My apologies Fillipo, my original intention was simply to state my opinion and offer the reason why I thought so but that was questioned and I can admit I may have fed into the fire a little here.
I still think for the most part any modern twin ("hybrid" or fully cast, no-OEM parts) setup will last a long time with the right supporting mods and proper tuning, some can just handle higher flow and PSI than others by design. Other than that, if you're not running *everything* required (properly sized upgraded inlets & outlets, no closed air box, new oil drains, proper install etc) and/or have your turbo spinning right at or past its efficiency range then any turbo will see a shorter life span regardless of manufacturer. Whether its MMP, Pure, RB, VTT or Hydra the proper equipment and tune is what matters most when factoring in reliability. Yes those 3 sets of RBs obviously suffered catastrophic failures, but I've also never heard of anyone else attempting to run RB or really any other stock frame turbos at 30psi which surely none are made for. 600, 630, 650 are all pretty damn nice WHP numbers and there's plenty of turbos capable of that but when I think "high HP" on the N54 I think 700+, and I dont think it's safe nor reliable to push any stock frame turbo that far. A larger A/R housing to go with those upgraded wheel sizes and preferably a better exhaust manifold is surely better suited for keeping backpressure levels and over spinning at bay if you're trying to hit that magic lucky number or higher.
Good post sir and very much agree. You see these things I say are based on our own experiences and things we see others doing the same later down the road. A go first and hit the wall first if you will. Some of these experiences were intended to be platform advancements for the time, but later turn out to be failures overall. Some of these same failures were later copied by competitors, who eventually met the same fates, and whom mostly still still sell them today without fully addressing the real reasons of why they are still failing. As such our reliability thread entails these things we've learned, spread across our product portfolio, over the past several years (and certainly NOT all eternity).
Once upon a time we were the first ones to start making "Stage 3 Type" N54 turbos, dub'd the Super RB EVO's in later 2014, and began shipping them production early 2015. This was documented mostly here:
Update: Super RB Evolution into Stage 3 type Twin Turbos>>> N54
www.n54tech.com
With these setups we made full plumbing solutions, and shoehorned the largest wheels possible into the housings (literally crammed them in, regretfully). As we have full machining facilities and didn't require casting, it was easiest to be the first to draw here. Keep in mind this was amidst a time of heavy platform competition, mainly for power, so running in that direction was the first priority and there were a LOT of supporters pushing for it as well. Everyone wanted that dyno sheet for sure, the power hungry N54 enthusiasts were thriving and were absolutely elated with what was happening.
Anyway fast forward about a year or so and we were beginning to see very high fallout from these breeds, including the Super RB Stealths (which from a wheel perspective were identical). Unfortunately these issues don't usually just sprout up overnight, while some can take months others may take years. This is where we learned that if you start seeing ANY failures in under 9 months as a manufacturer, it is time to really evaluate and/or reconsider the product. Or better yet, beta test it, as we did heavily with our RB Twos (which have been 100% perfection to date nearly 2 years later). Eventually when you start seeing a common failure mode, you know it is time to do something which in our case was to pull the plug on new sales and try our best to remedy what is out there via servicing.
As you can see in the thread above, right around a year later, there were no real updates thereafter. Well that is why, we had no interest in selling any more of them. Interestingly enough and right about the time we pulled the plug, a new competitor pulled up with the idea of copying the exact same concept- the new platform "Stage 3's" if you will. So yes it was fun sitting back and watching that go basically in the same direction. And while they also performed pretty decently, just the same the reliability and engine distresses really was not worth it when said and done. History had repeated itself.
Alongside that was a new cast offering, from Zage in Taiwan, which looked like a great concept being fully cast and "redesigned from the ground up". Unfortunately it took a while for us to get our hands on a set, but at the same time once we did we found they were not really much of an improvement... and had the same exact "shoehorned" effect of too large of the wheel for the housing. The frame for the R (for Radius) is exactly the same as OE and the A (for A) is only marginally larger, worse yet the material was still not there for a proper diffuser to be machined. The only prop it had was a larger collector, which although is a plus it would be much more meaningful if the housing had more flow potential. In short, another bust and not much value added IMO, and we obviously were not interested in buying into this one. The writing was on the wall history would yet again repeat itself. It did and continues to do so.
Anyway more cast stuff is on the horizon and some already shipping, there is no doubt if done right it is the way to go for those chasing a reliable 600+whp on twins. Time will tell but for years this platform has been striving for big power out of twins and suffering tremendously in the process as things simply had not been done correctly yet. Things need to be learned from the mistakes of the past, however IMO if things aren't right it is time as a vendor to pull the plug until they are corrected. Some vendors are not able to do this it seems, and the N54 platform twin big power chasers continue to suffer in the process.
The Hydra housings are the first released cast N54 product that we have seen that 100% has a larger frame (R= Raduis) and nozzle area (A= Area). For this reason we feel that they were going to be the first ones to really see some significant gains, especially on the N53 headed setups with the full manifold. IMO a full sized collector is going to be ideal for these housings, as they have the ability to MOVE the air. Remember making power is not about PSI, it is about AIRFLOW. PSI is simply the measurement of restriction of the hot side, the idea is to move as MUCH airflow through this system at the lowest possible PSI to make the power- yet retain tolerable turbo response. At the end of the day more PSI is going to lead to more Backpressure, and excess Backpressure is the ultimate killer of turbos and engines.
Thanks,
Rob
