[SteamSpeed]

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 (aka stage 2.5) 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: PM us to participate in the beta
• Estimated Retail 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.

Update 1
It is still not a final tune, but here is some dyno charts:



Stage 2.5 Setup:
-FBO 2011 BMW 335i manual
– SteamSpeed STX 78R BB Turbo
– Single port meth
– Only 21 psi, 9 degrees of timing

Result:
– 456 whp, 518 ft*lbs torque


FBO vs Stage 1 vs Stage 2.5


Oh, and here are the pictures:

[SteamSpeed]

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/...w-n55-install/

Here are some of the action shots from the install:


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



Turbine wheel comparisons:


Installed:
The STX 78R "stage 2.5"


SteamSpeed STX 67 "Stage 1" still running strong after over a year of hard driving.

[SteamSpeed]

Originally Posted by N55uk

What are the advantages of the 2.5 over the pure s2?

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.


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

[SteamSpeed]

Click here is some initial tuning data logs.

Here are the 3rd, 4th & 5th revision on one chart. This is 92 octane with single port meth. They haven't finished dialing in the boost, and haven't really started working on the timing.
v3 - 16 psi - 476 whp / 512 ft*lbs
v4 - 18 psi - 517 whp / 534 ft*lbs
v5 - 19.5 psi - 509 whp / 574 ft*lbs

So, still working on the tune. I think the CHRA should have the capacity to make over 600 ft*lbs to the wheels, and also 600+ whp. I think the exhaust manifold will be the main limiting factor though. I think over 600 ft*lbs can still happen, but maybe 550 whp will be the flow limitation of the turbine housing/manifold. Stay tuned. We'll see how far we can take it.

Here is the data from the street pulls charted with VirtualDyno using the default settings, so take it for what it is. However, when we were testing our STX 71 for Evo X, the COBB logs charted with VirtialDyno vs the data logs from the actual DynoJet were fairly close. YMMV

[135idct]

price?

[SteamSpeed]

Originally Posted by 135idct

price?

Our plan is to have an initial retail price of $2500, but we are interested in building up a body of dyno results. If you are up for sharing your results, we will be offering extra rebates on top of the initial price.

-Sam

[JacquesN55]

Why dont you guys use Ethanol to test.

[SteamSpeed]

Originally Posted by JacquesN55

Why dont you guys use Ethanol to test.

It could be in the cards further down the road, but at the end of the day, this is a customer's car, and he wanted to start with pump gas.

[135idct]

Originally Posted by SteamSpeed

Our plan is to have an initial retail price of $2500, but we are interested in building up a body of dyno results. If you are up for sharing your results, we will be offering extra rebates on top of the initial price.

-Sam

actually im running efr8374 speedtech kit. ur price is good with good tune u will be near 600whp i think, good luck

[luchocamp]

Originally Posted by 135idct

actually im running efr8374 speedtech kit. ur price is good with good tune u will be near 600whp i think, good luck

I do not think that turbo could make more than PS2 on dynojet.
Pictures comparisson are not good. Zoom on the last one

[135idct]

Originally Posted by luchocamp

I do not think that turbo could make more than PS2 on dynojet.
Pictures comparisson are not good. Zoom on the last one

even if the same power the price is much lower

[terryd5150]

Originally Posted by 135idct

even if the same power the price is much lower

Price is exactly the same: $2500 + $1000 core charge.

http://steamturbochargers.com/index....r-bmw-n55.html

[SeanWRT]

Would you please explain how is your STG2.5 better than VTT STG2 with a genuine Garrett DBB CHRA please?

[135idct]

Originally Posted by terryd5150

Price is exactly the same: $2500 + $1000 core charge.

http://steamturbochargers.com/index....r-bmw-n55.html

pay 300$ more and buy the speedtech EFR7670 Kit, new manifold + 600+ whp

there's no competition when u talk about speedtech price for the WHP u get!

[Stoolz]

Originally Posted by SeanWRT

Would you please explain how is your STG2.5 better than VTT STG2 with a genuine Garrett DBB CHRA please?

I would also like to know this, also will this fit RHD?
Looks GOOD

[SteamSpeed]

Originally Posted by 135idct

actually im running efr8374 speedtech kit. ur price is good with good tune u will be near 600whp i think, good luck

Thanks for the kind support.

[SteamSpeed]

Originally Posted by terryd5150

Price is exactly the same: $2500 + $1000 core charge.

http://steamturbochargers.com/index....r-bmw-n55.html

The price is in fact $2500.

The core charge is $0 if you can provide one up front, or is completely refunded if send one in after the fact. You would pay the max price only if can't be bothered to return a core.

[SteamSpeed]

Originally Posted by luchocamp

I do not think that turbo could make more than PS2 on dynojet.
Pictures comparisson are not good. Zoom on the last one

I think it is already on its way to making 600 ft*lbs to the wheels. Based on Pure's published results, the PS2 doesn't tend to break even 500 ft*lbs even with higher boost. At the same boost levels, it is 100 ft*lbs lower! That difference is like a turbo 2-3 steps bigger with the same level of response!

