate meant it was actuator. But it's all good

[R31Nismoid]

I dont want it to be too laggy, coming on boost in the high 2k - low 3k range, with a rwkw in the 250+ range (with some other mods of course)  

getting boost... what you mean exactly? you want 16psi on by high 2k?

it wont happen if you wanna make 250rwkw+

[discopotato03]

HyperR33 the specs they gave you are for a GT3040R .

The GT30R (700382-12) uses a 56 trim GT37 compressor in a port shrouded .60 ARR T04E comp cover .

Garrett really should call them GT3037R for their GT30 turbine and GT37 compressor .

Don't let anyone talk you into buying one with a seven bladed T04S compressor as it is not a propper high rpm GT wheel .

[HypeR33]

HyperR33 the specs they gave you are for a GT3040R .  

The GT30R (700382-12) uses a 56 trim GT37 compressor in a port shrouded .60 ARR T04E comp cover .  

Garrett really should call them GT3037R for their GT30 turbine and GT37 compressor .  

Don't let anyone talk you into buying one with a seven bladed T04S compressor as it is not a propper high rpm GT wheel .

Thanks disco...so is the GT3040R that they gave me the specs for A T04S compressor? I want to make sure I make the right choice

[HypeR33]

getting boost... what you mean exactly?  you want 16psi on by high 2k?

it wont happen if you wanna make 250rwkw+

I just mean starting to get positive boost pressure in the high 2k - low 3k range. I know it probably wouldn't hit the 16-18psi I am after until way higher in the rev range. I just dont want it to not boost at all until 4k - 5k.

[discopotato03]

HypeR33 count the number of blades looking into the compressor housing . If it has 6 full height and six half height it will be a BCI 18C series GT wheel . If it has 7 full and 7 half height it is a T04S wheel .

The rule of thumb with compressors is the lower the number of blades and the thinner the blades , the more efficient an air pump it is .

The BCI 18C range of compressors are designed to be a high speed wheel ie the angle of attack of the blades is shallower that the T04S . They (BCI 18C) have less innitial bite into the air so that all available energy (shaft power) from the turbine is available to spin it up and generate airflow (boost) . They have an extended rev range compared to earlier designs , and this is why they pump as much or more air than earlier designs while being smaller and lighter . Being mechanically strong (more able to withstand the centrifugal forces of high rpm) allows the compressor to be compact , and light weight (less mass to accelerate) so helps reduce the innertial lag component of getting to boost rpms .

When Garrett developed the GT or Garrett Technology series , most of the effort innitially went into the turbines because this part had the greatest potential for improvement . Because bush bearings (and plate type thrust bearings) limit the rpm of the shaft , high speed wheels were not designed in the past because the bearing system could not reliably survive higher rpm's .

The GT turbine and matching turbine housing is a set and should not be fiddled with apart from ARR changes . These turbines are much much lighter than the dinosaurs they replaced . They have a more paddle bladed appearance or greater tip height . The nozzle or channel in the turbine housing is wider and allows greater mass flow across the blade inducer tips than earlier designs . GT turbines and matching housings have quite high specific flow ratings for their physical size , they can easily out flow T4 turbines and housings while being lighter and more compact . Like the compressors they are also much better able to stand higher cetrifugal forces .

So Garrett produced these wonderful turbines and hung old school compressors on them while compressor development went on . They had oodles of the old types and the market bought them like hot cakes . There's and old marketing saying , if it sells why change it . They still sell and people still buy them , generally the sharks sell them a little cheaper and still call them a GT30R - but its not the real one . Ball Bearings yes , modern efficient compressor no . Dont forget an inefficient compressor drags turbine efficiency down with it . Add some bastardised modified non GT type turbine housing and you've built a real dog .

For your own sake do it once do it right - even if the right one costs a little more . Trust me its cheaper in the long run .

[32vspecII]

any recomendations on where to get these "good" gt30s ?

[R31Nismoid]

just ask for a 6 bladed (GT series comp wheel) GT30

i got one Its not hard.

[discopotato03]

Garret sells the turbo minus the turbine housing ie centre housing rotating assembly (CHRA) with compressor cover and backplate . Its part no is 700382-12 .

