Vg30 Gcg Hi Flow Or Gtrs On Mild Modded Gts25t ?

[discopotato03]

Mods first then comparison .

96 S2 GTS25T with R34 SMIC/PFC/Z32/740 Nismos/ported head/Poncams/os exhaust valves/9.2-3 CR . Nismo catback .

I need a direct comparison of the larger OP6/VG30 turbine housing sized GCG BB Hi Flow vs HKS's GTRS kit turbo for R33 .

I have searched and my ask is this .

Dyno numbers don't keep me awake at night and the butt dyno/smile generator when no one else's around ometer is king .

Basically which will give best all round street performance meaning easy to drive sedately and angry when the metal meets the pedal .

Probably a hard question to answer but maybe someone here has tried both and can pass on the real world differences - in an R33 coupe .

I am taking into account how the Hi Flow looks factory and need to know if the RB GTRS is better enough to look almost factory . Has anyone been bitten for having A GTRS ? I've never ever been pulled over or asked for a look at anything though my Skyline doesn't do many miles .

So help this middle aged old fella choose , cheers A .

[zebra]

My vote would be to go HKS, however i have not had either turbo,

but from what I have seen and heard the GT-RS is more progressive through the midrange where the Hi-flow is a little on on off.

Having said that I have no doubt either would bring a smile to your dial.

[PM-R33]

I can only speak on a GT-RS and stock turbo since that is all that I have had on my car.

Personally I love the GT-RS and could not praise it enough.

[kwickr33]

Those are the best results from Status dyno so might be more accountable in some sense.

R34 GTRS HKS

Red line is 98, Green line is E85

GCG OP6 High flow

Hypergear's OP6 high flow

Edited October 28, 2010 by kwickr33

[PM-R33]

Ummm your dyno graphs are way off.

The first one is Hamish's HKS 2835 on a R33 not a HKS GT-RS on a R34.

The second one is ment to be part of the last one; Hypergear.

[kwickr33]

The first one is Hamish's HKS 2835 on a R33 not a HKS GT-RS on a R34.

The second one is ment to be part of the last one; Hypergear.

Aren't the HKS 2835 ProS is the turbo that comes with the HKS GTRS Kit for GTT?

[discopotato03]

No , a HKS GT2835 Pros is HKSish for a cropped turbine GT3071R 56T - and in HKS's custom single turbo RB type GT30 IW housings .

A .

[zebra]

Aren't the HKS 2835 ProS is the turbo that comes with the HKS GTRS Kit for GTT?

FKN LOL!!!

Why would a HKS GT2835 Pro S come in a GT-RS kit?

Sorry for whoring your thread Disco, but that has made my day hahaha

[chiksluvit]

I've got a VG30 hiflow from GCG, it kicks real hard at 4000rpm when it gets full 16psi, boost build up isn't too bad before that but not as responsive/ linear as GTRS or R33 highflow.

GCG's advised that the OP6 hiflow is good for top end, and the rb25 power thread suggests that people are pulling about 270rwkw with it. not sure what GTRS is rated but I'm guessing that the OP6 will pull bigger number while GTRS is a better option for better response

[paulr33]

if money is unlimited

HKS GT-RS

if you want more top end and a bit more lag, VG30 rear

if you want flat out response and good range of power GTS25T rear

but you mentioned R34 SMIC

this will kill any turbocharger you choose

heat soak city

[chiksluvit]

also

the high flowed OP6 will also make your exhaust a lot louder...

[STATUS]

if money is unlimited

HKS GT-RS

if you want more top end and a bit more lag, VG30 rear

if you want flat out response and good range of power GTS25T rear

but you mentioned R34 SMIC

this will kill any turbocharger you choose

heat soak city

yep im glad paul picked up on this as i was about to type GTRS... now i reckon nothing as the r34 smic is useless with anything bigger than stock... even running 14 psi on the std turbo they heat soak so quickly its not funny (14 to 16psi only on some guys who wanted a KW figure usually we run no more than 12-13)

Even the ARC smic are useless, we logged a S15 @ winton and it made 1 lap before the ait started pulling lots of timing. Put a turn flow ARC on it and it never pulled any.

[R31Nismoid]

totally ageee Paul. the R34 SMIC is a major issue.

By 220rwkw that's basically the limit.

They are too restrictive for anything other than factory turbo airflow.

Honestly if you don't change that, then any turbo chosen, overall setup will suffer.

I've not had the pleasure of a GT-RS equipped experience but the GCG OP6, i have.

Boost and delivery was very linear. The car didn't feel 'fast' due to this, but the speedo dismissed that... it's delivery was that good it was deceptive.

although i doubt i need to say this - ensure you get the heavy duty actuator

[andymoocow]

i've had a GCG R33 highflow (with standard rear housing) and it was a cracker of a turbo for the budget conscious. I now have a GT-RS turbo.

THE GCG was a great turbo, sensational bang for buck for about $1K second hand. Compared to the GT-RS i found the GCG gave a bigger "whack in the seat" factor when it hit full boost, the GT-RS is much more responsive and smooth in its delivery. Its been a long time since i've driven a stock turbo car, but the GT-RS spools so smoothly and quickly, its hard to fault it. THe GT-RS is much smoother and I found it very street friendly. I live in suburbia with mostly 50km/hr zones, so i need a responsive turbo.