This is what Pure has on their site:


In fact, our initial results look close to what an EFR 8374 can do in terms of torque:

[Pure Turbos]

Guys,

I see a lot of speculation in your thread, regarding our very popular Pure Stage 2. Let's see some true repeatable dynojet results of your Sumalaya brand Taiwan cartridge turbo, before making any claims. They pitched their BB cartridges to us April '15, we were not interested. Same brand as those n54 billet BB cartridge turbos that popped up, which had failure problems. Also, FYI your cartridge is missing a heatshield in your pics!

[SteamSpeed]

Originally Posted by Pure Turbos

Guys,

I see a lot of speculation in your thread, regarding our very popular Pure Stage 2. Let's see some true repeatable dynojet results of your Sumalaya brand Taiwan cartridge turbo, before making any claims. They pitched their BB cartridges to us April '15, we were not interested. Same brand as those n54 billet BB cartridge turbos that popped up, which had failure problems. Also, 59x78 is the size of our in house engineered PS2 compressor wheel. I surely hope your wheel profile doesn't exactly match our solidworks file created here in our facility. We will be checking on that. Also, FYI your cartridge is missing a heatshield in your pics!

We are aware that Pure Stage 2 is popular for N55, but popular doesn't mean better nessiciarily.

In this case of BB vs JB CHRA, if all other things are equal, the turbo with a BB CHRA will always be superior to the one with a JB CHRA. I think you will be hard pressed to make a logical argument to the contrary.

In fairness, data is just data. As we've clearly stated, this is just log data put into VirtualDyno with default settings, and to take it for what it is worth. We've also provided a link to the raw log data from street pulls if you want to poke around the data yourself if you are into that.

Never the less, I think the data is already clearly showing that this turbo can flow a lot more than the Pure stage 2 option with the data, potentially producing as much as 100 ft*lbs more torque at 18 psi. The logs show what the MAF is reading. Compare it to your own logs.

Again, here is the data. Note, this isn't even a finished tune.

I am not a patent lawyer, but I am the inventor of 6 patents (so far). In my experience, I can't see anything that Pure has done that is unique, novel, or hasn't been done before, so I doubt you have any technology that could be patent protected. If you had some unique turbo technology that hadn't been done 100 times before, I imagine that you would have filed for patent protection. If I am wrong, I would be very interested in seeing your patent filing numbers and reading the claims of said technology.

Originally Posted by SteamSpeed

Click here is some initial tuning data logs.

Here are the 3rd, 4th & 5th revision on one chart. This is 92 octane with single port meth. They haven't finished dialing in the boost, and haven't really started working on the timing.
v3 - 16 psi - 476 whp / 512 ft*lbs
v4 - 18 psi - 517 whp / 534 ft*lbs
v5 - 19.5 psi - 509 whp / 574 ft*lbs

So, still working on the tune. I think the CHRA should have the capacity to make over 600 ft*lbs to the wheels, and also 600+ whp. I think the exhaust manifold will be the main limiting factor though. I think over 600 ft*lbs can still happen, but maybe 550 whp will be the flow limitation of the turbine housing/manifold. Stay tuned. We'll see how far we can take it.

Here is the data from the street pulls charted with VirtualDyno using the default settings, so take it for what it is. However, when we were testing our STX 71 for Evo X, the COBB logs charted with VirtialDyno vs the data logs from the actual DynoJet were fairly close. YMMV

[Pure Turbos]

I disagree. I don't see any data that shows anything better. That's virtual dyno. That's not a real dyno sheet. Good luck.

[Jeff@Speedtech]

I try to avoid bs on forums when people don’t know what they are talking about, but I gotta step in here beings you are calling out our dyno runs. If you think stuffing bigger wheels into a hybrid through that stock N55 manifold, is going to be anywhere near our manifold with an 8374 EFR turbo, you have some learning to do. Here’s a few quick points –

-The 8374 EFR dyno run is being LIMITED to 24psi, that turbo can put out 35psi and make more torque and hp than a hybrid can ever dream of.

-Go cut open the stock manifold, and then realize why there’s little return in going to larger wheels than current hybrids, your peak hp is going to be capped by that stock manifold, argue all you want on that, but that is a fact (aka thermodynamics)

-We post SAE numbers from same car/dyno for honest comparisons, most others in this segment post STD because it reads higher, and then you are posting “virtual”…. and claiming to make the same torque as an EFR 8374 can make, come on dude… you might fool some people, but let’s be real here

-If you want to impress us, go instrument your setup with pre-turbo manifold pressure, and also turbo wheel speed sensor. For any hybrid to get anywhere near 500hp, through that tiny stock manifold, the backpressure and wheel speeds are crazy high, such that, about half of our customers buy our kit after having replaced their hybrid due to failures, leaking seals, etc. Good luck making the bearings and oil seals survive at that levels you are claiming.

