Conflicting Gt3076r Specs, Please Help

[darrinspencer]

Also a site sponsor on here has told me the gt3076r does not come with anti surge inlet on the compressor any more.

It now comes with a standard 4 inch smooth bell mouth inlet

[conan7772]

Also a site sponsor on here has told me the gt3076r does not come with anti surge inlet on the compressor any more.

It now comes with a standard 4 inch smooth bell mouth inlet

Beauty, if that's true.

That's exactly what I originally ordered.

Apparently the slots reduce high rpm efficiency. Anyway , a properly fitted and quality BOV does the job.

I wonder if HKS will follow.

[juggernaut1]

How does a BOV replace the effect of anti-surge slots when these anti surge slots minimise compressor surge when the turbo is spooling under acceleration.

In this instance compressor surge happens when the turbo is spooling too fast for the engine to swallow the airflow it is providing i.e. at low rpm. As a result the air backs up in the turbo system and ends up coming back out of the compressor intake. This type of surge is more prone to happening when your using relatively smallish ex a/r's on biggish compressors as the small ex a/r is more likely to spool the compressor faster at low engine rpm which is usually when the problem arises. The anti-surge slots are effectively a bypass system.

PS I just picked up a 3076 and it had the anti-surge slots.

[Haines]

I got the .73 housing on mine and it limits the power for sure

later on ill try and mod it to a .82 4 bolt garrett housing and an external wastegate setup

I tried, it failed ill move on

[conan7772]

How does a BOV replace the effect of anti-surge slots when these anti surge slots minimise compressor surge when the turbo is spooling under acceleration.

In this instance compressor surge happens when the turbo is spooling too fast for the engine to swallow the airflow it is providing i.e. at low rpm. As a result the air backs up in the turbo system and ends up coming back out of the compressor intake. This type of surge is more prone to happening when your using relatively smallish ex a/r's on biggish compressors as the small ex a/r is more likely to spool the compressor faster at low engine rpm which is usually when the problem arises. The anti-surge slots are effectively a bypass system.

PS I just picked up a 3076 and it had the anti-surge slots.

Surge can happen under load yes but mainly off throttle.

I wonder why six cylinders are more prone than fours

Anyway...

Hence the need to stay with the Garrett 0.82 rear

[juggernaut1]

Surge can happen under load yes but mainly off throttle.

I wonder why six cylinders are more prone than fours

Anyway...

Hence the need to stay with the Garrett 0.82 rear

This is the surge I'm referring to - which is the most dangerous and is what the surge slots on the 3076 and the like are designed to reduce - No BOV will help you here. Haha...and its a skyline.

You can hear the air backing out of the turbo inlet and being chopped by the compressor blades whilst the turbo is still being driven under load - nasty.

Edited May 31, 2009 by juggernaut1

[darrinspencer]

PS I just picked up a 3076 and it had the anti-surge slots.

from where?

what size rear housing?

Price?

[juggernaut1]

I got it through PJ's Quick Bits on NS.com (forum sponsor) $1,350 delivered to Perth - without the rear housing (as I'm upgrading my 3071). Obviously pick up would be cheaper. Just checked my invoice - it was $1,280 without delivery/insurance.

I couldn't get one in WA - MTQ in WA had 40 on backorder available in June. When I rang they said everyone is throwing these turbos (3076's) on all sorts of motors - hence the demand.

Edited May 31, 2009 by juggernaut1

[discopotato03]

No the port shrouded compressor housing is not out of production , I've never ever seen a factory GT3076R with a non port shrouded 0.60 A/R large boss T04E compressor housing .

I believe there was a version marketed by HKS that had a std sized T04E 0.60 A/R comp housing and off the top of my head the inlet barb was 2.75" rather than 4" like the port shrouded one .

I think confusion arises because the GT30/T04S version of these turbos uses a 0.70 A/R T04S comp housing - like a GT3582R has . These housings have the large non port shrouded bell mouthed inlet bosses .

As always , check the turbos ID tag . If it doesn't say 700177-7 or -6 it ain't a real GT3076R with the GT37 series compressor wheel . The "37" in GT3037 is what makes it a real GT3076R .

Clear as mud I know , in the old numbering system 30 and 37 meant GT30 turbine with GT37 series comp wheel .

With the current system 30 and 76 means GT30 turbine with 76mm diameter compressor .

