The Garrett Gt30r Thread - Lots Of Info And Q's

[The Mafia]

ok - Here are some updated specs on the turbo that I am looking at:

The GT3076 with these specs - (700177-0023 or -5023)

The Compressor wheel specifications should be : 71mm 56 trim (or should it be the 52 trim?)

The Compressor Cover : .6xx a\r? (need a 4 inch bell mouth) (maybe the .65 cover Disco wants to test?)

The Turbine Specs should be: (I have no idea)

The Exhaust housing will be a Garret IW .82 GT30

Can anyone fill in the blanks?

I'm going to get this right this time!

Edited November 15, 2006 by The Mafia

[Slide]

ok - Here are some updated specs on the turbo that I am looking at:

The GT3076 with these specs - (700177-0023 or -5023)

The Compressor wheel specifications should be : 71mm 56 trim (or should it be the 52 trim?)

71mm 56 trim

The Compressor Cover : .6xx a\r? (need a 4 inch bell mouth) (maybe the .65 cover Disco wants to test?)

.60 A/R

The Turbine Specs should be: (I have no idea)

84 trim 60mm GT30

The Exhaust housing will be a Garret IW .82 GT30

Can anyone fill in the blanks?

I'm going to get this right this time!

[The Mafia]

Thanks Slide, that was very much appreciated.

Here are some even more updated specs on the turbo that I am looking at:

The GT3076 with these specs - (700177-0023 or -5023)

The Compressor wheel specifications should be : 71mm 56 trim

The Compressor Cover : .60 a\r (need a 4 inch bell mouth, Intake is already 4 inch)

The Turbine Specs should be: 84 trim 60mm GT30

The Exhaust housing will be a Garret IW .82 GT30

ok, so there is a turbo build.

I'm HOPING, this will give me a lot less trouble than the monster I have on there now.

I went for a drive last night, and it went pretty damn good to tell you the truth. The car is going on the Rollers in about 30 mins, so I'll post a dyno sheet on what the T04S wheel and .63 housing can do.

Seriously, last night I was surprised at the power I was making.

DIsco, can you have a look at the specs above, and confirm that they are good enough to hand to garrett for the production of my turbo?

Are there any ithet things I need to add? Do you think I should wait for you to test this ".65" housing you keep mentioning?

Also, what kindof boost will this setup handle. I'll probably end up going to forgies at some stage later down the track.

Edited November 15, 2006 by The Mafia

[Dale FZ1]

Thanks Slide, that was very much appreciated.

Here are some even more updated specs on the turbo that I am looking at:

The GT3076 with these specs - (700177-0023 or -5023)

The Compressor wheel specifications should be : 71mm 56 trim

The Compressor Cover : .60 a\r (need a 4 inch bell mouth, Intake is already 4 inch)

The Turbine Specs should be: 84 trim 60mm GT30

The Exhaust housing will be a Garret IW .82 GT30

ok, so there is a turbo build.

There is a 0.50A/R comp cover that has a 4 inch inlet / 2 inch outlet as per the turbobygarrett product sheet.

That combination should just crack the 270rwkW power target but it will take a fair whack of boost on a stock engine. Overall it will probably give a good result.

Late edit: the -0023 comb is a 3071 ie 71mm compressor. Yes, I am talking about that unit using a 0.50 A/R comp cover with 4 inch inlet, and yes, I think it should hit that power target (only just, and running pretty hard to do it). But it should be streetable with good power through the range.

Slide, this is your area of expertise. Any ideas? Clearly there is opportunity for business here.

cheers.

Edited November 16, 2006 by Dale FZ1

[discopotato03]

Dale FZ1 that Turbomaster cattledog has a misprint , 76.2mm by 57mm is very close to 56 trim . Had the number been 76.2mm by 55mm it would be 52 trim . If you have another look at the GT3776 it should show the compressor dimensions and trim number . If not do a search on their GT3571 because I think there was also a GT37 compressor option of 52 trim . I know the GT3576 is 52 trim but not easy to find data on .

You should probably look at the GT3076R's map and compare that with the 54AR GT3776 , the housing AR is part of the reason for this . Fingers crossed the .65AR housing would make the 76.2mm 52 trim GT37's map look a bit more like the GT4082's map , wider or fatter across the lower pressure ratio region . I have a pic of that .65AR cover and notice it uses a different clamping method than the TO4B/E/S type housings .

Mafia that turbo you are looking into is a GT3071R not a GT3076R , the only available (off the shelf) compressor trim option is 56 . There are three optional compressor housing kits (housing/adapter ring/seal/circlip) and I'm sure one is port shrouded so must be 4" (100mm) snout . Have to dig through my lists to find its part no and AR ratio number .

