1. Login to disable the Ads!

SteamSpeed STX 78R BB N55 Turbo (aka stage 2.5) - specs & details

Discussion in 'N55' started by [email protected], Feb 8, 2018.

  1. sam@steamspeed

    [email protected] Lurker Vendor

    Messages:
    19
    Ride:
    Focus RS, Impreza RSti
    One of our long-time BMW customers has been rolling with our STX 67 N55 (stage 1) turbo for a while putting down 400+ whp with pump gas + meth. He has been asking us to make a N55 turbo capable of over 550whp, so we did. We call it the STX 78R which has a ceramic ball bearing center section (hence the "R" designation), and large compressor wheel with a 78mm exducer (hence the 78). It has a an estimated flow over 70 lbs/min, which should be good for over 550 whp on a N55 engine.

    Why did we invest the money to have a BB CHRA when a compressor wheel will flow what if flows even using a cheaper JB CHRA and hypothetically make similar peak power?

    The BB CHRA in this application will be way more efficient than using JB turbos of similar size. In practice, the BB CHRA will come in sooner, and give you a lot more response all over the power curve. It will be very noticeable daily driving, but will also improve lap times in sections where you are on and off of the boost. Also because the CHRA is more efficient, it will make more power everywhere where a JB turbo is less efficient like high back pressure situations for example. The added BB efficiency will have a lower heat load vs JB which also makes it easier to make power and tune.

    Here are the core specs on the SteamSpeed N55 STX78R (aka stage 2.5) turbo:
    Bearing System: custom ceramic BB
    • Custom Compressor wheel In:59 / Ex:78 (the size is between GTX3076 and GT3582)
    • Custom Turbine wheel In:60 / Ex:57 (The size slightly bigger than GT3076 - In:60 / Ex:55).
    • Flow capacity: 70 lbs/min (est.)
    • Estimated WHP: ~550+ whp
    • Release Date: TBD
    • Estimated Pricing: ~$2500
    • Core Required: yes (just the comp & turbine housings only)
    Stay tuned for testing data, and final dyno results. Barring on scheduling issues, or other setbacks, we expect to have some final results for you in the next 4 weeks.

    Oh, and here are the pictures:
    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG] [​IMG]

    [​IMG]

    [​IMG]

    [​IMG] [​IMG]
     
    Last edited: Feb 8, 2018
  2. doublespaces

    doublespaces Administrator

    Messages:
    5,968
    Location:
    AZ
    Ride:
    2009 E93 335i
    Sweet, I look forward to some results!
     
  3. ChrisNeil5

    ChrisNeil5 Lurker

    Messages:
    21
    Ride:
    2008 BMW 135i
    Nice to see some more advancement in the n55 platform
     
    • Like Like x 2
    • Agree Agree x 2
    • List
  4. James135i

    James135i Lurker

    Messages:
    24
    Location:
    Florida
    Interesting in for results as well.
     
  5. N55uk

    N55uk New Member

    Messages:
    8
    Location:
    Uk
    Looking foward to more info on this, we need more options on the n55
     
    • Like Like x 1
    • Agree Agree x 1
    • List
  6. doublespaces

    doublespaces Administrator

    Messages:
    5,968
    Location:
    AZ
    Ride:
    2009 E93 335i
  7. sam@steamspeed

    [email protected] Lurker Vendor

    Messages:
    19
    Ride:
    Focus RS, Impreza RSti
    Thanks everyone for the support. We will be doing some testing and validation in the next month or so. We'll try to keep this thread updated with useful install and testing data.
     
  8. terryd5150

    terryd5150 Specialist

    Messages:
    87
    Ride:
    2008 E92 335i 2009 E90 335i
    F-Series EWG application?
     
  9. sam@steamspeed

    [email protected] Lurker Vendor

    Messages:
    19
    Ride:
    Focus RS, Impreza RSti
    We can do either EGW or PWG using this approach.
     
  10. pabloN55

    pabloN55 New Member

    Messages:
    5
    Ride:
    335i LCI N55 E92
    nice:sunglasses:
     
  11. sam@steamspeed

    [email protected] Lurker Vendor

    Messages:
    19
    Ride:
    Focus RS, Impreza RSti
    Hey guys, thanks for the positive feedback. Even though we are in the early stages of testing this new turbo and it will probably be a few weeks before we have final dyno numbers, we have been getting phone calls from BMW owners very interested in the results and wanting to know when they can get their hands on our new STX 78R turbo.

    Even though this remanufacturing of the OEM housings is a path well tread by Pure and others, and their results are well known, and even though we are fully confident that our BB CHRA is superior to any JB system, we won't be doing a mainstream marketing push on this turbo until we have published turbo results. Nevertheless, there are several people interested in running this turbo before it goes mainstream. I salute you innovators and early adopters, we want to help you out. Read on. If you have a conservative personality that prefers to wait and only buy only after lots of people have it, that is ok. It is scary to be among the first.

    It is like buying the very first iPhone when it came out even though it cost $600 unsubsidized, vs waiting for the iPhone 3G or later models that you could get for cheap under contract. Personally, I didn't wait and bought the first iPhone at full price, but that is my personality.

