Whos Interested In The Gt3076r/gt3037 In 52 Trim ?

[GTScotT]

IMHO the flex fuel will let the .63 sit on the upper limits and net you the magic 300.

I am all for this move, I think its going to be great if the rest of the car is up to the task.

Just make sure you get the right housing.

[Lithium]

I only mean it making that kind of power on E85 type fuels. I also prefer the idea of something smaller than a 76mm exducer with a .63 turbine.

[Dale FZ1]

I’d consider the set performance parameters

GT30 turbine

~300kW output

best transient response, GT-RS as a benchmark

max torque at lowest rpm

The 0.63 housing is a compromise in itself, depending on hardware and fuelling choices. The two blokes I know that have used the 0.63 option on a GT30 both went with internal gates. Both experienced boost control issues in that they could not successfully run boost levels under 18-19psi. That to me says there are issues in bypassing sufficient gas via the gate to control turbo speed. Maybe no issue if the target output is 300kW because that’s the sort of boost required to hit that mark. I feel it’s about balancing things, because if the easiest gas path through the turbine assembly is via the turbine exducer then the gate is under-engineered and a potential problem. Best option to deal with that is via a reasonably engineered and large capacity external gate that gives the boost control Lithium suggests. A 1.4 bar mid range tapering to 1 bar @ 6500 would certainly give a huge shove in the 3-5000rpm range, if a little flat in comparison above there. With good (and effectively tuneable) boost control he could play and get what best suits his preferences.

Disco’s thread on the TR30 unearthed a few photos of manifold/gate/turbo setups that I think have relevance to this GT30 unit and performance targets. The TR30 runs smaller exducer dimensions (smaller trim size) so the venting capabilities via the gate are addressed properly by good design engineering. I think it’s not hard to connect the dots here, and use the experiences gained in a pretty hard-core environment.

As the 0.63 housing provides an increasing obstruction to gas flow as rpm and boost (mass flow) increases, the potential for reduced scavenging and heat retention also give cause for concern about reduced knock threshold for the engine at those high rpm. I agree that Disco’s use of ethanol blend fuel will provide resistance to knock not reliably available via pump 98.

The GTX67mm compressor would certainly be an interesting oddity that would be difficult to predict until flow maps and dimensions are known, and even looking at how the rotor looks in comparison to the GT76mm and the GTX71mm. My thoughts would be that it would be more of the same as the GTX71. Higher rotor speeds before the thing pumps decent air mass, and a small but detectable difference in where/how it responds to a whiff of throttle on steady inclines.

I don’t see the GTX67 as offering any likely practical benefit, so the existing 52T GT3076 would get the nod. The fact that Adrian already owns that unit says it would involve a dive into the unknown, with a cost associated. The slightly reduced throat size and flow potential of that unit (compared to the 56T GT3076 or the GTX3071) won’t prove to be detrimental, and I reckon this compressor spec will do close to “best match” for his performance targets and operation characteristics.

All the above is just an opinion, but standing in Disco’s shoes that is the direction I would go.

[discopotato03]

I just got this turbo out for a look over and that 0.82 GT30 turbine housing sure has a large passage through it , not hard to see why its not doing a lot under 3000 revs . As I said don't know if the 52 trim size makes any difference here . Damn Garrett for not making a 0.73 AR size instead of 0.63 AR .

The actuator is Pn 432225-14 and the invoice reckons its a 14.7 lb big can one .

I suppose running it as is would prove if the turbine housing is too big for me ...

The post above came through just as I was about to press send .

A .

Edited March 13, 2013 by discopotato03

[Lithium]

The GTX67mm compressor would certainly be an interesting oddity that would be difficult to predict until flow maps and dimensions are known, and even looking at how the rotor looks in comparison to the GT76mm and the GTX71mm. My thoughts would be that it would be more of the same as the GTX71. Higher rotor speeds before the thing pumps decent air mass, and a small but detectable difference in where/how it responds to a whiff of throttle on steady inclines.

I don’t see the GTX67 as offering any likely practical benefit, so the existing 52T GT3076 would get the nod. The fact that Adrian already owns that unit says it would involve a dive into the unknown, with a cost associated. The slightly reduced throat size and flow potential of that unit (compared to the 56T GT3076 or the GTX3071) won’t prove to be detrimental, and I reckon this compressor spec will do close to “best match” for his performance targets and operation characteristics.

All the above is just an opinion, but standing in Disco’s shoes that is the direction I would go.

I'm like you in that I am totally unsure of what to expect from the GTX-67, I actually liked the fact it would run higher shaft speeds - under the assumption (honestly don't know what to expect in real world) that they will always "windwill" at a higher speed, and also the turbine will operate more efficiently at higher RPM - one of the reasons I am actually happy with the .63a/r housing in this case. It will have a fair amount less inertia than the 76mm which I am assuming that combined with the higher efficiency mm2 for mm2 will more than outweigh the greater actual rpm it needs to accumulate. No idea how it'd really feel, just conjecture.

GTX3076R Compressor map:

I do however think the 52t should be REALLY liveable, would make for a nice street car and attain DP's target power levels without too much strain. No brainer advantage that it is right there, too.