Busky2K , posted last night but lost to WiFi . Yes the 48/52/56 trim TO4S wheels are around 76mm , actually my Garrett 52 and 56T maps say 76.1mm .

The HKS GT2540 was a little unusual in that it used a 76.something mm TO4E compressor in 46 trim . Not positive but I expect the 76.2mm BCI-18C (GT37) wheels were not available at that time and HKS could not stoop low enough to use the 48 trim TO4S compressor like Garrett did in their GT2540R . Neither are very good the HKS version just a bit less useless , their GT2871R 52T (GT-RS) not perfect but much better than the other two .

What Arnie said , cheers A .

[discopotato03]

Compressor housing kits for Garrett GT3071R using Centre Housing Rotaring Assembly (CHRA or cartridge) number 700177-5023 . Includes Housing , adapter ring , O rings , clamps and bolts .

1) 756021-1 2" Outlet 2.75" Inlet . 0.50AR

2) 756021-2 2" Outlet 4.00" Inlet . 0.50AR

3) 756021-3 2" Outlet 4.00" Inlet . 0.60AR Port Shrouded .

The good news is that the 4" inlet port shrouded version is 0.60AR ratio so you have a bit more leeway with exhaust housing AR sizes and less likely to suffer compressor surge . HKS uses port shrouded compressor housings on their RB specific GT2835 series which uses the same family of compressor and in fact the GT2835 Pro S almost certainly uses the same comp wheel . Again I'll have to have a look at theirs to see if the housing AR ratio is 0.50 or 0.60 .

And thinking about it that comp cover would be the one to reprofile if anyone wanted to build up a GT3076R using the smaller 52 trim 76.2mm GT compressor .

Cheers A .

[discopotato03]

HKS say thay use a 0.50 ratio port shrouded cover though the one on their 2835 Pro S is a special so no AR marking shown . If anyone has one of these turbos kicking around could they look inside the compressor housing outlet and tell us if is has 50 or 60 marked just inside .

Cheers A .

[The Mafia]

Mafia that turbo you are looking into is a GT3071R not a GT3076R , the only available (off the shelf) compressor trim option is 56 . There are three optional compressor housing kits (housing/adapter ring/seal/circlip) and I'm sure one is port shrouded so must be 4" (100mm) snout . Have to dig through my lists to find its part no and AR ratio number .

Disco

So those specs that I have posted are for the 3071? Well, what are the 3076? DO you think you can update my post with what you think I should be choosing?

I'll attached a spreadsheet I have recieved this morning. The Guy I spoke to - Bob stafford. He seems to know his stuff when it comes to turbo charactisitics.

He is saying that the compressor in my turbo is larger than the 3076 wheel we are looking at, but the turbine wheel is definately larger than the one I currently have.

As for the 3076 that we are trying to "build" in this thread... I have never been more confused... Disco, you need to list the parts that you recommend for me ie Wheel size, trim, turbine size, trim, housing sizes.

Thanks

[edit] master bom.xls attached as master bom.txt - rename to .xls (just right slock, save as)

Master_BOM.txt

Edited November 16, 2006 by The Mafia

[discopotato03]

Hi Mafia , this is going round in circles because I'm not sure what you don't understand .

Real GT3071R spec (no complete turbocharger number because its sold as a cartridge and housing kits)

Turbine : GT30 84 trim (60.1mm inducer diametre by 55mm exducer) .

Compressor : 71.1mm 56 trim .

Cartridge number : 700177-5023 .

Real GT3076R spec (complete turbocharger number is 700382-12)

Turbine : GT30 84 trim (60.1mm inducer diametre by 55mm exducer) .

Compressor : 76.2mm 56 trim .

Cartridge number : 700177-5007

Some Garrett wheel families :

Turbines :

GT28 53.85mm .

GT30 60mm normal version .

GT30 56.6mm - cropped version like you have .

GT35 68mm .

GT37 72.5mm .

GT40 77mm

GT42 82mm

Compressors :

GT30 60.1mm .

GT35 71.1mm . GT3071R uses these .

GT37 76.2mm . GT3076R and HKS GT3037 use these

TO4S 76.1mm . One of which you have

GT40 82mm .

GT40 88mm .

Garrett turbo names are based on the turbine series numbers ie GT30 and nowdays the compressor diametre in mm . So this is why a GT3071R means GT30 turbine with 71mm compressor , R means rolling element or ball bearing . GT3076R = GT30 turbine + 76mm compressor and so on .

I guess to the newbies they may think a GT30 turbo ment GT30 turbine + GT30 compressor . Nup . Just because both series are GT30 does not mean any association just a number .

