Exactly! Is the Ford/Navistar flange style as efficent as a T4 in this scenario? In other words, does it proved the same amount of energy or more on the exhaust side? I have been wondering the same thing the past few months.
The t4 flange on the SXE itself has VERY LITTLE to do with the performance success of the SXE turbos (or any turbo for that matter).. if it did then everyone would love the OBS turbos because they are a true T4 turbine housing straight from the factory. But we all know how well the obs turbos perform. You would NEVER see someone take the time to swap in an OBS t4 turbo into a superduty because it is a t4 turbo. I actually know guys who swear by the t3 gated housing over the t4 housing but that is a subject for another thread/day.
The whole "t4" thing gets pretty confusing because of the fact that many guys calls it a "t4 swap" when it fact you are swapping on a better performing/more advanced turbo... not just a t4 flange.
With that said the "vband" style housings perform very well and are sold in a wide variety of applications. It is NOT a ford/navistar flange. They are actually getting really popular in other applications because of how much easier they are to install and how well they work in other applications. Don't believe me... feel free to google search.
Here is a link for those guys wondering about it not being a ford/navistar flange
https://frsport.com/Garrett-Divided...MI4Nnb9bTB1gIVVrXACh1PRwEXEAQYASABEgIqgfD_BwE
Also here are some links to other platforms outside the diesel world talking about how well they work
http://www.supraforums.com/forum/showthread.php?978353-Turbo-inlet-flange-v-band-vs.-T4&
Now the comp cover... the comp cover on the superduty covers seem to flow very well. It has huge volutes and a 1.0 A/R. It is more similar in size to what you would find on an s400 turbo. But honestly the compressor cover science is limited and not as "obvious" as the turbine housings.
So, now that we have gotten past the turibne/comrpessor housing. I can tell you that changing over to the SXE style wheels has made a HUGE difference. INCREDIBLE according to all testers/customer. Turbos spool WAY faster, run cooler, make more boost, etc.
But I can't tell you how they compare exactly to a genuine SXE t4 turbo because we have not tested it back to back. And even if we did then there would always be the "nay sayers" about how something was not done right, tuning wasnt right, probably had a boost/exhaust leak, etc (on both sides)
There will always be pluses and minuses to each setup. Cost vs ease vs variety vs etc... I am not out there making threads and boasting about how the t4 kit is obsolete or pointless. We are just doing our best to make the best drop in turbos possible and keep pushing our line forward
It could be said that a lot of the performance gains from a t4 kit could come from better flowing cac tubes/spyder setup. It could also come from better flowing up pipes and/or the fact that you finally fixed all your boost/exhaust leaks for sure while changing out everything. That could be why some guys have great luck with even the old garrett 38r while others hate it and switch to the "t4 turbos".
I would rather this not turn into a pissing contest thread... I always hate those. But if anyone has anymore specific questions then I will try and answer them without causing the typical bashing thread that these always turn into.