Gt3071R V Gt3076R

[scotty nm35]

Garrett have sold out of GTX stock worldwide, there is certainly a lot of interest. There must be plenty of builds in the pipework.

It looks like you have your answer, GT3071 will be the obvious choice.

[Aberax]

I have/had the GT3076 0.82 IW, I found it a little bit laggy for my liking, but I still enjoyed it, I was pulling ~265rwkw at 15psi

You also have to remember, everyone's case/experience with these turbos is going to be different because of different set ups. So what may work well for someone else doesn't mean you are going to get the same results.

I would maybe suggest the GTX3071 or strongly suggest the GT3076. Maybe speak to Morrie at Horsepower in A Box, he has played around a little bit with the new GTX series - GTX3076 only I think, can't remember.

[bradsm87]

If U only want 270rwkw, I'd go a BorgWarner EFR 7064. It'd be insanelt responsive and make that power. If ur set on a Garrett, GT3076R 52 Trim. U do not need the 56 trim for that power level.

[Harey]

Sounds like you have 3 choices in 0.82 IW:

- 3071

- 3076 52 Trim (Disco's choice)

- 3076 56 Trim

The earlier on the list the more responsive and the less top end. The later the less responsive and the more top end. Although we are not talking huge differences between all of them, maybe 3-400rpm in response and say 20-30rwkw in top end.

[J - Rad]

What about the HKS 2835s? Would definitely be up there for one of the better 300kw and under turbos for the RB25?

[joeyjoejoejuniorshabadoo]

Joeyjoejoeshabadoo (sp) seems to be the ideal Case for 3071 (admitantly 2835 .67 or something). Making 260ish at 1 bar. Full boost about 3300. Sounds perect in theory

it is

dan (halle) has just changed from a 2835 to a 3037, so he should have his old kit for sale...

[juggernaut1]

Sounds like you have 3 choices in 0.82 IW:

- 3071

- 3076 52 Trim (Disco's choice)

- 3076 56 Trim

The earlier on the list the more responsive and the less top end. The later the less responsive and the more top end. Although we are not talking huge differences between all of them, maybe 3-400rpm in response and say 20-30rwkw in top end.

FWIW I've tried both the 3071 and 3076 52 trim with twin scroll .78 rear housing on my SR20.

With a 3.5 inch dump/exhaust (up from 3 inch) I managed to get the 3076 52 trim making more mid range than the 3071. To make it clear, the 3076 52 trim was more livelier than the 3071 at any rpm.

The 3076 52 trim is a great "no compromise" turbo compared to the 3071 for 290+ rwks'. At this level of power, traction is an issue and is probably no use making more for a rwd street car. BUT if you want more.....just add E85!!

The only downside (if you call it a downside) is that the 3076 makes alot more spool noise than the 3071 due to the surge slots in the 3076 compressor housing.

Edited March 21, 2011 by juggernaut1

[joeyjoejoejuniorshabadoo]

i wish you had done that back to back without changing the exhaust man

[juggernaut1]

i wish you had done that back to back without changing the exhaust man

Don't think things would have improved, and possibly worsened/caused damage as the 3071 was already surging when coming onto boost wih the 3 inch exhaust.

A better flowing exhaust would have possibly made it surge more when coming onto boost. The surging tells me I couldn't put any more boost into it when coming onto boost so I doubt it could make any more power in the mid range.

The surge slotted 3076 52 trim allowed me to at least match the 3071 to build boost and make significantly more mid range in the process - probably because A - it was not surging and B - it was possibly a cooler/denser intake charge with the slightly larger compressor and C - with the larger dump there was a bigger pressure differential across the turbine when coming onto boost which pulled the 3076 onto boost earlier than expected.

I.e on the dyno the 3076 52 trim was making positive pressure by around 2300rpm, 1 bar at around 3350rpm and 1.5 bar (22 psi) by 3750 rpm on a sr20.

Edited March 21, 2011 by juggernaut1

[Bunta]

I have/had the GT3076 0.82 IW, I found it a little bit laggy for my liking, but I still enjoyed it, I was pulling ~265rwkw at 15psi

I had a similar experience, Mine was a little laggy but made 300 odd RWKW at 18psi so it was pretty good. But in changing to a RB26 with twin HKS2510s I realised how much better 300 rwkw could feel!