I can't remember which comp trim your turbos TO4S compressor wheel is . The upshot is its an outdated design but its basic size (O/D) is very similar to the GT3076R's compressor ie 76.1mm vs 76.2mm .

Your turbine is smaller that the one common to the real GT3071R and GT3076R , the difference is 56.6mm vs 60mm .

Because the turbine is identical in the two turbos you're looking at (GT3071R and GT3076R) they use the same identical series of GT30 turbine housing with either external or internal wastegate option .

Now Mafia I can't say use the 71.1 or 76.2 mm compressor type because I've not been there . I have no idea what sort of spread of power you want or how you view response vs top end rev capability . Depending on which way you jump will affect the choise of turbine housing AR ratio . As I've said I would not put the 63 housing on the GT3076R , the Garrett engineers mentioned why and I must have typed it out 10 times on various sites incliding this one .

I've also mentioned that the GT3071R is a bit fickle and likes to be spun fast and run at higher boost pressures to give off its best . My gut feeling is that it would take a .63 housing to pull up its bottom end on an RB25 but how much that chops off the top end is hard to say - should be a good punchy mid range turbo . I can repeat what I've read at Evolutionmnet (Evo Lancer site) , they reckon this turbo with the 82 housing is a little laggy and not brilliant top end but again this is on stretched 2L fours . I have not seen this turbo used with the larger .60 (vs .50) port shrouded compressor housing so cannot guarantee if it would make a positive difference - guesses yes but no proof .

If I had to guess - and thats all it is - I'd reckon the GT3076R/.82 combination may be ok IF you had a really good port job and proven mild cams ie Poncams . I would not lower the 9.0 static CR and I would only tune for and use 100 oct pump fuel . I would use the HKS cast low mount manifold becausae its better than the std one and many fabricated manifolds are not properly developed so an unknown quantity . If you are not towing a family around and driving the thing in 50 km/h traffic most of the time it may work out alright . You have to remember that your asking an originally 250 Hp engine to live with a 500Hp turbocharger so every effort needs to be taken to tease out any extra low down torque you can get .

If you cannot make your mind up use the GCG Hi Flow because people genuinely in the know really like them . I'd opt for the large or OP6 Hitachi turbine housing and thats just about as close as I can say to something that seems to be a very successful thing on a street /circuit rear wheel drive Skyline .

I'm very sorry that I can't say use combination XYZ and you'll be rapt . What I am trying very hard to do is not get people to overshoot on their engines state of tune and be bitterly unhappy with the laggy slug . My own experience is to be a little conservative and aim for 90% of perfect and trade off a bit of top end for a far more usable bottom end - its where 90% of cars are 90% of the time .

Now time for a rough and ready Stones Mac , cheers all .

[The Mafia]

hhmmm ok, well things are looking a little clearer now.

Sorry if I've been a pain disco, but here are my goals

1. Boost All in before 4,000rpm (its at that now, but this new turbo will be better anyway)

2. Boost level at 15psi ~ 18psi

3. Smooth Delivery (not too hard)

4. Power between 270rwkw and 300rwkw

5. Nice mid range torque (little bit of low lag is ok)

I'm thinking this turbo you have "built" for me would fit the bill nicely:

Real GT3076R spec (complete turbocharger number is 700382-12)

Turbine : GT30 84 trim (60.1mm inducer diametre by 55mm exducer) .

Compressor : 76.2mm 56 trim .

Cartridge number : 700177-5007

GT30 .82 IW Ex housing

.54ar Comp cover? Or maybe the .60?

I'm just trying to put a decent turbo together... Don't want to get a mismatch one again

[discopotato03]

That turbocharger comes complete with a TO4E style .60AR ratio compressor cover and with 4" (100mm) inlet . I'll post up a pic of it .

Edited November 16, 2006 by discopotato03

[The Mafia]

That turbocharger comes complete with a TO4E style .60AR ratio compressor cover and with 4" (100mm) inlet . I'll post up a pic of it .

cool, so you think that it should reach most of my targets, and be definatly better than this current one? I got it dyno'd today - 243rwkw and 420nm or torque. 18psi at 4000rpm...

heh

[Lithium]

cool, so you think that it should reach most of my targets, and be definatly better than this current one? I got it dyno'd today - 243rwkw and 420nm or torque. 18psi at 4000rpm...

Nice - that must feel fun How does it drive around normally?

Just verifying - Disco/whoever, what you are recommending is exactly what I have but with a different turbine housing? If so, I will report how mine goes with a .63a/r - and if it DOES seem like its a problem, I will just change to the .82a/r one and report how that goes.

