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

[Cubes]

Personally its the way I'd go if I was after that power level.

Cams + GT3071r 56.8mm turbine wheel and .7 RB IW housing. Simon was running the same cams as myself (805c tight regrind ~265duration 8.9mm lift).

As I mentioned earlier he was saying before the cams it was laggy and not all that impressed with the setup. I went for a spin in it after cams and was quite impressed.

I've got a coup ale of dash vids of mine before and after the cams on the same boost level ~1bar. First/second ramps up so much quicker after the cams. Just for that affect lone I'd look at the cams.

[zebra]

cool,

so cams it is then .

Im gonna speak to tighe again and see about pricing, last time i spoke to them they quoted 1000bucks for regrinds, wheres i think you said they were around ~400ish

im gonna go with the 3076 as i want a little bit of head room to move if i decide to go with E85 once it becomes more readily avaliable, and the little extra lag ill live with to tame the power delivery a little bit, but I will go with the .7ar rb exh housing. for easy of fitment, (basicly is cdf having to pay for a custom dump and getting the car to an exhaust place to do it,

also does anyone remember the rough lenghts of oil and water lines they used? HPIAB does braided kits so ill prob just go with one of those (350mm oil feed line length)

[Cubes]

The $380 price is if you have a set of std GTR cams to start with.

$1k is grinding up a set of billets.

As for water/oil lines I dropped through pirtek and used bundy tube. ~$40 each line and its done. So ~120 all up.

Bundy tube is the same metal tuning Nissan used from factory. Can be bent relatively easily.

[zebra]

ahk sweet,

im guessing the GTR cams wont work with the NVCS though

I didnt even think of using bundy tube. im guessing its ~40 with the fittings installed.

cheers Cubes

[NYTSKY]

Just thought i would add a comment,

I have upgraded to HKS 256/264 cams and i have drained my fuel tank as i will be running the car on E85

With a GT3076 .82 and all my other supporting mods i think 320rwkw at 20psi will be achievable.

My tuner will be installing a 200L tank at his shop filled with E85, mostly for tuning purposes. And the occasional customer who needs 5L to get to a E85 station

[GTScotT]

I hate to dig up an age old thread, yet Mafia never did end up updating us with info on what turbo was used for 314rwkw? was it the original one making 240rwkw a few pages earlier?

After weeks and weeks of GT30 reading im KEEN AS MUSTARD to know just what the final changes were and how it changed the cars character.

[Dale FZ1]

GT3076, CHRA 700177-5007, with a Garrett IW housing 0.63 A/R.

That spec has the 0.60 A/R ported shroud compressor, and 6 x 2 blade impeller.

One of very few to run that spec turbine housing, and I can confirm it makes its power earlier than the 0.82 - but it also signs off a little earlier. I do believe that water/meth is a big aid in getting the best from this spec turbo.

Best if you heard it direct from Mafia, but having driven it, it's certainly got some balls.

[Don Dada]

Check this out

http://www.skylinesaustralia.com/forums/30...es-t167572.html

[Don Dada]

GT3076, CHRA 700177-5007, with a Garrett IW housing 0.63 A/R.

That spec has the 0.60 A/R ported shroud compressor, and 6 x 2 blade impeller.

One of very few to run that spec turbine housing, and I can confirm it makes its power earlier than the 0.82 - but it also signs off a little earlier. I do believe that water/meth is a big aid in getting the best from this spec turbo.

Best if you heard it direct from Mafia, but having driven it, it's certainly got some balls.

Yeh too bad we don't have more results with the 3076 in its .63 Garrett form.

Dale fz1 i remember u mentioned some time before that when u drove Mafia car the feeling was not a sudden on-off transition into boost.

Obviously it would not give u that free flowing power out top end but i would say that your choice of the turbine a/r would depend on how much pwr u want to make in the first place.

Maybe on the 314rwkw it would have felt like it was falling flat on top, but with say...280rwkw would u think it would have this same feeling???

If u look at Mafia's graphs the pwr does not drop off at the top of the rpm range either and i know the wmi has a part to play in this but it still shows us what the turbo is capable with its small .63 back end.

I see alot of guys going with the .82 on rb30 builds and i can understand that for the added displacement, but i feel that if u only want up to 280-290rwkw the 3076 .63 is the way to go.....even better than the 3071 .82 which we see will be at its absolute limit on a stock rb25

[Lithium]

I don't agree, I am personally not a fan of the .63a/r GT3076R - WMI is "cheating" when comparing with normal outright pump gas results. Has anyone tried a GT3071R with WMI? Imho, if you want a bit more response than a GT3076R and aren't worried about making less power then you should just got a GT3071R... the inbetween is probably not worth it.

I've had a .63a/r GT3076R, and had first had experience as to what its like having a hot side which is restrictive for what you're doing and in my opinion the slight bit more zest below 3000rpm is well not worth it. Above 3000rpm I reckon you'd be doing well to tell the difference between the .82a/r and a .63a/r. Another thing, the T4 twin scroll 1.06a/r GT3076R is available now... best of everything imho

[discopotato03]

I'm hoping the 52 compressor trim version of the GT3076R proves to be a little more responsive than the 56T version and works well with the Garrett 0.82 A/R turbine housing .

