Hks2835 Tune

[joeyjoejoejuniorshabadoo]

how close is this dynopack to the dynodyanmic?

that's the same result as a DD

dynapack has a correction mode that gives results to within a few kw (which my car has backed up on a few dyno's)

[89CAL]

for those who wanted to see the GT2835 KAI

From the specs I've seen, its near identical to the Pro S. Like I said I'm pretty sure most of the difference is in the internal design. Specs show slightly more power and slightly less torque but I've seen conflicting specs on power and torque so not 100% sure till it goes on the car or I can find someone else who has tested one

[75coupe]

it has a different exhaust housing, port shapes and different exhaust flange, as well as the slotted comp inlet...

does the kit come with a HKS dump and is it a split dump design?

[75coupe]

that is the Pro S exhaust housing off a 2835 GT Pro S I have for sale currently

[89CAL]

ahh i see

now a few things make sense

yeah it has the Nissan 5 flange for direct bolt up to dump pipe. No HKS Dump provided as there is with the Pro S kit

[75coupe]

oh wow, how good would that be, a direct bolt on turbo then eh, able to make 290rwkw with awesome response... thats cool...

now do the std oil and water bolt up as well...

[89CAL]

dont believe so... braided oil and water lines came in the kit so I can only guess there included because stock items dont fit. But thats only an assumption, they will be going on anyway lol

BTW: I didnt relise the Pro S didnt bolt straight up to the dump pipe.... This saves me a bunch of headaches trying to get my dump pipe changed to fit between the HKS dump and the Cat

Edited December 2, 2010 by 89CAL

[75coupe]

well the hks dump replaces the std dump, to fit the front pipe...

thats all pretty cool though, it looks like the slotted front inlet could replaced with the std ProS one and vice versa, I wonder what the slots would do in comparison to the ProS one...

[89CAL]

There supposed to be anti-surge slots I'm pretty sure. The HKS T04's (?) have them

As for their purpose, Im guessing they help with surging at high RPM/Boost but wether I'm right and how it would do that is beyond me....

Someone should be able to shed some light on that

And the dilema I was talking about with the dump was: Because I have a 3 Inch bellmouth dump pipe that goes from turbo to Cat. I would need to modify that or buy a new front pipe to fit from the HKS dump to the Cat.

I had assumed that the rear would bolt up to the standard pattern but I sorta relise now where I went wrong lol. Either way, KAI seems good for me

[joeyjoejoejuniorshabadoo]

from nengun

11004-AN001

Nissan - Skyline - ECR33/ER34 - GT2835 Pro S - A/R 0.68

Skyline - R33 GTS-t S2 - ECR33

Skyline - R33 GTS-t S1 - ECR33

Skyline - R34 GTT - ER34 DISCONTINUED

ba-bow!

[89CAL]

I ordered the Pro S from NENGUN and a little while after that I got an email saying that the Pro S was proving difficult to get but a new version was available - GT2835 KAI

But for the life of me I Cant find the KAI on the Nengun site?

[JonnoHR31]

There supposed to be anti-surge slots I'm pretty sure. The HKS T04's (?) have them

As for their purpose, Im guessing they help with surging at high RPM/Boost but wether I'm right and how it would do that is beyond me....

Someone should be able to shed some light on that

yer they're anti surge slots. basicaly surge is when the turbo is pumping more air than the engine can swallow, this air then makes it way back through the turbo whilst its still trying to pump air fowards, can get pretty nasty. the slots basically recirculate the air around the comp wheel to stop this.

surge usually occurs when you have a smallish exhaust housing on a high flowing compressor, the small housing gets the turbo spinning very fast early in the rev range and therefore it starts pumping a lot of air, the engine isnt revving high enough to be able to swallow this much air and you get surge. how this excess air doesnt create massive amounts of boost is beyond me but theres some fluid dynamics reason for it.

and for the record, standard rb20/25 dump pattern is 6 bolt not 5

[discopotato03]

Yes I picked up on the turbine housing as well , can the owner of the GT2835KAI please check inside the mounting flanges inlet for a cast in A/R number .

