Jump to content
SAU Community

Recommended Posts

I reckon that turbo can support a lot more airflow (power potential) than an RB25 could reliably withstand so a bit pointless unless you beefed up the internals . To get the boost threshold down to an acceptable point for a road car would mean using a small AR ratio exhaust housing so the 750 odd Hp compressor is wasted .

As Chris said you don't hear of these things surging , guesstimate only but HKS may have done the cover like that knowing that heroes like to put big turbos on small engines with small AR exhaust housings . By small I mean under 2L 4's .

Not sure what you mean by "efficient boost" . Airflow makes for power and pressure just moves it along . I have been told that these wheels make their greatest efficiency at surprisingly low pressure and flow rate but the "islands" are very long meaning that they work over a wide range of flow and pressure ratio . Its a pity Garrett dont make a 76mm version of this wheel because it would be a good thing with a GT35 turbine .

Cheers .

the holes on the comp cover are a workaround for compressor surging

it allows air to enter onto the compressor wheel on the outer edge to balance out the some of intake sucking, which is commonly associated with surging. think of it as an anti surging device.

the bulk of the air enters the snout, thanks to the vacuum effect of the compressor wheel sucking in air, but a very small amount enters through the holes also to side step around surge

:)

The ported holes are there to assist in reducing compressor surge so that the air enters the compressor housing around the compressor not through it.

They are also meant to help stabilise the shaft when at high shaft speeds to help reduce turbulance which creates vibrations.

They are there to help at a very high level of boost and if boost preasure is run outside the capacity of the compressor wheel creating surge then the vacuum effectivly bypasses the air through the comp ports and past the compressor wheel.

Also will this turbo go good on a rb25det or will there be a bit of lag, also what will

be the max efficient boost.

Depending on the size of the rear exhaust housing I have a t04z with a.81 housing and Ill be running 2bar of boost through my RB25 hopefully It will be at full boost by 4 .5 to 5000 rpm

I'm skeptical will see 2bar @ 4500rpm with a t04z... you'd need some very well matched cams and some agressive tuning to do so.

Probably closer to the 5k mark as you say.

I saw 24psi around 4200-4400rpm depending on gear/load with a GT30/.82.

However but that wasnt street fuel so it had some super angry timing numbers screwed into it... cause we could :dry:

Definately post results when your done though dude.

It'll be interesting to see vs what i had with the GT30 :D

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Yeah i found that alot of parts can be wrong or "very" hard to get the real right one. I already bought some brakes years ago on me "old" GT calipers and they were wrong too 😄  I told them too. Even send them pictures...but they said "EBC catalogue has them on my car... So i dont know what their answer will be. I call monday them and let them know that they are really not on my car. If they were they would be already on a car...
    • Welcome to Skyline ownership. Yes, it is entirely possible parts websites get things wrong. There's a whole world of inaccuracies out there when it comes to R34 stuff (and probably 33 and 32). Lots of things that are 'just bolt on, entirely interchangable' aren't. Even between S1 and S2 R34's. Yes they have a GTT item supposedly being 296mm. This is incorrect. I would call whoever you got them from and return them and let them know the GTT actually uses 310mm rotors. Depending on where you got them from your experience and success will obviously vary.
    • Hi...a bit a "development" on the brakes. I spoke to the guys where i get brakes from...and they are saying that 296mm EBC are for R34 GT-T. I then went to their site: https://www.ebcbrakes.com/vehicle/uk-row/NISSAN/Skyline (R34)/ and search for my car(R34 GT 1998 - it has GTT brakes) and it show me this USR1229 number and they are rly 296mm rotors... So now iam rly confused... The rotors i have now on the car are 310mm asi shown... So where is the problem? Does the whole EBC got it wrong or my calipers are just...idk know what?  
    • Oh What the hell, I used to get a "are you sure you want to reply, this thread is XX months old" message. Maybe a software update remove that. My bad.
    • This is a recipe for disaster* Note: Disaster is relative. The thing that often gets lost in threads like this is what is considered acceptable poke and compromise between what one person considers 'good' looks and what someone else does. The quoted specs would sit absurdly outside the guards with the spacers mentioned and need  REALLY thin tyres and a LOT of camber AND rolling the guards to fit. Some people love this. Some people consider this a ruined car. One thing is for certain though, rolling the guards is pretty much mandatory for any 'good' fitment (of either variety). It is often the difference between any fitment remotely close to the guards. "Not to mention the rears were like a mm from hitting the coilovers." I have a question though - This spec is VERY close to what I was planning to buy relative to the inboard suspension - I have an offset measuring tool on the way to confirm it. When you say "like a mm" do you mean literally 1mm? Or 2mm? Cause that's enough clearance for me in the rear :p I actually found the more limiting factor ISNT the coilover but the actual suspension arms. Did you take a look at how close those were?
×
×
  • Create New...