Trouble is that some T04S comp wheels are 3" or ~ 76mm OD as well .

Long story short , count the number of compressor blades (6/12 or 7/14) and note the A/R number cast into the comp housing . 6/12 blades + 0.60 A/R generally means the real one along with the -7 or -6 CHRA prefix .

7/14 + 0.70 A/R usually means a GT30/T04S .

If it has 6/12 blades and the larger 0.70 A/R comp cover with a -14 CHRA prefix it's most likely a GT3082R ( GT3040R in old speak) .

A .

[Lithium]

Also a site sponsor on here has told me the gt3076r does not come with anti surge inlet on the compressor any more.

It now comes with a standard 4 inch smooth bell mouth inlet

I was given this same run around a few years ago when trying to buy my true GT3076R - everyone kept pointing me at the T04S covered version with the different compressor wheel, I even provided them with the CHRA reference to make sure they gave it. I tried a guy who uses an Australian supplier they swore by (SAU Sponsor too I believe) and they at best glanced at it and told me "That version has been phased out, this is the newer/better one". Anything to make a sale, eh?

I ended up buying my REAL GT30R from ATPturbo.com, never looked back.

[mad082]

Had the gt3076r with 0.7 rear housing (Had the id tag 3037) So that core with the Garrett Gt30 anti surge front housing and AVO rear housing to suit rb25det.

Couldnt push more then 250rwkw on 20psi without major det, dont think that rear housing is any good, id stick with the garrett one or got for an hks gt3037 pro s

i fitted a 3037 badged 3076 with the 0.62 or 0.64 skyline pattern rear housing (can't remember which one) to a mates 33 a year or 2 ago and with a basic tune and about 17psi it made 251kw and the motor wasn't the healthiest specimen either. the turbo was from GCG i'm pretty sure

No the port shrouded compressor housing is not out of production , I've never ever seen a factory GT3076R with a non port shrouded 0.60 A/R large boss T04E compressor housing .

I believe there was a version marketed by HKS that had a std sized T04E 0.60 A/R comp housing and off the top of my head the inlet barb was 2.75" rather than 4" like the port shrouded one .

I think confusion arises because the GT30/T04S version of these turbos uses a 0.70 A/R T04S comp housing - like a GT3582R has . These housings have the large non port shrouded bell mouthed inlet bosses .

As always , check the turbos ID tag . If it doesn't say 700177-7 or -6 it ain't a real GT3076R with the GT37 series compressor wheel . The "37" in GT3037 is what makes it a real GT3076R .

Clear as mud I know , in the old numbering system 30 and 37 meant GT30 turbine with GT37 series comp wheel .

With the current system 30 and 76 means GT30 turbine with 76mm diameter compressor .

Trouble is that some T04S comp wheels are 3" or ~ 76mm OD as well .

Long story short , count the number of compressor blades (6/12 or 7/14) and note the A/R number cast into the comp housing . 6/12 blades + 0.60 A/R generally means the real one along with the -7 or -6 CHRA prefix .

7/14 + 0.70 A/R usually means a GT30/T04S .

If it has 6/12 blades and the larger 0.70 A/R comp cover with a -14 CHRA prefix it's most likely a GT3082R ( GT3040R in old speak) .

A .

doofy got a 3076 from a site sponsor the other day and it had the unslotted 0.70 A/R front on it so i said to him that it might be a 3082 but when he measured the ID it wasn't as big as the 3082. can't remember what exhuast housing he got, but it was 0.8 something

[DRD-00F]

This is the real one .

http://www.turbobygarrett.com/turbobygarre...R_700382_12.htm

If them as says you can't get these insists look elswhere .

Cheers A .

Gt3076r the avo 0.7 rear 3037 core

Gt3076r the Garrett one, this is what u want

Also a site sponsor on here has told me the gt3076r does not come with anti surge inlet on the compressor any more.

It now comes with a standard 4 inch smooth bell mouth inlet

This is what I was told as well

No the port shrouded compressor housing is not out of production , I've never ever seen a factory GT3076R with a non port shrouded 0.60 A/R large boss T04E compressor housing .

I believe there was a version marketed by HKS that had a std sized T04E 0.60 A/R comp housing and off the top of my head the inlet barb was 2.75" rather than 4" like the port shrouded one .

