Need A Solid Opinion: Hks Gtrs Vs 3037 Vs 2835?

[Kaido_RR]

I see. I've already got a non stock dump pipe - I've got 3" from the turbo back, it's just my cat being replaced soon to a high flow unit. Does this mean I can't use the hks dump pipe if you say it fits with 3.5" ? Different size....

When you say "KICK" do you mean it steps out a lot, or you mean more like 'bang for buck'? (Can continue this in PM land if you like). I'm after reasonably smooth power delivery.

Interestingly, RMS just gave me an amazing quote for the GT2835 ProS kit (only a few hundred over the best "landed" price from an O/S vendor), but also said this is the only kit for the R33 GTST "at the moment". I assume that meants only "available" right now, cos nengun has 3037 kits and GTRS kits listed.

is your dump and front pipe in one piece or 2 separated ? if they are separated you shouldn't have an issue fitting up with the hks dump pipe. also the hks kit does not come with a dump to turbo gasket, don't try to make one or put gasket glue on it as hks state the hks gt2835 pros kit for rb25det DOESNOT need a gasket, ive been running my turbo now with no gasket for about 1 year + and no leaking

by kick i mean it puts me back in my seat power is smooth but is nice and hard in 1st gear, i find it jumps onto boost very quick and before you can blink your smashing the limiter.

[sl33py]

If you mean is it twin, no, it's just one thick pipe. If you mean is it in sections... dunno.

If the installation manual says that, my mechanic can read it, and should be fine

Cool @ kick, sounds good to me

[RPR33]

this has been a very good read and made me also want a gt2835? cheers guys

[discopotato03]

I think its very easy to run around in ever decreasing circles trying to nut this one out . I can throw my opinion in but the question you should be asking yourselves is "what do I want this car to do " .

HKS basically caters for three distinct levels of power - actually I should really say three states of tune .

For the : I'm impatient and I want spin the wheels everywhere so need boost from cranking revs - GT-RS .

For the : I want to be able to drive this thing normally , have more squirt and overall usable power - GT2835 OPro S .

For the : I want lotsa grunt and don't care if it comes on hard at 3500 + - GT3076R/GT3037 Pro S .

I know everyones gonna say BS my 3076R/3037 makes pressure under 3000 revs (RB25) but a lot of people say I don't want to "idle" it around everywhere at 3000 rpm just to get a push in the back when I want it . Honestly I can only recall once hearing anyone say that a 3076/3037 came on too soon and that one had the tidliest exhaust housing HKS do (0.61 A/R) so its not surprising . The HKS housing everyone loves on 4 cylinders (for a 3037) is their 0.73 A/R one but I don't think they ever made them in T3 flange . Bad planning really .

What pay and what you get :

A GT-RS is designed to be a basic bolt on easy upgrade for a bit more squirt without the Japanese telephone number mechanics bill . It fits the std manifold/dump and just needs plumbing basics .

Gotta run more later , cheers A .

Edited December 14, 2007 by discopotato03

[joeyjoejoejuniorshabadoo]

This has been my boat for a while now too and i'm pretty sure i'm gonna go the 2835 pro s kit.

after 15 mins on the phone to racepace my understanding is that my car can make the daily driven 250-270 goal on a much safer tune with the pro s over the gtrs due to slightly lower boost being required. (inc cams)

the word safe is enough to sell me as i've spent a fortune on this car as it is and the extra few hundred is but a drop in the ocean when compared to the 20k thats been dropped

Edited December 12, 2007 by joeyjoejoejuniorshabadoo

[discopotato03]

A GT2835 Pro S is also available as bolt on kit but ups the anti to a much better turbine/turbine housing/dump pipe than any bolt on GT28XX system uses . This is where the price hike comes in mainly because their turbine housing outlet is totally unique for a GT30 turbo and needs a unique style of dump pipe . Their system is as good as it gets for a single scroll GT30 IW turbo IMO . You could possibly do a little bit of smoothing at the dump pipes turbo end flange but its a long way ahead of Garretts GT30/35 OEM Ford based IW housings in std form .

I think if people intended to upgrade computer/fueling/intercooling/exhaust systems this would be an appropriate bolt on model specific turbo kit . If all combined properly you could have lots of fun with this one one a daily basis and not have to use high revs all the time .

A GT3037 is getting a bit more serious on an RB25 and its getting into the grey area of losing that nice lower end torque .

They use a larger family of compressor than the 2835 and the turbine is the full sized 60 x 55mm GT30 in 84 trim .

This is what it takes to pump 300+ Kw's worth of air into an RB25 so if thats the ask this one can do it .