On paper HKS quote the 48T 3037 as having the same power/airflow as the 56T GT2835 (71.1mm comprressor) so in theory the 52T 76.2mm compressor should split the difference between 56T 71.1 and 56T 76.2mm GT compressor ends .

I won't be the first to use a 52T GT3076R/3037 and the word is that some people have been ordering these turbos here recently . For my part I'll be keen to see how they pan out and personally I wouldn't compromise it with the 0.63 housing . Maybe if we could get the 48 comp trim version but still a little limiting I feel .

Mongrel Garrett should really be thinking along the lines of a 78T turbine option for GT30 and GT35 turbines , the generic 84T size is reasonably big and free flowing but not the easiest things to get response from . If they can do it on GT37 and GT40 turbines they can do it for GT30's and GT35's .

Note Holset and BW don't always use large trim turbines .

Cheers A .

[juggernaut1]

I'm hoping the 52 compressor trim version of the GT3076R proves to be a little more responsive than the 56T version and works well with the Garrett 0.82 A/R turbine housing .

On paper HKS quote the 48T 3037 as having the same power/airflow as the 56T GT2835 (71.1mm comprressor) so in theory the 52T 76.2mm compressor should split the difference between 56T 71.1 and 56T 76.2mm GT compressor ends .

I won't be the first to use a 52T GT3076R/3037 and the word is that some people have been ordering these turbos here recently . For my part I'll be keen to see how they pan out and personally I wouldn't compromise it with the 0.63 housing . Maybe if we could get the 48 comp trim version but still a little limiting I feel .

Mongrel Garrett should really be thinking along the lines of a 78T turbine option for GT30 and GT35 turbines , the generic 84T size is reasonably big and free flowing but not the easiest things to get response from . If they can do it on GT37 and GT40 turbines they can do it for GT30's and GT35's .

Note Holset and BW don't always use large trim turbines .

Cheers A .

I for one ordered one from GCG before Christmas (with the bell mouth insert) and will team it with the twin scroll .78 ex housing that has been subject to extrude honing and will swap it over from the 3071/.78 setup. I just felt that a 3076 56 trim will not realise its full potential with the .78 ex housing and didn't want to suffer the consequence of additional lag for a power figure that would be capped by the ex housing.

Possibly if I was running E85 I would have fitted the 3076 56 trim as this fuel seems to somewhat shed the effects of smaller housings. But until E85 beomes commercially available in WA, the 3076 52 trim with the honed .78 ex housing seems to make more sense as an overall package on the little SR.

Edited January 7, 2010 by juggernaut1

[GTScotT]

I wonder just how much more urgent the boost delivery will be on the 52T vs the 56T.. and how much it will hold back outright power if at all.

through all my reading I am convinced that the 3076 56T .82 is the way to go for me but cannot find enough info on how it comes on boost.. which is why im considering the 52T option instead.. trying to cover myself for offboost twisty run faux pas.. coming from an evo to a skyline its a worry.. ARGH

[Dale FZ1]

I am personally not a fan of the .63a/r GT3076R

I've had a .63a/r GT3076R, and had first had experience as to what its like having a hot side which is restrictive for what you're doing and in my opinion the slight bit more zest below 3000rpm is well not worth it. Above 3000rpm I reckon you'd be doing well to tell the difference between the .82a/r and a .63a/r. Another thing, the T4 twin scroll 1.06a/r GT3076R is available now... best of everything imho

Generally speaking, I would agree Lithium.

The bigger turbine A/R certainly allows a stock RB25 to breathe as rpm rises, and gives one a lot of free revving zest (if that makes sense to those who haven't experienced it??).

For bottom end and mid range urge, the 0.63 isn't a bad thing (quite potent in fact), but you'd then need to wonder if a full HKS GT-RS kit would be more suitable and probably near as quick in most situations.

One of the tricks to a good outcome is having usable torque to suit the available gearing and speeds the car will be operated at.

Only other thing I could add is that I enjoyed Mafia's car but would probably still go the 0.82 spec unless I could afford a split pulse setup. Then the price difference might lead me towards an RB30DET as a viable option...

[Lithium]

through all my reading I am convinced that the 3076 56T .82 is the way to go for me but cannot find enough info on how it comes on boost.. which is why im considering the 52T option instead.. trying to cover myself for offboost twisty run faux pas.. coming from an evo to a skyline its a worry.. ARGH

I don't have my big can actuator yet, but I do have an AVC-R - if you have any tests you would like me to do which show rpm/speed/boost level I can try and get someone along for a blat with me and film the screen doing whatever pulls you would like to give a rough idea?

[discopotato03]

There probably isn't much in it (2mm/80 thou) but their insert I think suits the 56T compressor . I was also thinking of doing that just to shut the sonic shriek up you get from the comp housings slot .

