Honestly, its too early to tell really. I just put 93oct in my car since it can't fuel E30 runs in cooler weather properly. I mean... It can... It just isn't something I want to be running lean AFR's on while trying to dial in a boost curve table. I yanked all the timing and dumped a lot of fuel just so I could get a happy boost curve before adding them back in and it wouldn't fuel the car correctly past 5800rpm.
So today, I filled it up with 93oct and loaded my old 93oct tune. Only got one log in; and just checked it a bit ago... Yep... Throttle shut on me at 3100rpm, and I killed the pull at 4300rpm ( cobb 93oct timing tables with -3.00 degrees trimmed off the top ). So I just fixed the throttle tables ( hopefully I don't have to keep readjusting them ). So I'll give it another shot tomorrow.
Point is... I'm tuning on 93oct pump gas. I can't promise epic results because I'm known for ditching 93oct pretty quickly for E50, but since my car can't fuel it, I may stick with it until I get me aux meth fuel system installed.
Turns out... The external gate with this new vacuum line is doing what I hoped it would. Just crossed my old "best datalog ever" 285whp run against one of my janky new runs from last night and compared them for "spool purposes".
The new setup at 4000rpm was at 26.4psi while the old setup was at 25.3psi. Not a real big difference. But keep in mind, this was a great log vs one from a brand new setup.
But then... I moved up a little.
The new setup made it to 28psi 500rpm faster than the old one. 4500rpm at 28psi vs 5000rpm for 28psi. I want to say I saw a different log yesterday that showed 28psi by 4300-4400rpm I think... Wait.. It was the datazap I posted !! 4413rpm with 28.01psi. So give or take 600rpm faster to 28psi. Also keep in mind, I still have the internal wastegate path in my turbine housing, I THINK ( I don't know, YET ) that some response is hidden in smoothing it out and welding it up like I've been doing for customers as well.
Now onto the thing about the external making noise. #1, even on my 93oct tune that will have lower boost and the gate opening up EARLIER than E30-E40 tunes, the gate should stay 100% silent until 4000rpm at WOT. If your running E85 mixes; than it could be quiet until 5000+rpm when it opens. Even at part throttle past 4000rpm, your gate will prob stay closed. Its only going to make extra noise if you ask it to. #2 I personally don't think its crazy loud. Maybe it is outside the car, IDK. #3 you gotta have some friends or a junkyard or ebay that has stock sport bike mufflers just laying around, they are stainless, and they make sport bikes almost silent, so they would DEFINITELY do the job. I love mine. Even if I got the option to go back to a stock catback and quiet air intake, I'd leave the wastegate dump because unless you MAKE IT LOUD, its silent. And its not like you just fall into 26psi with this turbo ( unlike the stock one ).
I will warn against using an external that is re-routed into the cat back. SRT4 guys have documented that it just about defeats the entire point if you plug it back into the catback. If your going to re-route it back into the catback, lets be clear, your doing it for 1 single reason PEROID. And that is to have 2-ports on your wastegate and to run the vacuum line setup I outlined. I don't think its worth it.
The internal gates do a good job. Nothing wrong with them. Mine has served me pretty well over the last 18months. But other platforms have proven the external gates make more power and sometimes increase response, and its only a matter of time before we know it as common knowledge as well.
Back to power figures... I'm going to keep doing what I've done from the start. What will your car do? I really can't say. I'm not your mechanic, I'm not your tuner, and I'm not the one who makes the choices of "what intake or catted downpipe". 240whp is a realistic number for everyone I think. Pretty sure some guys have made more like me. But if your going to handicap the car from front to back??? Catted downpipe.... 91oct only... Quiet catback... Quiet intake... IDK... You could end up with 200-215whp, which may sound bad compared to a lot of the "generous dynos" cobb may have put out, but real world basically stock cars + intercooler cars on 91oct likely struggle to hit 190whp at 5400rpm. 215whp at 6400rpm could actually be a huge gain at 6,400rpm. But I think if your going to limit the engine in almost every way possible, then.... Not sure a stock turbo upgrade makes sense. A $4500 big turbo can over come some of those things because it makes power without trying to hard, but when your stacking inches to get down a mile road, you can't skip 12 one-inch things and add a single 8-inch thing and expect the total to come out to 20-inches.
If your going to run a cat.... I super highly recommend a dumped external gate. If your going to run a cat and an internal gate, then... Just don't say the cyborg didn't live upto any grand promises. We have seen it. And it didn't work great. The downpipe was custom built to the highest quality, the cat was a "super awesome deluxe pimp juice infussed epic-cat with 17-trillion mega to cells" and it flowed like crap, it was a restriction, and the owner put a lot of nice parts into it just to replace it with a catless DP.
The external completely circumventing the cat and dumping a large amount of the hottest gases directly from the exhaust ports to the atmosphere; I think would make a catted downpipe an option. Other wise, I just can't recommend it
But I'll still sell you a cyborg if you want !!!! Lol. My car on 30% throttle to 4100rpm with -3.00 global timing pulled made 200whp at 4100 tonight on 93oct, so... Who knows, lol. I'm ok with being wrong