Hi-Flow Turbo (RB25DET)

[Abo Bob]

I have now installed my high flow from GCG however I had some issues with fuel pressure so was unable to turn the boost up much. No dyno readout yet but I can say that at 0.8 bar I noticed the boost comes on later than stock but harder.

The on boost part of the rev range in first gear gets used up dangerously quickly; I short changed by accident several times and hit the rev limiter once which I don't like doing.

I don't know how much power I've got but I overtook an R34 GTR down the Eastern Creek straight yesterday. (Only just)

When I get a hold of a fuel regulator I will turn the boost up and let you all know.

[Sydneykid]

I still think $1,950 is quite a high price for a hi-flow turbo even though it is a straight bolt-on and is the major thing making me look at a HKS/Garret kit.

I have done this calculation a number of times, if you add up;

the price of the turbo itself

the extra parts you have to buy

the stuff that has to be fabricated

the frustration when it doens't fit or something is missing

the amount of time your car is off the road

And then compare it to a swap to a high flow that can be done in a couple of hours, you will find it much cheaper in total. Plus with a GCG ball bearing hi flow there are at least 10 Skylines I know of, and 4 that I have personally been involved with, that make the 450 bhp that the tubo is rated at. That's as close to a guaranteed result as you are going to get. And it looks standard and you will never get EPA busted for that.

My 20 cents worth

[jazza08]

How much at the wheels are they making dude on what sort of boost levels?

I decided it will be the route im taking and want to know what kinda power i cud get outta it in the end...

[Sydneykid]

How much at the wheels are they making dude on what sort of boost levels?

I decided it will be the route im taking and want to know what kinda power i cud get outta it in the end...

450 bhp =336 kw - 60rwkw (losses) = 276 rwkw

The R34GTT makes 265 rwkw at 1.3 bar on our dyno using Optimax and it's not tuned too close to the edge. It gets driven every day in city traffic, rain, hail or shine and it is used on the circuit a few times a year and the drag strip (11.9 at 120 mph) very rarely. I have used Elf Turbo Max in it for a test and it made 291 rwkw with only ignition timing changes.

Ken's R33GTST made 263 rwkw, Adrian's R33GTST made 267 rwkw, Dave's R34GTT made 271 rwkw...........there are a few more.

If you are sticking with the standard internals, I can't think of another turbo that is as good for all round use.

[jazza08]

Ok, i want to know who hi-flows this turbo as they as going to do mine reading those!!

Can you post up or PM me the address or website of the people who do the hi-flowing of the rb25 turbos for me plz! Pretty damn good figures..

[4door_Sleeper]

Ok, i want to know who hi-flows this turbo as they as going to do mine reading those!!

Can you post up or PM me the address or website of the people who do the hi-flowing of the rb25 turbos for me plz! Pretty damn good figures..

Try GCG turbos at www.gcg.com.au - I'm sure they were mentioned earlier in this thread. They also did my turbo and I can vouch for the results Sydney Kid and others mentioned.

IMHO well worth the money.

[jazza08]

Thanks dude

I can see they have alot of happy customers, might ave to save a few more $$ to get them to rebuild it as they probably charge more seeing as they come out with awsome results!

Any idea what to ask them...? Im looking for 300+rwhp from the turbo, dont need much more than that but if it cud stretch abit more that wud be good!

[benm]

The standard "GCG Hi-flow 450hp" will do that. Put aside about $2,200 fitted.

[jazza08]

How about not fitted? As im not over east so they wont fit it just rebuild/hi-flow it!

Will this be fairly laggy as its more powerful??

[benm]

I believe it's about $1,900ish just give them a call on Monday.

[Abo Bob]

They don't fit them themselves anyway.

[stealth]

I have just gone through this very excercise myself:

Car does 220kwatw at the moment with a 400hp rated turbo,

which is max. safe capacity. Have already got fuel regulator, pump, hiflow injectors, intercooler and PFC etc. std manafold. wanted a simple bolt on turbo to get around 400hp so turbo had to be internally gated and rated at min. of 550hp. I use the car predominately for circuit (with the occassional qtr mile run)so needed quick boost with good mid range torque - start boost at 2000 and maxed by 4000 but pwr still climbing to 7000  

Through several performance mechanics (guys who actually run and tune track cars) it came down to 2 choices

1. GT35/40R internally gated rated 700hp

The internally gated GT only comes in exhaust AR1.06 which could lag but would have great legs right up to the rev limit. Has ceramic ball bearings so if backfire could risk breaking the bearing. Otherwise a perfectly matched turbo for RB25DET

2. Std nissan turbo hiflowed rated 500hp

Quite a few shops are high flowing and struggling getting 350hp, so you need to ensure who ever does the high flow is the real deal and will g'tee 550hp. Which means the inlet and out let are widened and much tougher wheels, shaft and th a  bush bearings.  

Although the price for both was very similar and the temptaion was to go the new I went for the hiflow because:

- good track record on some quick GTRs

- smaller exhaust AR which means ON BOOST quicker

- 12mth warranty

- garaunteed bolt on componentry

- matched compressor flow capacity with exhaust so the turbo works at an optimum speed and the lowest temp while maintaining boost

This was my experience up to choosing the turbo. Its actually being installed this weekend and gets tuned in a week so I'll let you know how it goes.

Hope this helps. What I found was the more you ask the more confusing it gets - so get advice from someone who has got the RESULTS. Good luck

So the hi flow has been fitted and tune in Bris

After $400+ spent on tuning I went from a start dyno of 300hp to final dyno of 302hp

And the tuner telling me you wont get more than that out of a hiflow because they are really only 450hp turbo not 550hp as the receipt says

If I had know the figure stated was a bullshit figure I would have gone the 700hp GT, as I effectly have gone from a 380 rated turbo to a 450. Big bucks little gain

Picked up 0.2sec on qtr mile

Lesson - they'll tell you anything to upgrade a turbo

[4door_Sleeper]

So the hi flow has been fitted and tune in Bris

After $400+ spent on tuning I went from a start dyno of 300hp to final dyno of 302hp

And the tuner telling me you wont get  more than that out of a hiflow because they are really only 450hp turbo not 550hp as the receipt says  

If I had know the figure stated was a bullshit figure I would have gone the 700hp GT, as I effectly have gone from a 380 rated turbo to a 450. Big bucks little gain

Picked up 0.2sec on qtr mile

Lesson - they'll tell you anything to upgrade a turbo

Where did you get the turbo from?

This matches some of the stories I was told about by workshops in Adelaide, and the main reason I went to GCG instead of some of the local turbo shops.

You may be able to put in a claim through consumer affairs if they advised a power rating that isnt achievable (and provided your support systems are not the problem)

[jazza08]

thats crap for u dude

Atleast u know the turbo will last you being rebuilt etc.. but not wat u paid for

[stealth]

Where did you get the turbo from?

This matches some of the stories I was told about by workshops in Adelaide, and the main reason I went to GCG instead of some of the local turbo shops.

You may be able to put in a claim through consumer affairs if they advised a power rating that isnt achievable (and provided your support systems are not the problem)

Got the Turbo through Turbo Australia who got it through GCG in Sydney.

I have asked the question as to why the diff in stated and actual pwr and they are getting back to me this week. So this will be interesting. As you say still a good turbo but not what I was after. Did a 13.2 qtr mile on Sat, best before was 13.4 BUT wanted to get into the 12s what a shit!!

[tang0]

i can vouch for the ease of fitting of the gcg high flow, takes about 4 hours start to finish with pretty basic workshop tools, you just need gaskets and coolant .. you might as well change the oil while you are at it as well ...