-Kit costs –
For $3800, our kit includes all the components that eliminate the stock restrictions – EFR turbo (properly engineered for 500-1000hp), manifold (ours is 3 times the xsec area of stock), turbo inlet (over 2X increase in area), ********, boost pipe, oil lines, coolant lines, etc, now let’s compare to your offering:

For $3950+, your customer pays: ($2500 (turbo) + $1000 (core) + $3-500 (********) + $150 (hi-flow inlet) + etc for install kit) and get an untested hybrid that is reliable to what? 450?

[SteamSpeed]

Before everyone gets overly excited, we are simply providing data as tuning unfolds. If you are more sophisticated and want to dig into the data, hit the link and go for for it. If not, we just loaded the data into VirtualDyno using default settings. Take it for what it is and don't go crazy with it one way or the other. The tune has only had 4-5 revisions and isn't even up to 20 psi yet, and the timing hasn't been worked on. The data is is for pump gas; we haven't tuned e85 yet. Preliminary data is better than no data, right?

As for other purveyors of BMW turbochargers, this isn't an attack on your products. Business isn't a zero sum game. Consumers are naturally interested in how turbo products compare from different vendors.

Pure turbos have been on the scene for a while. They seem to be reliable, and people seem happy with their results.

Speedtech is newer to the game, but have a nice looking cast manifold. It isn't cheap to do that. The last new turbine housing we designed cost $8k in tooling, so hats off to you guys for investing in the N55 and making the tooling.

This is all goodness for N55 BMW owners. Personally I prefer to constructively work with other companies than bicker about products.

Furthermore, shipping a product is an engineering exercise of tradeoffs. Every approach will have advantages and disadvantages. A company that engineers products must weigh both, and then build a product that plays to their strengths. If an engineer product ships, there are some compromises built in. That is how engineering works.

[Dollar Bill]

Originally Posted by Jeff@Speedtech

I try to avoid bs on forums when people don’t know what they are talking about, but I gotta step in here beings you are calling out our dyno runs. If you think stuffing bigger wheels into a hybrid through that stock N55 manifold, is going to be anywhere near our manifold with an 8374 EFR turbo, you have some learning to do. Here’s a few quick points –

-The 8374 EFR dyno run is being LIMITED to 24psi, that turbo can put out 35psi and make more torque and hp than a hybrid can ever dream of.

-Go cut open the stock manifold, and then realize why there’s little return in going to larger wheels than current hybrids, your peak hp is going to be capped by that stock manifold, argue all you want on that, but that is a fact (aka thermodynamics)

-We post SAE numbers from same car/dyno for honest comparisons, most others in this segment post STD because it reads higher, and then you are posting “virtual”…. and claiming to make the same torque as an EFR 8374 can make, come on dude… you might fool some people, but let’s be real here

-If you want to impress us, go instrument your setup with pre-turbo manifold pressure, and also turbo wheel speed sensor. For any hybrid to get anywhere near 500hp, through that tiny stock manifold, the backpressure and wheel speeds are crazy high, such that, about half of our customers buy our kit after having replaced their hybrid due to failures, leaking seals, etc. Good luck making the bearings and oil seals survive at that levels you are claiming.

-Kit costs –
For $3800, our kit includes all the components that eliminate the stock restrictions – EFR turbo (properly engineered for 500-1000hp), manifold (ours is 3 times the xsec area of stock), turbo inlet (over 2X increase in area), ********, boost pipe, oil lines, coolant lines, etc, now let’s compare to your offering:

For $3950+, your customer pays: ($2500 (turbo) + $1000 (core) + $3-500 (********) + $150 (hi-flow inlet) + etc for install kit) and get an untested hybrid that is reliable to what? 450?

Impressive. Any plans to make a kit for F10 N55?

[Dollar Bill]

Originally Posted by SteamSpeed

Before everyone gets overly excited, we are simply providing data as tuning unfolds. If you are more sophisticated and want to dig into the data, hit the link and go for for it. If not, we just loaded the data into VirtualDyno using default settings. Take it for what it is and don't go crazy with it one way or the other. The tune has only had 4-5 revisions and isn't even up to 20 psi yet, and the timing hasn't been worked on. The data is is for pump gas; we haven't tuned e85 yet. Preliminary data is better than no data, right?

As for other purveyors of BMW turbochargers, this isn't an attack on your products. Business isn't a zero sum game. Consumers are naturally interested in how turbo products compare from different vendors.

Pure turbos have been on the scene for a while. They seem to be reliable, and people seem happy with their results.

Speedtech is newer to the game, but have a nice looking cast manifold. It isn't cheap to do that. The last new turbine housing we designed cost $8k in tooling, so hats off to you guys for investing in the N55 and making the tooling.

This is all goodness for N55 BMW owners. Personally I prefer to constructively work with other companies than bicker about products.

Furthermore, shipping a product is an engineering exercise of tradeoffs. Every approach will have advantages and disadvantages. A company that engineers products must weigh both, and then build a product that plays to their strengths. If an engineer product ships, there are some compromises built in. That is how engineering works.

It would be great to have some more F10 N55 turbo options! I'm subscribed.