There are three available non gated turbine housings ie .63 , .82 and 1.06 AR ratios . Housing part nos are 740902-2 (.82) and 740902-1 (1.06) , not sure about the .63 version .

Alternatively HKS do a .68 and a .87 AR integral gate housing also in T3 flange . GCG can get them but not cheap at $800 ea . I believe these two are aimed at RB20's and RB25's with HKS's GT3037 which uses the same identical CHRA as the GT30R . In fact the ONLY difference between the GT30R / HKS GT3037S is a slightly different version of the port shrouded compressor cover (bell mouthed) .

I was recently acused of pushing GCG's name so if anyone asks no I don't work for them or anyone remotely involved in the automotive industry .

Hope this helps , cheers A .

[MonstaS4]

The GT3040R is available with the 6 bladed GT wheel from MTQ engine systems. Part No. is SB8006 for a 1.06 AR exhaust or SB8006A for a 0.82 AR exhaust. These are straight out of the Garrett "Ballistic Concepts" catalog.

[R31Nismoid]

In fact the ONLY difference between the GT30R / HKS GT3037S is a slightly different version of the  port shrouded compressor cover (bell mouthed)

yeah, dead on. There is a combo out there in the GT30 series that is basically identical to the 3037, same response and everything. But its rated slightly lower than the 600hp version from memory, but yeah... it comes with more response

[HypeR33]

HypeR33 count the number of blades looking into the compressor housing . If it has 6 full height and six half height it will be a BCI 18C series GT wheel . If it has 7 full and 7 half height it is a T04S wheel .  

The rule of thumb with compressors is the lower the number of blades and the thinner the blades , the more efficient an air pump it is .  

The BCI 18C range of compressors are designed to be a high speed wheel ie the angle of attack of the blades is shallower that the T04S . They (BCI 18C) have less innitial bite into the air so that all available energy (shaft power) from the turbine is available to spin it up and generate airflow (boost) . They have an extended rev range compared to earlier designs , and this is why they pump as much or more air than earlier designs while being smaller and lighter . Being mechanically strong (more able to withstand the centrifugal forces of high rpm) allows the compressor to be compact , and light weight (less mass to accelerate) so helps reduce the innertial lag component of getting to boost rpms .  

When Garrett developed the GT or Garrett Technology series , most of the effort innitially went into the turbines because this part had the greatest potential for improvement . Because bush bearings (and plate type thrust bearings) limit the rpm of the shaft , high speed wheels were not designed in the past because the bearing system could not reliably survive higher rpm's .  

The GT turbine and matching turbine housing is a set and should not be fiddled with apart from ARR changes . These turbines are much much lighter than the dinosaurs they replaced . They have a more paddle bladed appearance or greater tip height . The nozzle or channel in the turbine housing is wider and allows greater mass flow across the blade inducer tips than earlier designs . GT turbines and matching housings have quite high specific flow ratings for their physical size , they can easily out flow T4 turbines and housings while being lighter and more compact . Like the compressors they are also much better able to stand higher cetrifugal forces .

So Garrett produced these wonderful turbines and hung old school compressors on them while compressor development went on . They had oodles of the old types and the market bought them like hot cakes . There's and old marketing saying , if it sells why change it . They still sell and people still buy them , generally the sharks sell them a little cheaper and still call them a GT30R - but its not the real one . Ball Bearings yes , modern efficient compressor no . Dont forget an inefficient compressor drags turbine efficiency down with it  . Add some bastardised modified non GT type turbine housing and you've built a real dog .

For your own sake do it once do it right - even if the right one costs a little more . Trust me its cheaper in the long run .

Hey disco, thanks for all the info man. Much appreciated I definitely want to make the first choice the right one

[32vspecII]

Ok I think I got it , I would want one of these turbos right . This is from the ray hall site . sorry about the formatting

Complete Turbochargers Compressor Stage Turbine Stage

Model Turbocharger part No CHRA Part No Hsg. A/R Wheel Trim Model Wheel Dia Horse Power Comp Flow lbs Hsg. A/R Wheel Trim Wheel Dia

GT30 SB8006A 700177-0014 0.7 64 GT40 2.41/3.22 550 65 0.82 84 2.16/2.36

GT30 SB8006 700177-0014 0.7 64 GT40 2.41/3.22 600 65 1.06 84 2.16/2.36