I hope I'm wrong but I suspect HKS may have bored out the T3 flanged 0.64 A/R GT28 turbine housing they use on RB spec 2530 GTSS and GTRS turbos . This would be a much cheaper option than supplying the unique GT Pro S turbine housing with its equally unique dump pipe .

Will look into this , cheers A .

[Rolls]

yer they're anti surge slots. basicaly surge is when the turbo is pumping more air than the engine can swallow, this air then makes it way back through the turbo whilst its still trying to pump air fowards, can get pretty nasty. the slots basically recirculate the air around the comp wheel to stop this.

what stops the surge slots from recirculating at high revs and essentially wasting the compressors flow? I never understood this, I figured if they leaked at low revs to stop surge, why wouldn't they leak at high revs?

I figured it would be easier to spit the air out the slots to a vacuum (the intake) than into the engine which is under pressure hence they would leak all the time.

is it something to do with the higher the velocity of the compressor the harder it is for air to get out the holes?

Edited December 2, 2010 by Rolls

[89CAL]

Cant see anything inside the flange inlet but it has 064 stamped around the back adjacent to where the HKS logo is, Kinda sounds a bit like it

[joeyjoejoejuniorshabadoo]

Yes I picked up on the turbine housing as well , can the owner of the GT2835KAI please check inside the mounting flanges inlet for a cast in A/R number .

I hope I'm wrong but I suspect HKS may have bored out the T3 flanged 0.64 A/R GT28 turbine housing they use on RB spec 2530 GTSS and GTRS turbos . This would be a much cheaper option than supplying the unique GT Pro S turbine housing with its equally unique dump pipe .

Will look into this , cheers A .

as far as i know this is what the 2835 kai is

it is not a new turbo and was available on nengun when i bought my pro s over 2 years ago

i remember researching it at the time and finding that it was a slightly lesser unit than the pro s and dismissing it as an option

it was also cheaper

[discopotato03]

what stops the surge slots from recirculating at high revs and essentially wasting the compressors flow? I never understood this, I figured if they leaked at low revs to stop surge, why wouldn't they leak at high revs?

I figured it would be easier to spit the air out the slots to a vacuum (the intake) than into the engine which is under pressure hence they would leak all the time.

is it something to do with the higher the velocity of the compressor the harder it is for air to get out the holes?

No its more of a pressure balance thing . What happens is the leading edges of the lower or splitter blades are just inside or below where the radial slot is located . When the pressure is higher in front of the splitter blades the full height blades bypass some air out through the slot purely because its the lower pressure or least path of resistance . At higher revs the engine can swallow more air so the pressure in front of the splitter blades decreases so the air previously being bypassed goes through the housing to the engine .

The whole idea of port shrouded comp housings is to allow a larger compressor wheel or wheel trim to be used while avoiding compressor surge .

The other thing is that it allows smaller A/R turbine housings so be used on biggish turbos and avoid compressor surge issues .

A good example of a turbo most know of is the Garrett/HKS GT3076R/GT3037 56 trim . Turbine housings from HKS alone start a 0.61 A/R and go up to from memory 1.12 and Garrett's range from 0.63 to 1.06 A/R . I reckon you'd have a hard time avoiding surge with the 0.61 or the 0.63 housings given that the compressor is good for 500+ horsepower , people who've use both those housing never mention comp surge so the PS'd housings do work .

A .

[JonnoHR31]

knew you'd have the answers.

any idea why surge doesnt show up as excessive boost? or does it, but the gate cant react fast enough to control it?

Edited December 2, 2010 by JonnoHR31

[GTScotT]

Dang, I think disco is correct in that case.. Seems to be a re profiled GTRS housing. Am now keen to see the results compared to the old 2835... perhaps this is what necessitated the surge slots.. Restrict outright housing flow in order to achieve even more midrange and alleviate the issue of surge by means of compressor cover..

Le hmm.

75coupe is that your 2835 on egay?

[75coupe]

75coupe is that your 2835 on egay?

nope not its my spare used 2835 on ebay... it is listed in the SAU for sale section though...

no damage its ready to be used, just that I found a brand new one amazingly cheap and couldnt resist.