Jump to content
SAU Community

Would A 2860 -7 Or -9 Benefit From Ported Exhaust Housing?

ZT-R

By ZT-R,
in Engines & Forced Induction

 Share

Recommended Posts

ZT-R Enthusiast

ZT-R

Posted
Posted

Hey guys I talked to ATP turbo and they said they will soon have the GTX2860 as a bolt in for the skyline. I am looking for 450-500whp in my S30 240z. I know that kind of power is typically the GT2860-5 which has 76 .64 a/r turbine. the -7(n1) and -9 (gtss) have 62 trim .64 a/r. Do you think by extrude honing the -7/-9 .64 a/r housing that would have any benefit to the turbo still using the smaller .62 trim wheel? or is the wheel what is keeping this turbine back in power?

Thanks.

lee

R31Nismoid Grand Master

R31Nismoid

Posted
Posted

lol hold up - you know what it'll be. Just a milled housing to suit.

It won't be a proper Garrett one, and will likely mean rubbish performance as we've seen in the past.

Do you think by extrude honing the -7/-9 .64 a/r housing that would have any benefit to the turbo still using the smaller .62 trim wheel? or is the wheel what is keeping this turbine back in power?

The -5 turbine and the -9 turbine are the same size... They both use the 76 trim wheel.

The -7 uses the smaller trim.

All honing will do, is hurt the blistering response - which is why you make that turbo selection in the first place.

ZT-R Enthusiast

ZT-R

Posted
  • Author
Posted

On garret website turbo 2859r (707160-9) shows a 62 trim .64 a/r

the -7 ( (N1) 707160-7) 2860r shows 62 trim .64 a/r

the 2860-5 (707160-5) show a 76 trim .64 a/r

the site is sort of misleading because 2860r are listed as 2860r (1) 2860r (2) 2860r (3). the GTSS is the 2859r so there is 4. i believe the 2860 (3) is essentially a disco potato, its part number is 739548-9 so dont confuse the to -9 turbos.

ZT-R Enthusiast

ZT-R

Posted
  • Author
Posted

Hold up. Any more info on this?

From ATP email today.

"They would be just like the -7 and -10 turbos. You won't get the GTX comp housings with built in anti-surge though and so these will have the skyline style compressor housings with 2 bolt inlet and 2 bolt outlet and no way to integrate the anti-surge machining.

discopotato03 Grand Master

discopotato03

Posted
Posted

Works like this , you have the basic T28 turbine in I think 62 trim and a few turbos got the nice GT28 NS111 turbine in 62 trim as well . It has fewer more open blades than the normal GT28 turbine and in performance apps is a good thing .

I don't have time to look ATM but off the top of my head the GT2854R/GT2859R/GT2860R (707160-7) turbos got the 62T NS111 turbine .

If you see a GT28 based turbo with a 76 trim turbine its the larger trim version of the NS111 like say HKS spec Garrett "GT2530s" get .

Many won't agree but my take on turbine and housing size choices is more about where you want the boost and torque to be than maximum power output up high - in a roadie anyway .

Also I doubt theres room on an RB26 style compressor housings to incorporate port shrouding and make it work with a GTRs inlet plumbing .

You also take the risk of going out on a limb with GTX compressors and plain comp housings .

Its one thing to increase a compressors pumping capacity and another to bank on it not surging . The only way to know is to try and its an expensive exercise if it does surge .

The factry style turbo layout on an RB26 was designed for a purpose and the tight packaging doesn't leave much room to make major alterations . IMO you need to try and get them right the first time and if it was me I'd go conservatively with something known like -9s .

A .

ZT-R Enthusiast

ZT-R

Posted
  • Author
Posted

Not the exhaust manifold porting, the turbine housing for the turbo. I really would like the -9 I think but I havent seen any rwd numbers close to the 500 mark. Thats why im wondering if you ported the housing of the -9 turbo from a .64 A/R to something like a .72 A/R or something (light extrude hone), if it would gain any up top, I know you would probably loose a touch of spool though.

discopotato03 Grand Master

discopotato03

Posted
Posted

Turbines and their housings are always a compromise , where you gain at the top you lose at the bottom . AFAIK Garrett and HKS only made RB26 specific turbine housings in 0.64 A/R and its questionable that porting them would make much difference .

I think the way to make an RB26 wider ranging without increasing its capacity is to give it some form of variable cam timing and play with fuel octane and static CRs . Ideally more cubes but thats expensive to do as well .

A .

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
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • Rezz
      R35 GT-R production ends after 18 years

      By Rezz · Posted

      Order for the 2025 model R35 GT-R were accepted from 3rd March and 26th August the last order rolled off the production line at the Tochigi plant. Concerning the R35 GT-R replacement, current Nissan CEO Ivan Espinosa said "Nothing has been decided about the GT-R at this time, but we are well aware that everyone is waiting. The GT-R will evolve and reappear in the future. Please be patient until that day comes." Nissan has a lot of issues with management and finances so take Espinosa's words with a big grain of salt. From what discussions I've had and read about here in Japan, not a lot of people are confident about Nissan's future, let alone the next GT-R. 
    • Kapr
      ECU sees many times the speed than speedo does (R34 swap)

      By Kapr · Posted

      Thanks. We getting some parts along too so he will be solving the speed issue like next week so i will let you know what he came up with.   
    • MBS206
      R34 25GT Engine Light 21

      By MBS206 · Posted

      21 is explicitly the coils detected as the issue. Is it guaranteed the actual issue? No. Just the ECU thinks it is. When you say rattling, describe it better, get an audio clip as best you can if possible.
    • CF.Panda
      R34 25GT Engine Light 21

      By CF.Panda · Posted

      Yea got me coppers. Bad news is I just put them in and the car still has the light and shakes. I also noticed I hear like rattling coming from the exhaust piping right under me. Does 21 also have a possibility of being O2 sensors?   So, coil packs are good, the harness is good, the MAF is working, and obviously the spark plugs just replaced and working.
    • MBS206
      RB25DE NEO with Haltech ECU

      By MBS206 · Posted

      Make sure you drop the GTT base tune back in, and set your injectors again, this will remove anything playing up with it you may have removed. Possibly lean there as it's normally a fast transient going THROUGH atmospheric pressure, and a turbo motor would then quickly go richer as boost builds. The only worry you MIGHT have is ignition timing, as the DE is higher compression than the DET from memory. But again, you're not in boost, so the DE motor will be a lot more forgiving at atmospheric.   Get Murray, Kinkstahs, and Johnny's input on tuning haltechs, those guys have played with tuning enough in the past to be able to help now you're past the trouble shooting stage of the MAP issue
×
×
  • Create New...