Technical Turbo design discussion and opinions

Rob09msport

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Pretty sure that's covered. You can't buy a car with 100k and not expect rattles but all the reputable vendors are way past wg rattle we talking volutes wheels and boysen baby
Seriously tho if we could figure out the troll prob with this forum thing shit 2018 would be a GREAT year.
 
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Rob@RBTurbo

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Until someone solves the rattling waste gates, you are pissing in the wind. How about this Rob. I'll buy your turbos at 50% of asking price, and I will send $200 dollars a year until they start rattling?

No offense, btw. I'm still deciding between a small bottom mount and what you guys have going on.

This is great and can see the new threads appearing now... "Don't want to make any payments on these RB Turbos, so how can I make them rattle?"

Answer: There's plenty of ways, outside the turbos, that can get it done for you.

If it is any consolation we have been selling these turbos longer than any other, for nearly 9 years now, and can count on one hand the amount of rattling complaints we have heard over this time. Our WG parts are not bought for $75 on Ebay, we actually machine them ourselves on our own CNC Mills/Lathes.

And for those on the never ending quest for an everlasting gobstopper in every part they purchase for their BMW, it is time to face the music and realize these things are maintenance nightmares- literally everywhere you look. So you either accept this maintenance as part of your ownership or you sell and buy a Honda or Toyota to swiftly end the worries. There is always going to be some caveat no matter what you do, and ultimately as long as you keep your vacuum actuation system in check the new wastegates on the new turbos would be the absolute least of my worries.

Thanks,
Rob
 
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Panzerfaust

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Yeah, I have no idea where this idea that all twins will rattle comes from. Any of the reputable builders solved that issue years ago (MMP, VTT, RB, Pure...) - it's the cheaper "upgraded" turbos, Ebay turbos etc that have the issue.

Plenty of engines besides N54s use internally gated turbos without rattle, BMW just had a shitty setup longevity-wise from the factory but even then not everyone's turbos ended up rattling horribly. My car had 120k on it when I upgraded the turbos, my seals were starting to go bad but the WGs didn't rattle and I could still hit 18PSI.
 
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boostE92d

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Meh, both of my 335s have been reliable. Definitely not "maintenance nightmares." Honestly, my only real complaints are water pumps and waste gates. If you say yours don't rattle, then I gotta believe you, right?
 

boostE92d

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I do feel like RB's are a good bang for your buck turbo option. Also the company isn't owned by Tony. Two big plus marks in my opinion
 

Asbjorn

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Unfortunately when the masses get conflicting viewpoints from multiple vendors, it just gets very difficult for truth to prevail. We've certainly no issues with telling it how it is, and well agree that most of what we see thus far with the Hydra setup is looking great.

As anyone who can technically follow along with this discussion can understand, what we've always been saying (and are often scoffed at for doing as such) is that the Zage/GC 1.0 (and subsequently cheaper copied GC 2.0's) have essentially the same meaningful A/R as the OE turbos. Unfortunately when one looks at a picture of the turbine housing inlet and manifold outlet mating connection, they however say "WOW look at how much more flow this setup has!" and then all promise of understanding goes out the window. They are not considering that the A/R (the actual A at Radius intersect) inside the turbine housing is basically the same size as OE; and this is the main restriction of any turbo setup from a power production perspective. Hydra seems to have a firm grasp on this and likewise surely would agree as well.

Anyway long story short we could've been selling those GC 4.0cm2 housings for well over a year now, but have opted out of them as there was no point unless we too want to join in the business of bullshitting customers. So yes when we see an OE housing at 3.9cm2, a Zage/GC1.0/GC2.0 at 4.0cm2, you are going to hear "not really much of an improvement" from us as that is the truth. Now if we see an aftermarket cast housing with an actual A/R improvement, then we of course will say "there's certainly potential for more power at some trade off of transient response" and the positive thoughts for bigger powered options will begin to flow.

A REAL game changer will come in the form of a perfectly matched setup, meaning all components from inlets to outlets, wheel designs with matching A/R potentials, etc.; and this is the closest thing that has been put out there to date IMO. The MMP 1K setup went off in the right direction by addressing the actual A/R but seems to have really went overboard IMO... but more will have to come with that as more information is shared.

Rob

This makes me curious - how are the S55 housings like in comparison? Also 3.9cm2?
 

Rob@RBTurbo

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This makes me curious - how are the S55 housings like in comparison? Also 3.9cm2?

S55 are 6cm2 which is a much more desirable housing than N54 or most of the cast aftermarket equivalents. It however does have some limitations in regards to hybrid upgrades, regarding Turbine wheel sizing primarily.

PS: OE N54 are 4.9cm2- I have had some typos the past few posts in that regard. The other current aftermarket "larger options" are ~5.0cm2, but being 2-piece could be ported to eek a bit more flow out of them. EDIT: Corrected prior posts accordingly.

Rob
 
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boostE92d

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I guess that's a matter of perspective. I'd buy a bag of dog poo from Tony before buying anything from Rob.
Well... There you go, lol. I'm quite sure you've been at this at least as long as me (if not longer). I definitely recognize you from threads completely devoid of drama and full of information on making things work on my favorite car.
I mean, I don't necessarily agree, but it's noted.
 

Panzerfaust

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Well... There you go, lol. I'm quite sure you've been at this at least as long as me (if not longer). I definitely recognize you from threads completely devoid of drama and full of information on making things work on my favorite car.
I mean, I don't necessarily agree, but it's noted.
They're both knowledgeable about the platform, and each has their strengths in regards to specifics. Yes Tony used to get defensive when people would bait him and he liked arguing. The thing that turns people off about Rob is he sees his way as the only way even when goals are entirely different and doesnt mind belittling people who have different views or prove him wrong, he just doesnt do it with as many creative crosswords as Tony did.

That said, VTT have really made some progressive products for the platform in the past few years and if you wouldn't buy something from a vendor just because you don't like the way they posted years ago, you're really only limiting yourself imo.
 

Rob09msport

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They're both knowledgeable about the platform, and each has their strengths in regards to specifics. Yes Tony used to get defensive when people would bait him and he liked arguing. The thing that turns people off about Rob is he sees his way as the only way even when goals are entirely different and doesnt mind belittling people who have different views or prove him wrong, he just doesnt do it with as many creative crosswords as Tony did.

That said, VTT have really made some progressive products for the platform in the past few years and if you wouldn't buy something from a vendor just because you don't like the way they posted years ago, you're really only limiting yourself imo.
Usually rob is right he can just really make you wish he wasn't sometimes lol . Devils advocate though im sure it's really frustrating when people belive hype and cheerlead abstract facts that are out of context and overall is just marketing.
 
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Panzerfaust

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Usually rob is right he can just really make you wish he wasn't sometimes lol . Devils advocate though im sure it's really frustrating when people belive hype and cheerlead abstract facts that are out of context and overall is just marketing.
I'd agree that he's usually right on things like the PCV system and OEM designs, sure. But in areas where he has little interest or no competing products he usually just has "our guesses" or "we think"'s, even if it's been proven the opposite. Maybe I'm biased but I think my log of the 1Ks hitting 16psi at 3200rpm is a good example when he had earlier stated that they don't even hit 15psi until the same time a big single turbo does, not to mention a handful of other recent examples on these forums.

That said, I'd like to reiterate that he does know what he's talking about a lot of the time.