If turbine lag concern's you then there are limited ways to tone it down a little but that begins to defeat the purpose of having a turbo of this ones capacity . I haven't had any feedback on how a GT3037 Pro S in 0.68 A/R performs so I don't know how comparable it would be to a Garrett marketed GT3076R IW in 0.63 A/R .

So thats about the size of it , small/med/large . Small being the mild inexpensive (for HKS) upgrade . Medium I think the best broad ranging user friendly (and more expensive) option . Large - for those that are prepared to compromise the user friendly every day performance for more mid range to top end . Its not one I'd use for a mostly suburban car - in Sydney anyway .

Cheers .

[ZenF1]

Hi guys,

Sorry to hi-jack the thread, but I too have been thinking of getting something like the HKS GT-RS or 2835 ProS...for more response, 99% driven on the streets!

Mods on my car currently:

Stock internals

GT35/40

Injectors

Fuel Regulator

External wastegate

High mount manifolds

Front mount

Z32

Turbosmart EBC

Apexi PFC

Custom plenum

As you can see it pretty much has all the bells and whistles, I am pretty sure the Gt35/40 has a T3 flange? Would the GT-RS be a direct take off current turbo and fit directly onto the manifold??? Do I even need the kit? or can I just get the turbo and nothing else, as everything should be already there?

Sorry for the newb questions! lol Thanks

[Lithium]

I am just curious - why do people consider the GT3076R too small for an RB26 but too big for an RB25?

[joeyjoejoejuniorshabadoo]

As a general rule 26's run 2 turbo's not 1

[HKS-R33]

Have you ever thought about a gt35R? Im running a gt35r with a .63 exhaust housing so it spools up a bit faster and i find that its a great combo on an rb25. it comes on boost around 3000rpm and you should see around 280rwkw on about 17 - 18 psi boost. all i need now is some cams to bring boost on a little earlier and the car is perfect for street or track etc

[wolverine]

Hi guys,

Sorry to hi-jack the thread, but I too have been thinking of getting something like the HKS GT-RS or 2835 ProS...for more response, 99% driven on the streets!

Mods on my car currently:

Stock internals

GT35/40

Injectors

Fuel Regulator

External wastegate

High mount manifolds

Front mount

Z32

Turbosmart EBC

Apexi PFC

Custom plenum

As you can see it pretty much has all the bells and whistles, I am pretty sure the Gt35/40 has a T3 flange? Would the GT-RS be a direct take off current turbo and fit directly onto the manifold??? Do I even need the kit? or can I just get the turbo and nothing else, as everything should be already there?

Sorry for the newb questions! lol Thanks

HKS GT-RS bolts up to the standard factory gear and comes in a kit form with all the lines and gaskets required to bolt on to the factory exh manifold.

the HKS2835ProS comes as either a turbo or in kit form (and therefore straight bolt-on to factory exh manifold) with its own lines and dump pipe (ie diff flange to standard). the dump is a short split number that replaces the factory dump and bolts onto the standard location front pipe.

Edited December 15, 2007 by wolverine

[discopotato03]

Lithium I think you'll find that people with RB26's just accept the fact that in the early factory state of tune theres not a lot of poke low down anyway so what they don't have they don't miss .

Its probably no issue to make a GT3582R "spool up" in the mid upper 3000s rev range so they most likely go for a turbo that can make serious power starting somewhere about where the std twins do .

I really don't see a problem using a GT3076R on an RB26 - other than you lose the twin turbine housings (twin nozzles) and split exhaust system . Very OT but by the time you fork out for another manifold/gate/dump/lines you may have spent enough to buy direct fit turbos like GT-SS's or the Garrett equivalent .

RB25's are definately in a lower state of tune than RB26's and thats because they are the toned down less expensive to manufacture ROAD car edition . Nissan obviously wanted the sort of power delivery characteristics that most people could live with on a daily basis in suburbia . The obvious internal differences are the higher static compression ratio and the single throttle plenum style inlet manifold which would be easier to manage than the multiple ones because they can pass a lot of air even when only just open . The VCT must do positive things as well . Putting around with an RB25 probably gives better MPG and thats not insignificant to some people .

Possibly not as OT but if you ever looked at twin HKS spec 2835's and 3037's on RB26's the compressor trims tend to drop from 56 to 52 because they are struggling to get them going to start with . Extreme drag set ups and personally I reckon you'd have rocks in your head to do such a thing to a road registered car . HKS could and SHOULD have offered smaller comp trim options in both Pro S turbos - I'd say the max power potential numbers got in the way and looked limp in the hero stakes . If turbos were marketed around torque delivery rather than PS or Kw I think the situation would be different .

Cheers A .

[sl33py]

Haha haven't looked at this thread in a while... my stock turbo actually died the other day (randomly, under light load doing 70kph on the way home from work) so now I'm forced to make the choice!