I think confusion arises because the GT30/T04S version of these turbos uses a 0.70 A/R T04S comp housing - like a GT3582R has . These housings have the large non port shrouded bell mouthed inlet bosses .

As always , check the turbos ID tag . If it doesn't say 700177-7 or -6 it ain't a real GT3076R with the GT37 series compressor wheel . The "37" in GT3037 is what makes it a real GT3076R .

Clear as mud I know , in the old numbering system 30 and 37 meant GT30 turbine with GT37 series comp wheel .

With the current system 30 and 76 means GT30 turbine with 76mm diameter compressor .

Trouble is that some T04S comp wheels are 3" or ~ 76mm OD as well .

Long story short , count the number of compressor blades (6/12 or 7/14) and note the A/R number cast into the comp housing . 6/12 blades + 0.60 A/R generally means the real one along with the -7 or -6 CHRA prefix .

7/14 + 0.70 A/R usually means a GT30/T04S .

If it has 6/12 blades and the larger 0.70 A/R comp cover with a -14 CHRA prefix it's most likely a GT3082R ( GT3040R in old speak) .

A .

So with everything that has been said in this thread, wtf do I have?!

Don't know the ID tag (it's at home) but measured the comp wheel and it was the size mentioned by Garrett to be the 3076... My biggest problem was no anti surge slots, but they can be drilled in the future if need be...

[darrinspencer]

Just spoke to a supplier and they have stock of the t3 IW .82 rear housings.

The supply problem is with the actual turbo. They are on back order.

Waiting for them to call back when they will be available.

Otherwise I will give up on the aussie guys and go to Atpturbo.

The extra long manifold studs needed for the spacer plate are hard to find as well.

Can mild steel studs 65mm long, but no hi tensile ones.

[Cartman]

Gt3076r the avo 0.7 rear 3037 core

Gt3076r the Garrett one, this is what u want

its interesting to see that is where that 5stud garrett housing came from, i've seen them used in highflow setups before had always wondered what housing it was.

[conan7772]

This is the surge I'm referring to - which is the most dangerous and is what the surge slots on the 3076 and the like are designed to reduce - No BOV will help you here. Haha...and its a skyline.

You can hear the air backing out of the turbo inlet and being chopped by the compressor blades whilst the turbo is still being driven under load - nasty.

[/quote

]

Nasty !

Interesting...

Wouldn't you expect Garrett would port shroud the bigger 0.7 comp rather than 0.6 as it's the larger comps more likely to surge ?

Also curious to know what differences the 0.6 and the 0.7 comp cover would have between eachother with the same wheel, trim and rear.

Or would the 0.7 have the 82mm wheel ?

Edited June 1, 2009 by conan7772

[conan7772]

I've just ordered a GT3076r for an RB25/30

Comp 0.6A/R

Trim 56

Turbine 0.82A/R

Recently been advised this configuation isn't available, only with a 0.86 A/R rear.

Who makes the 0.86 ?

If I strictly want the 0.82 rear then trim has to be 52 and Comp cover either 0.5 or 0.7 A/R.

Can anyone please confirm these specs are correct.

Cheers.

Found it.

The 0.86 rear is an ATP set up with the 90 trim GT3071 turbine.

They call it the GT3076R-WG 500hp

[SLAPS]

My Garrett internal gate housing has 82 stamped on it.

Make sure you get the xr6t style IW Garrett housing as I've seen some 'really' poor results from the .7 R34/VG30 style rear housings.

[Dale FZ1]

Wouldn't you expect Garrett would port shroud the bigger 0.7 comp rather than 0.6 as it's the larger comps more likely to surge ?

Also curious to know what differences the 0.6 and the 0.7 comp cover would have between eachother with the same wheel, trim and rear.

Or would the 0.7 have the 82mm wheel ?

Don't look at the compressor cover as being a determining factor for surge - that housing is pretty much a carrier for the air being forced in to the engine. The overall size/spec of the turbine, and the size/specification of the impeller within the comp housing are what I understand will dictate the general flow characteristics of the turbocharger. Force the compressor to turn fast/hard/early and you can get to the point of trying to push more air than the engine can ingest at certain load/speed ranges. That leads to the rapid oscillating column of air and the surge condition that gives the chuff/chuff / chirp/chirp noise.