It also comes down to your tune, the boost you're running, etc etc.

My GT-RS is currently making 242rwkw, my tuner said there is plenty more in it, but i am more than happy with the current tune, nice and conservative, yet plenty of power.

Short story, i love my GT-RS turbo, they do cost a fair bit, but once you've got it up and running you'll be more than happy with your investment.

[paulr33]

yeah the GTRS is really the premium turbo option for that power range. no issues with unknown gotchas, mixed up mangled hiflows and poor rebuilds etc as the GTRS is brand new

if you can find a GCG highflow for 1k you are laughing and you would get this no doubt. a GCG brand new is 2k from memory so depending on budget, some may prefer GTRS and sell their old turbo instead. the GTRS will also sound different when spooling up vs normal turbo or GCG hiflow

i reckon the SMIC would cap out at a max of 180rwkw

any more than that and you basically just increase the intake temp for no gains

ie the more boost you dial in and harder you push it, the more hotter the intake temp is which results in less power anyway

the core size and its location hamper anything

[discopotato03]

At least I'm hearing what I expected about the GTRS , my one is not brand spankers but I know its previous owner would have treated it well anyway .

Its the full kit except the dump pipe was fab'd to suit a "Skyline Wagon" ...

The impression everyone gave me was that the GCG Hi Flow was good but never felf really sharp and thats almost certainly because Hi Flows don't have housings designed to match the foreign wheels so compromises creep in . New for new a GCG Hi Flow will always be cheaper than a GTRS kit so bang for buck comes into it . I recon if they were cost neutral there would be more GTRS's around .

When I pick it up I'm going to compare the RS's turbine housing to a cleaned up (bead blasted) perfect std OP6 turbine housing I have here . I've never had a HKS T3 flanged GT28 turbine housing to compare anything with but I'm sort of hoping that the Hitachi one is a little larger because it could be a real interesting addition to a GTRS if it is . I do have my T25 flanged GT2860RS in the cave and its 0.86 A/R GT28 housing would be interesting to compare to the HKS 0.64 one and the HitachI OP6 one . I always though HKS were limp for not making a T3 flanged 0.86 housing though thinking about it the only application would have been RB25's . T3 flanged 2530/2535/GTRS were clearly intended to suit RB20 and 25 and a larger housing I think would have been a bit lazy on RB20's .

My goals have changed in the past couple of years and I'm now more interested in the sort of power that's practical and usable in a road car , the different states "revenue protection squad" backed up in NSW by their way too powerful running dogs (RTA) have made driving the least bit spiritedly a licence burning experience . The sad fact is that trying to use 270+ at the treads is getting hard with a RWD Skyline when even the std CPU fan turbo can smoke 1st gear in the dry .

I did have high ideas earlier about larger turbos and RB30's but now I want something that's small enough and responsive enough to be smooth and torquey with std manifolds . I really need something that can pull a bit from part throttle and an easy 240-250 will be plenty for me . I really don't care if it falls over at 5500-6000 because your licence is gone in 3rd 4th 5th anyway .

With my style of driving 1st doesn't go to far , 2nd is where its and at and the other three are a short shift up to legal cruising speeds . I might drop a cog to overtake or accelerate uphill at times and the power/torque/boost needs to be there from say 2500 revs .

Sorry people but AWD has changed the way I think about getting power to the ground , having engines with linear almost OE like power delivery is the way to go . My Subaru is more old world than old school but seeing the transformation from FrWD to AWD was a real interesting learning curve .

My Evo 6 is mechanically factory and its really punchy in the lower gears , no tramp slip screech jut gone .

The RWD really needs to have fine precise throttle response and I think this GTRS will do it for my tastes .

Yes the intertoaster , I had thought that it would be lacking and again I'll have to find some bang for buck solution that can fit in without cutting anything .

A while back I read a long post here about JJs return flow IC kit and it sounds fair if something good enough and stealthy is needed .

Do we reckon it would be reasonable for a 250 Kw GTS25T ?

Lastly the old Suber Dak Dak is not going to be re-registered (sold or parted out) so the Nissan will become the daily driver and no doubt get more attention paid to it .

A .

Question , is a 96 build GTS25T with a genuine 91K a rare beast nowdays ?

Edited November 1, 2010 by discopotato03

[PM-R33]

I suppose it could be classed as "rareish". Mine is a 96 and has around 105,000km on it and is a lot less that what I see most at.

[GTScotT]

A while back I read a long post here about JJs return flow IC kit and it sounds fair if something good enough and stealthy is needed .

Do we reckon it would be reasonable for a 250 Kw GTS25T ?

Ive got one thats done the better part of 2KM driving now sitting in my garage.

I fitted it and 2 days later got a good offer on my turbo kit, and have since gone a motor that doesnt suit the return flow.

The core quality is excellent, far better than what I remember from JJR coolers not so long ago.

Am in Bankstown if you want to come have a look and offer me a reasonable price (for a basically new unboxed item).

[paulr33]

97 with 230k and std turbo still

[andymoocow]

if you live in Sydney and can make it to the North Sydney area i can happily take you for a spin in my R33 with a GT-RS turbo and you can make your own decision from there on how it pulls and sounds.......