    [​IMG]
    If you fall under the enthusiast and innovator category, we are open to allowing up to 10 people be among the first to run this BB turbo. This turbo is actually very expensive to manufacture, but we can still give you a solid discount to be one of the first. We have done similar programs for other models in the past. All we expect in return for said discount, is you publishing your final dyno results and your honest feedback about things like fit and finish, install process, etc. That is it.

    This is how it would work:
    - you would contact us and tell us you are interested in running this 78R BB turbo
    - assuming you meet the requirements, we agree
    -- your car mods can support at least 500 whp
    -- can get the final tune done within 90 days
    - you provide us a core, or we can source one for you
    - you order the turbo and the current price
    - we supply the upgraded turbo back to you within a week or so
    - after you have the turbo installed and dyno'ed, you publish your results, and provide feedback within 90 days
    - we refund a portion of your purchase price

    These are specifically what we are looking for in terms of deliverable:
    Deliverables:
    - feedback to us on install and fitment
    - feedback to us on the tune, with dyno results
    - published written result on your favorite forum(s). The post must include
    -- List of mods
    -- Final dyno plot
    -- At least one pic of your car with a SteamSpeed sticker somewhere on the outside. You are free to remove it later if you want.
    -- You honest opinion and impressions of the turbo, and maybe feedback from the tuner

    That's it.

    If you are interested, feel free to PM me, or call us at 1 (206) 607-9149.

    -Sam
     
  12. terryd5150

    terryd5150 Specialist

    Messages:
    87
    Ride:
    2008 E92 335i 2009 E90 335i
    I saw this listed for sale on your website.

    If we purchase straight from there (at the listed price), would we still be bound by the deliverables above?
     
  13. boostE92d

    boostE92d Corporal

    Messages:
    112
    Location:
    Houston TX
    Ride:
    12 335is
    Is this a product that could go on the n55 in the 640i?
     
  14. sam@steamspeed

    [email protected] Lurker Vendor

    Messages:
    19
    Ride:
    Focus RS, Impreza RSti
    No, you can do whatever you like. Still, other people in the community probably would appreciate the data points. For example, if your build is similar to theirs sans the turbo, then they can get an idea what it can do for them
     
  15. sam@steamspeed

    [email protected] Lurker Vendor

    Messages:
    19
    Ride:
    Focus RS, Impreza RSti
    Yes it can. We just need to start with the correct OEM core.
     
  16. sam@steamspeed

    [email protected] Lurker Vendor

    Messages:
    19
    Ride:
    Focus RS, Impreza RSti
    Here is our blog post about the install that happened this weekend. It should be wrapped up in the next few days.

    https://blog.steamspeed.com/2018/03/26/the-steamspeed-stx-78r-turbo-for-bmw-n55-install/

    Here are some of the action shots from the install:
    [​IMG]

    This is what SteamSpeed STX 67 “stage 1” looks like next to the STX 78R “stage 2.5.”
    [​IMG]
    [​IMG]

    Turbine wheel comparisons:
    [​IMG]

    Installed:
    The STX 78R "stage 2.5"
    [​IMG]

    SteamSpeed STX 67 "Stage 1" still running strong after over a year of hard driving.
    [​IMG]
     
    Last edited: Mar 26, 2018
  17. boostE92d

    boostE92d Corporal

    Messages:
    112
    Location:
    Houston TX
    Ride:
    12 335is
    We'll that opens things up quite nicely for my next car purchase.
     
  18. N55uk

    N55uk New Member

    Messages:
    8
    Location:
    Uk
    What are the advantages of the 2.5 over the pure s2?
     
  19. sam@steamspeed

    [email protected] Lurker Vendor

    Messages:
    19
    Ride:
    Focus RS, Impreza RSti
    The main difference has to do with the BB vs JB CHRA. With all other things being equal, a BB turbo will be more efficient, and more reliable.

    From the blog post:
    Base purely on inductive reasoning, this turbo should perform somewhat better than the currently popular Pure Stage 2 turbo: their turbo has wheels somewhat larger than a GTX3076R, our 78R is somewhat larger than a GTX3076R, they remachine the OEM housings, so do we, but the main difference is that our turbo has a BB center section, and Pure reuses the OEM JB CHRA. Given that the only main difference that impacts performance is that our has a BB CHRA, what does that impact?

    BB CHRAs have some standard advantages over JB: it is more responsive especially with transient boost, it is more efficient, it is more durable, etc. In this case, the biggest difference, I think, will be the fact that BB CHRAs can be stay efficient in spite of backpressure much better that a JB CHRA. Normally JB is fine up to 2:1, but BB can still be efficient at much higher ratios. This matters a lot in this case, because the OEM manifold/turbine housing is going to generate a lot of backpressure when you try to make over 500 whp.​

    From just looking at pictures, it looks like our wheels are a little bigger vs Pure Stage 2.
    [​IMG]

    We'll have to see what tuning and testing on the dyno shows ultimately, but the higher efficiency could make a big difference.
     
  20. pabloN55

    pabloN55 New Member

    Messages:
    5
    Ride:
    335i LCI N55 E92
    good taff, I wait for the logs impatiently
     
Loading...