Does anyone have any experience with Steam turbos? I'm trying to figure out which direction to take my turbo upgrade and am considering all contenders including this Steam STX 78R, Pure Stg 2, and G-Power. I like the idea of a ball bearing CHRA for faster spool up. Can you get a ball bearing center housing upgrade on a PS2 or G-Power?
http://steamturbochargers.com/index....r-bmw-n55.html
From their website:
Quote:
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
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