[Harey]

I had a similar experience, Mine was a little laggy but made 300 odd RWKW at 18psi so it was pretty good. But in changing to a RB26 with twin HKS2510s I realised how much better 300 rwkw could feel!

Did you have the 56 Trim 3076?

[Harey]

What about the HKS 2835s? Would definitely be up there for one of the better 300kw and under turbos for the RB25?

Yeah just the thread starter said he wanted the 0.82 IW exhaust housing.

[Bunta]

Did you have the 56 Trim 3076?

What ever trim is the same as what HKS uses for the RB25 3037....so from my fuzzy memory I think that is the 56T. I have pics of the ID tag somewhere. If i remember i will go look it up!

[Jap_star]

cheers guys. all info is massively helpful. something like the 3037 was what i was after but the $$ isnt there for a genuine kit. im now leaning towards to 3076 with 52t, but any more helpful info is appreciated

Garrett have sold out of GTX stock worldwide, there is certainly a lot of interest. There must be plenty of builds in the pipework.

not quite, i rang MTQ and they have in stock, a touch over 2k though

The surge slotted 3076 52 trim allowed me to at least match the 3071 to build boost and make significantly more mid range in the process - probably because A - it was not surging and B - it was possibly a cooler/denser intake charge with the slightly larger compressor and C - with the larger dump there was a bigger pressure differential across the turbine when coming onto boost which pulled the 3076 onto boost earlier than expected.

I.e on the dyno the 3076 52 trim was making positive pressure by around 2300rpm, 1 bar at around 3350rpm and 1.5 bar (22 psi) by 3750 rpm on a sr20.

that sounds pretty much perfect, with a reasonable top end to boot.. this seems the best compramise between spool and top end.

while your on the dump pipe topic. ive read a split dump set up on the garret IW set ups arent ideal and a 'bellmouth' set up works better? the rest of my exhaust is a 4" magic cat and 4" cat back so that back pressure should be ok

thanks again

[scotty nm35]

not quite, i rang MTQ and they have in stock, a touch over 2k though

Yeh, I would never buy from here for that reason. For much the same price I got the GTX 3071, Tial 0.82 stainless Vband housing and a 45mm turbosmart wastegate delivered, I just have to wait for stock...

[Jap_star]

ah unlucky.

how close is the 3076 52t .82 compared to the 3037 back to back?

3037 results seem impressive. if i were to want as close as possible would it be the 52t or 56t?

thanks

[wolverine]

Roughly speaking the 52trim 76mm compressor is about 475hp vs 56trim 76mm comp being 500hp.

Like I said it is a bit of an each way bet between the GT3071 and GT3076 (both usually come as 56trim versions respectively).

[Jap_star]

So in the end much of a muchness and either should do the job? Been doing some research this arvo. Plenty of info on the 76 with 56 trim on RB not alot with the 52. so if it's comparable to the 3037 (even with the rear housing difference) then there's also alot

[juggernaut1]

while your on the dump pipe topic. ive read a split dump set up on the garret IW set ups arent ideal and a 'bellmouth' set up works better? the rest of my exhaust is a 4" magic cat and 4" cat back so that back pressure should be ok

thanks again

I've had the CES split dump pipe on the stock s15 turbo. Never had it on a dyno but it was a fantastic upgrade from a seat of the pants feel.

However, depending on the quality of the split dump and how soon after the slit dump merges back into the main exhaust can give varying results (good and bad). My current setup has the external gates merging back in just before the cat i.e. merge it back in as late as possible. On IW setups there have been mixed results as I previously mentioned. I think the concensus is to go a quality bell mouth setup.

Edited March 21, 2011 by juggernaut1

[HEKT1K]

So in the end much of a muchness and either should do the job?

I'm no expert, but this ^ is kinda what i've gleaned from this thread.

I have a 3071 56T .82 and love it. Not having had a 3076 or any other Garrett turbo i suppose it's easy to say that, however i don't think the differences in trim and comp wheel size are really worth fussing over *too* much.

(This all assumes that the rest of your setup is sorted)