Hks Gt2835Kai Still A Good Option?

[Torques]

Hi,

Is the GT2835Kai still a good option these days or has it been super-seeded by newer designs?

What power output is reasonable to expect with that turbo?

I currently have a non ball bearing hybrid making 260KW at the wheels.

(on RB25)

So I am remotely thinking about an upgrade to get me into the 300KW region.

Would that be realistic with the GT2835Kai?

Thanks ..

[Simon-S14]

No. Just get the 3076 like everyone else does on the tried and tested path to 300rwkw

[LaurelPWR]

You will achieve your 300wkw figure with a 2835kai + E85 easily ... Obviously with appropriate supporting mods...

[scotty nm35]

I think a GTX28 would be a better option... And cheaper.

[89CAL]

I have a second hand gt2835kai if you decide you want one.

[LaurelPWR]

I have a second hand gt2835kai if you decide you want one.

How much and what condition? Lol

[89CAL]

I have a for sale thread somewhere. Chasing $1000 for it, comes with everything from the kit minus the gaskets. Think its in the queensland classifieds. Should be near the top

[discopotato03]

A GT2835 KAI would be good if you can find a 2835 Pro S turbine housing for it .

In T3 flange and IW from Garrett their GTX3067R is rated at 500 crank horsepower , no ones tried one AFAIK on an RB25 yet and is possibly similar power wise to a GT2835 Pro S 0.68 AR .

GT3076Rs are tried and proven 300+ RWKW if the engine and exhaust is up to it .

A .

[Torques]

Thanks for the feedback.

The easiest option for me is a drop in replacement since this is what I have right now.

So I wanted to know if the KAI would get me towards 300KW.

Going E85 is not really an option since the car is used as daily ride and E85 is not that common in the UK.

Of course I could throw in a bigger turbo on hi/low mount and make 300KW.

But that would constitute ripping my current set-up apart.

Yes, my car is set-up for 300KW (4 Inch / 3.5, Poncams, TomeiFuel Pump, 555 Injectors, Blitz FMIC etc.)

I am making the current 260KW at .9 BAR ! so the engine flows very well.

[89CAL]

This is my turbo for sale if your interested anyway. For Sale thread

[Chris32]

If your making 260kw @ less than 14psi, I'd be winding your existing turbo up to 20-22psi and seeing how close you get.

You'll need to run this sort of boost to crack 300 if you swapped out your turbo for those mentioned anyway looking at various results from others running 300+

[Torques]

If your making 260kw @ less than 14psi, I'd be winding your existing turbo up to 20-22psi and seeing how close you get.

You'll need to run this sort of boost to crack 300 if you swapped out your turbo for those mentioned anyway looking at various results from others running 300+

Yes, but the engine outflows the hybrid-turbo so I can not up the boost.

In other terms:

The turbo can not deliver more flow and is running out of puff.

That's why I am looking into other turbo options.

[scotty nm35]

Because the wastegate is blowing open from manifold pressure? Or have you tied the wastegate shut and can't get it to hold more?

[Torques]

I never investigated the wastegate but the actuator is set to one bar and the controller .5 bar higher.

The turbo is rated at around 400HP (based on what it can flow) and boost drops gradually since the turbo can not keep up with air demand from the engine.

You can see this on many dyno graphs that boost gradually drops and this is not due to the wastegate.

(though a blown open gate is always an option)

Boost is meaningless anyhow, it is the mass of air going into the engine which makes power (+ the fuel of course)

Still I will check on the WG but I think that is not the problem, I just need a bigger turbo

[scotty nm35]

Believe me, if you can get a stronger spring on the gate the manifold will hold more pressure, meaning the turbo will spin faster and create more boost. This will usually make more power and always add torque.

More preload on the actuator doesn't work as well as a properly selected gate spring. Try and run as close to your desired boost as possible.

A bigger turbo comes with drawbacks. Not saying don't do it, but there are many ways to get more power without changing it.

[KiwiRS4T]

Yes, but the engine outflows the hybrid-turbo so I can not up the boost.

In other terms:

The turbo can not deliver more flow and is running out of puff.

That's why I am looking into other turbo options.

If you can keep your wastegate closed longer you may make more boost. You say you need airflow not boost but to use your terminology when your boost gauge reads 20 psi that indicates that the turbo has caught up to the flow through the engine - you have no other way of measuring flow unless you have a read out from the maf.

Having said that it is possible that your turbo has indeed run out of puff but check the wastegate boost control first.

[Torques]

If you can keep your wastegate closed longer you may make more boost. You say you need airflow not boost but to use your terminology when your boost gauge reads 20 psi that indicates that the turbo has caught up to the flow through the engine - you have no other way of measuring flow unless you have a read out from the maf.

Having said that it is possible that your turbo has indeed run out of puff but check the wastegate boost control first.

HI!

Misunderstanding:

I did not say I need more airflow not boost, but merely said that it's not boost which makes the power. (since people always say you need such and such boost levels for such and such power)

And of course If my boost goes up the airflow will increase.

I will check the actuator but it is an adjustable one and the preload (of the spring) is pretty heavy.

Btw:

I can read my MAF values (voltage) in real time through Nistune.

This is a direct representation of mass air flow (MAF)

Cheers

[Torques]

Believe me, if you can get a stronger spring on the gate the manifold will hold more pressure, meaning the turbo will spin faster and create more boost. This will usually make more power and always add torque.

More preload on the actuator doesn't work as well as a properly selected gate spring. Try and run as close to your desired boost as possible.

A bigger turbo comes with drawbacks. Not saying don't do it, but there are many ways to get more power without changing it.

Thanks,

Yes, I don't want any more lag that's why I was investigating the ball bearing HKS.

At current I like my setup / engine response and worked long and hard to achieve this.

260KW at the wheels is not bad and the car is fun to drive.

I will check on the actuator just to be 100% certain.

But as said the Turbo is rated at 400HP and I think I simply reached that limit.

[LaurelPWR]

My hks gtrs is rated at 400bhp but it made 407whp (with E85) made 365whp on bp98 on 18psi so if your making 260wkw on 14psi wind boost up a bit and you'll get closer to your goal for sure dude...

[Dale FZ1]

I think Simon's suggestion at post #2 made the most sense given the OP is in the UK and not running E85.

Looking at this thread, if the OP's setup consists of bolt-on airflow modifications only (inlet pipes, turbo, FMIC, poncams and exhaust), I'd suggest his dyno might be happier than the typical Australian spec. 260rwkW from 13psi on an RB25 is not something generally seen.