[jet_r31]

I just got this turbo out for a look over and that 0.82 GT30 turbine housing sure has a large passage through it , not hard to see why its not doing a lot under 3000 revs . As I said don't know if the 52 trim size makes any difference here . Damn Garrett for not making a 0.73 AR size instead of 0.63 AR .

The actuator is Pn 432225-14 and the invoice reckons its a 14.7 lb big can one .

I suppose running it as is would prove if the turbine housing is too big for me ...

The post above came through just as I was about to press send .

A .

If you wanted a .73 ..I thought Kando dynamics do a T3 Gt30 .73 housing...

.63 on E85 would meet your goals i would think anyway...

cheers

darren

Edited March 13, 2013 by jet_r31

[Dale FZ1]

Performance map for the GTX67mm suggests it is spec'd for high boost (>2bar) applications. Interestingly I see the current Garrett catalogue also shows a GTX2860 (rally), complete with marked choke point on its map for a 34mm restrictor. Again, specs show good flow capacity at very high PR. Seems like a bit of targeted marketing.

With a bit more info at hand I'm confident Disco's existing spec will probably be the best for his aims.

Given the 0.82 housing is also in the parts inventory, the pragmatic view would be to give it a run. I didn't think that the "feel" was much different, just that the 0.63 shifted the curve to the left so it all happened sooner (and tapered off sooner).

[wolverine]

I reckon 200rpm more or less on the clock and you won't give a shit.

Whilst on paper the 0.63 might be ok if boost control doesn't prove to be a pain in the arse I would still use the 0.82 since it is already in possession and will flow whatever the compressor can throw at it efficiently.

Although I would have a good long think about driving the car around with the GT-RS since it is just a street car. In 12-18mths time lose your mind and then you can burn thru some money again like a good skyline owner.

[jet_r31]

I was thinking that maybe the .82 may produce a more progressive power curve which would be better for a "street" radial tyre

so even though it comes on a little bit later,and woudn't look as pretty on a dyno plot , the power curve may be nicer for grip...

cheers

darren

[scotty nm35]

Something Stao mentioned recently and I have noticed first hand, the larger AR turbine housings actually increase response as there is more exhaust energy to spin up the compressor, it all just happens a little later. The gt30 .82 is the happy medium for a 2.5 imo. (but my car runs variable cams which increases the midrange punch.) Without vct I would be chasing anything that can decrease spool time.

[discopotato03]

My lump has a few alterations like Poncams and a slightly higher static CR , mild porting and slightly ovesized exhaust valves . Headgasket I can't remember but the head had stainless wire rings fitted just behind the gaskets fire rings .

Manifolds were port matched too .

I opted out of the GTX3067R because it has nowhere to grow if its a bit lacking . A few people said that using a 0.82 GT30 turbine housing on one would add lag for no good reason .

Also as mentioned you can go up or down (63/82) on turbine housing size with a GT3076R and make them livable on RB25s AND RB30s . I think you'd be painted into a corner if you tried to put a GTX3067R on an RB30 and I'd like to keep my options open .

A .

[Lithium]

Excellent - I like where your head is at. I am interested to see how the 52T GT3076R goes, and hope it works out well for you.

[34GeeTeeTee]

The mid range on my GT3037 is huge, the punch is pretty impressive... Although I would love a bit more response... After a LOT of thought about changing turbos recently I think I'll stick with what I have, it sounds good, makes good power and is very street able... Mine is 56T

[AngryRB]

ill be bolting on a 0.63 external version of the GT3037, 56trim, to go with the poncams and E85, will be interesting to see how responsive it is and how much top end , hoping for massive area under the curves on 20psi

Edited March 13, 2013 by AngryRBGTX

[wolverine]

Oooh we have a guinea pig for the 0.63 a shame it isn't internally gated.

[GTScotT]

Simon s14 already did .63 ewg, he even moved it to his RB30 lol

[jet_r31]

4bidn1 did it a long time ago in his stagea, think its in the dyno thread in stagea section, 3076 56T .63 , 38mm ext gate on exhaust housing on stock

mani , 260 ponnies, e85 and reverse flow cooler

cheers

darren

[discopotato03]

Quick update cause I'm v busy ATM . That SR20 with the FR T4 manifold and Garrett T4 0.63 AR housing / GT3067R cranked out almost 460 wheel Hp and 340 ft/lbs of torque at 20 pounds of boost . This was on non specified "pump gas" so E70/E85 would do a bit better .

Compared to his ext gate GT2871R 0.73 AR setup the X was up 60 hp in the middle and about 120 up top .

Will ask more later , cheers A .

[Dale FZ1]

ill be bolting on a 0.63 external version of the GT3037, 56trim, to go with the poncams and E85, will be interesting to see how responsive it is and how much top end , hoping for massive area under the curves on 20psi

Any ideas on manifold/gate setup you intend to use? Be sure to post up some pics of the setup and at least link your results into this thread so we get some continuity and a bit of direct comparison to what Disco's setup does.

[Lithium]

Pretty happy with GTX3067R results I am seeing, was hoping that it might perform like initial impressions suggest it will but wasn't totally sure if the GT30 turbine would allow it. Looks like it does :-)

Gt2871r getting schooled by GTX3067R: http://www.nissanroadracing.com/showthread.php?t=4395&page=3