I think Geoff Raicer once quoted those GT32 TS turbine housings as good for up near 500 Hp , long TS thread over at FreshAlloy.com I think .

Their limitation is the 0.78 A/R and the limited realestate in the "T3" flange to fit two inlets .

Its not a perfect solution using single scroll housings on RB engines , its just that with 2.5/2.6/3.0 liters theres more torque to cover the off boost low rev stuff . People seem to find that a well modded head with mild cams and sometimes a sligghtly increased CR lets them err slightly larger on turbine housing A/R , so they ultimately lose little if anything down low and make more power on boost through lower exhaust manifold pressuse vs boost air pressure .

A .

[GTScotT]

I don't have my big can actuator yet, but I do have an AVC-R - if you have any tests you would like me to do which show rpm/speed/boost level I can try and get someone along for a blat with me and film the screen doing whatever pulls you would like to give a rough idea?

Thats an awesome idea mate, really appriciate the offer.

Basically what im most concerned about is my corner exit speed. generally speaking on a twisty run with a sign post of 45 ill be sitting somewhere over 100 where i will then feed the power on in 4th gear for a blinding exit. in the evo if i used the engines rotating momentum to my advantage, with rather ginger throttle i could take the entier 45 bend at close to 150 at top rpm in 3rd. Alternatively I would use 4ths epic torque to pull me through from a slightly lower speed (too unstable at 150 in 4th) and pull me out to a similar speed. for reference the my evo was a IV with a TBE, no other mods, torque was so good that I would not need to downshift to pullaway from a friends 200+rwkw sr20det S13 on a rolling start. 3rd gear at 50 for me and him in 2nd, no chance. 70km for me id be in 4th him in 2nd or 3rd still no good... really need to get that torque back and not defy the point of having a 6cyl with small final outputs.

This could be an interesting thing for all to witness, there are 3 main pulls id want to see if possible. firstly a low speed (20 or 30kmh) flat stick pull in 2nd. Secondly a 50kmh pull in 3rd, squeeze the lemon with the throttle and come on gradually, just to see how it comes on boost, and finally a similar run in 4th gear yet of a higher speed, say 80kmh and a firm yet not WOT squeeze.

Hopefully this sort of evidence will help everyone in deciding if this turbo is for them

And also if you could post up a quick run down of your cars mods yet with exact turbo specs (only if thats not asking too much ofcoarse hehe)

Thanks,

JD

[discopotato03]

I don't think its going to be easy comparing a Skyline like say an R33GTS25T to an Evolution Lancer , even an early one .

They were really aimed at different purposes and buyers .

Correct me if I'm wrong but I think those 4G63 turbo engines were a development in progress and aimed at homologation for rallying . Dirt cars need to have good torque characteristics and the turbo restrictors used to put a very real rev ceiling on that class of car/engine . It forced the manufacturers to make torquey engines with short rev ranges , ALS was something that helped though not really a practical road car thing . Twin scrolled turbos and split pulse exhaust manifolds is probably the easiest way to achieve it .

I think you'll find that all sorts of things like Evo diff ratios and close ratio gearsets make them fairly fiesty for a "production" car .

The Skyline on the other hand is more road car based and easier to live with than the ostentatious Mitsy for normal use .

Your probably going to find that the inline sixes don't feel as strong initially but they will pull tallish gearing easily at low revs .

One of my mentors said that for rally/dirt use AWD was the answer for turbo torque and the Lancers don't seem to be lacking it . Gorilla torque in a RWD car isn't quite the same and while it may be a bit tail out exciting is only using half its tyre contact patches and maybe 45+ % of its weight for traction .

Turbo wise I'm not sure about the GT3076Rs if you want a Lancer type rev and power range , maybe borderline with HKS's GT2835 Pro S . It's really hard to get twin scroll turbo performance from single scroll systems .

A .

[GTScotT]

I totally know where your coming from.. its what is eating at me. Yet you shouldnt underestimate the evos rev range, power came on strong before 3000 and wouldnt hesitate to rev to 8. Mine in the the trim as described had roughly 180 all wheel kw @ 5000rpm... its a crying shame.

Only thing with the 2835 pro S is, id have to buy it in a Garrett equivalent and dont quite have the faith it will pull the numbers.... as idiotic as it is, i will be disappointed if it rolls out any less than 270rwkw.. it is the target number I have set... which is idiotic of me as im a chronic preacher of driver over dyno...

Yet that faces me with the question.. will a 3071 be all that jazz in midrange and torque over the 3076 in an evo kind of way or is it going to come into the issue you have mentioned above, where I wont be able to put the power to the ground regardless and am better off having something that winds up with the revs rather than all at once.

as per usual, I am at a loss.

[TiTAN]

my car has over 300kw @ the wheels and having been in an EVO with ~200kw up to about 100-120km/h both feel similarly quick. its only after you hit 3rd in the skyline that it stretches its legs and walks away.