Changing from a 0.6 A/R to 0.7 A/R comp housing won't change a whole lot. That is a size ratio only, it does not describe an absolute size. When that number does become relevant is when he housings were designed within the same family. Then the bigger number indicates an ability to pass a larger air mass.

An example of this would be the Ford XR6 GT3582 - 1.06 turbine, 0.50 compressor housings. I've seen people swap in a 0.70 comp cover to provide a bit more top end flow capacity. Also compare the 0.82 GT35 turbine housing, and it will flow less air mass than the 1.06 - but it will spin the turbine faster/earlier and give a different sort of response.

Garrett and Borg Warner offer some very good tutorials to explain all of the above, with pictures to assist.

Check Discopotato03's post and it's quite clear that just because something called a GT30 has a 0.70 A/R comp cover does not automatically mean it is a GT3082. It could well be a 7 bladed TO4S based GT3076 (which I think could not be legitimately called a GT3037 because the comp wheel does not belong to the 37 series). Point being you have to look at the signs, and source the CHRA spec sheets. Check out the number of blades, read the part number and cross reference it to what the manufacturer badged it as.

The picture posted by DRD-OOF shows a 7 bladed comp wheel - that should be a fairly strong indicator as to what he has got. Technical differences aside, I think it would run pretty well. The main disadvantage that I see is lower compressor efficiency at high speeds that leads to higher inlet temps and a touch lower absolute power output from the engine.

[discopotato03]

What the port shrouded compressor covers do is make these GT3076R/GT3037S turbos a wider ranging unit .

They cope better with smaller ratio turbine housings than a non port shrouded unit can .

For example , HKS sold suitable turbine housings for these GT30 based turbos down to 0.61 A/R . That's whats needed to get a 500+ Hp capable turbocharger to spool up on say a CA18 or RB20 , these engines in basic street tune may or may not be able to swallow 500 Hp's worth of air and the port shrouded compressor cover helps cycle/recycle the extra air that the engine may not feel like using .

I get the feeling that compressor covers/housings on these GT3071R/GT3076R/GT3082R/GT3582R turbos are a bit of a mystery family wise .

Basically GT3071R's normally have a T04E family bell mouthed 0.50 A/R comp housing .

GT3076R/GT3037's a T04E 0.60 A/R housing , PS'd on GT3076R and GT3037"S" and plain on GT3037 .

GT30/T04S with the 7/14 blade compressor , 0.70 A/R T04S housing to match its T04S comp wheel .

GT3040R/GT3082R , these also have the larger family T04S 0.70 A/R comp housing .

GT3582R generic , as above the T04S 0.70 A/R housing .

GT3582R-XR6T . This one's unique because Ford opted for a 0.50 A/R T04"E" comp cover basically like a GT3071R uses but with the small std non PS'd inlet boss .

It also has a large ratio 1.06 A/R IW turbine housing on it . My guess is that Ford didn't want to pay anyone to develop a close matching turbocharger for the "250 Cu with an education" engine . So they opt for an off the shelf Garrett GT3582R cartridge and a big ratio turbine housing (which they did have developed here in Aus I'm told) and a small family and ratio comp housing for that 82mm GT40 compressor .

They weren't looking for a lot of airflow or boost in the XR6T because it doesn't take heaps of either to make a 4L DOHC 24V engine feel torquey - in relation to their bitza V8 .

So lowish pressure in the hot side of a soft .. tuned 4L 6 and a little extra wind in the cold side .

Yes people do fit the larger T04S 0.70 A/R comp housing and adapter ring to original XR6 spec turbos though there is a direct fit comp housing from Garret that fits the XR6 variants T04E adapter ring - and has the 2" outlet like the std XR6 turbos housing - T04S is usually 4" in and 2.5" out .

Ah I forgot to mention , how could I forget , that Garrett is now selling model specific GT3071R's and GT3076R's in twin scroll twin integral waste gate for for the current Mitsy Evolution 10 Lancers . Burger with the works meaning 0.73 or 0.94 A/R TS TIW (TWIG = twin waste gate internal gig) turbine housings and 0.60 A/R comp housings . Sadly they use the Mitsy mounting flange on that turbine housing but if you are up for a custom exhaust manifold ....

A .

[DRD-00F]

How confusing.

Is it worth kicking up a stink for the correct spec 3076 with port shrouded cover? Or not worth my trouble?