I just ordered a GTRS kit. I hate lag, the car is too laggy in stock form IMO, and my mechanic said the 2835 will feel laggier whereas the GTRS will be similar or better depending on other things. I WAS going to get the 2835 after this thread and other investigation but my mechanic/tuner said less 2835 kits have been sold recently and apparently they are out of favour. He knew I was buying the turbo elsewhere, so it's not like he was just trying to flog off stock either. Anyway money's tight atm, so I only needed a very light push in the direction of the cheaper GTRS. I think I'll be happy with 250-260rwkw, which my mechanic says will be achievable and safe (he's got 240rwkw from a 2530 previously). Will be interesting to see how it turns out after all my research! Basically what most ppl were saying was "you'll be happy with both" Can't wait to get it put in early next year

Edited December 17, 2007 by sl33py

[Pattygtst]

$2260.03 from nengun +delivery http://www.nengun.com/hks/turbo-kit-gt-rs

Or local sliding performance $2900

I heard nengun is slow with delivery, and sliding performance maybe too

[Roy]

Ok, my opinion.

Go the 3037. Go the internal gate option and i think its best for your application for the following reasons.

To make the power you want it will require less boost. The RB25 has a higher compression ratio then other RBs and it has the weakest pistons of the RB engines. So boost is the one thing you want to try and keep under control.

The 2835 will be more responsive, but will require more boost. It will also put more wear on the engine as in your day to day driving the turbo will more often run through its peak torque rpm with your foot up it and under boost. Not a big deal, but the less reponsive 3037 will not be boosting as often on the street, and the mid range torque hit will be harsher with the 2835 with the boost you will be running to make the power you want. Its just more load on the engine.

For those that say 250rwkws is really the safe limit?!?!? I disagree. A badly tuned 200rwkws is more likely to go bang then a well tuned and supported 280rwkws. Only nothing is safe when you start ripping off the stuff that Nissan has done the R&D on. In my eyes there is nothing safer about 250rwkws then 280rwks on a std RB25, the general engineering of the engine is there for it to be reliable. My vote it will be more reliable with the 3037 making 280rwkws then the 2835 making 270-280rwkws

[Dale FZ1]

FWIW, I have driven a friend's 2835 0.68 Pro S equipped RB25 (265kW) vs my 3037 0.87 Pro S (270kW) back to back and side by side. There is a discernable difference in delivery, but the mid range torque of the 3037 does not "hit", nor is it "harsh". It is just different, and both our opinions were that it felt better than the 2835.

The 2835 was slightly (and very slightly at that) more torque productive @ 2500rpm when loaded in a high gear on a steep uphill pinch, but that was about it. Nice turbo, but felt much tamer by comparison. You could see the boost needle moving faster, earlier, but the car did not seem to respond quite the same. I think it comes back to the concept of "boost being a measure of resistance to airflow".

[discopotato03]

Had the turbine housing A/R ratios both been 0.87 I reckon it would have been a more even test .

A .

[Roy]

What boost are each setups running and are they tuned by the same mechanic?

[Dale FZ1]

Had the turbine housing A/R ratios both been 0.87 I reckon it would have been a more even test .

It seems that the 2835 + 0.68A/R and 3037 + 0.87A/R are the IW housing specs most often cited as chosen for fitment to RB25 for various reasons. BTW, the HKS 2835 Pro S uses the 56.5mm rotor, so suggesting the turbine combinations would be evened up by running the same housing A/R is a null argument. The power outputs in the noise-legal specs of these cars is not overly different, and the dyno sheets show likewise. Glen is running Pon Cams and has less noise output. The mechanical specs are not identical, but an example of similar achievements via different routes. We were both of the opinion that it was an even comparison. He has a 0.87 housing spare, but that was not fitted. If it was, and his top end breathing was opened up further then I possibly could remove my tailpipe baffle and release 20kW to keep it an even test. Swings and roundabouts.

The point was, there can be similar overall results achieved by both units. But the on-road difference is noticeable. Neither will frighten you with savage wheelspin and a vertical wall of torque gain as they come on boost. Both are extremely driveable, and support progressive delivery of a large amount of power from an RB25.

[Dale FZ1]

What boost are each setups running and are they tuned by the same mechanic?

The 3037 runs 17.3psi max with baffled exhaust, and the 2835 runs somewhere just over 18psi.

Full load air/fuel above 4000 is leaner for the 3037, at ~ 12.0 vs ~11.7:1. Ignition mapping was compared and is broadly very similar. Total full load timing for each is around 34 degrees. Different tuners, but with FCEdit we can easily compare all aspects of the tunes and log to compare the results of what happens on road. There is more to be had from either setup, but the approach to tuning is quite similar.