I never knew GT3071Rs had a port shrouded version...

[discopotato03]

Well Mafia it uses a propper GT30 turbine housing and turbine , and the compressor wheel is along more modern lines . The port shrouding will work properly because its designed to by big G .

Last post edited and has pic of compressor side , do not be left alone with this pic .

It won't be a Gen 3 off idle but its a goer once it comes on song - provided the engines in good nick and its tuned properly .

Lithium - good my crystal ball batteries are about flat . They really do perform better with propper GT30 turbine housings . Like comparing a flash rim with a modern radial to the same rim with a 30 yr old cross ply tyre , both black and made with rubber but ....

Edited November 16, 2006 by discopotato03

[tridentt150v]

hhmmm ok, well things are looking a little clearer now.

Sorry if I've been a pain disco, but here are my goals

1. Boost All in before 4,000rpm (its at that now, but this new turbo will be better anyway)

2. Boost level at 15psi ~ 18psi

3. Smooth Delivery (not too hard)

4. Power between 270rwkw and 300rwkw

5. Nice mid range torque (little bit of low lag is ok)

I'm thinking this turbo you have "built" for me would fit the bill nicely:

Real GT3076R spec (complete turbocharger number is 700382-12)

Turbine : GT30 84 trim (60.1mm inducer diametre by 55mm exducer) .

Compressor : 76.2mm 56 trim .

Cartridge number : 700177-5007

GT30 .82 IW Ex housing

.54ar Comp cover? Or maybe the .60?

I'm just trying to put a decent turbo together... Don't want to get a mismatch one again

So the turbine/exhaust housing required is the 740902-2 with IW Correct???.

[Lithium]

Lithium - good my crystal ball batteries are about flat . They really do perform better with propper GT30 turbine housings . Like comparing a flash rim with a modern radial to the same rim with a 30 yr old cross ply tyre , both black and made with rubber but ....

Cheers for all your input and my slight deviation from the topic D. I didn't realise there'd be that much in the actual scroll design, had always focussed on the wheels. Live and learn.

Have you guys looked at the link I gave earlier in this thread of the dude with the GT3076R .63 on an RB25 running 16psi? His dyno plot didn't seem bad to me - aside from what looked like some queer tuning issue in the higher revs.

[The Mafia]

Real GT3076R spec (complete turbocharger number is 700382-12)

Turbine : GT30 84 trim (60.1mm inducer diametre by 55mm exducer) .

Compressor : 76.2mm 56 trim .

Cartridge number : 700177-5007

GT30 .82 IW Ex housing

.60a\r compressor cover

Well - This is what I am going to put in to order. I'm hoping to get between 270rwkw and 300rwkw, so wish me luck over the next 2-3 months.

Disco - If possible confirm the above is the best mactch for what I am planning to go for one more time, and I'm going to start this long and horrid process.

I'll be passing this exact list of specs above, and making sure they get me exactly that.

Hopefully I'll achieve some nice power.

[tridentt150v]

Real GT3076R spec (complete turbocharger number is 700382-12)

That number is only for the compressor.

If you look at turbobygarrett.com they have it:

Compressor = 700382-12

CHRA = 700177-7 and you have 700177-5007 which could be a variant.

Turbine = any of three to choose from, but the 0.82 a/r 60mm wheel, 84 trim is 740902-2.

My understanding of it is that there is no such thing as a complete turbocharger number.

I'd like to here otherwise, and Mafia I'll PM you about ordering and who your going to purchase from.

[discopotato03]

Yes Mafia , about all you could add is that the compressor cover is port shrouded and show the supplier that pic . When you get close PM me who and where from . I am not employed by or have any financial interest in GCG but I know Brett well enough to say a turbo is or isn't what I want . I can get there ocassionaly if need be .

One thing to check with Garrett or whomever is that the propper GT30 integral waste gate exhaust housings are available now here in Australia . I have seen the GT3582R type at GCG but have not eyeballed the GT30 type yet . I have not been to see Bob at Chipping Norton for some years because they're a bit further out of my way than GCG . My advise is not to pester him over trivial things because he is busy, has limited time and patience , he has been around a long time and knows his stuff .

Cheers Adrian .

[discopotato03]

Just in case you never get to see one the HKS GT3037 52T turbo has this on its ID tag .

700382-10 which cross references to CHRA or cartridge number 700177-6 or -0006 or -5006 .

The magic BCI-18C or 76.2mm 52 trim GT37 compressor option that can't be had as cheaply as a Garrett GT3076R 56T . Stupid really , so much more money for a 2mm smaller inducer compressor - but thats marketing forces for you .

Edited November 17, 2006 by discopotato03