So we hit the dyno this weekend with the RB30DET now using the .91a/r S362SX-E with the 76/68 turbine and unfortunately other issues stopped us from "sending it" but it still gives a pretty solid impression of the impact (or lack thereof) on spool and also the flow difference. Anecdotally speaking EMAP is way WAY reduced versus the old S360SX but it's hard to know how much of that is just the big improvement in compressor flow, however with the same boost control solenoid duty cycle we previously had to run just over 1bar it is now holding 20psi and making >100whp more haha. I put a speel here if you are curious: https://www.sau.com.au/forums/topic/...drunk-rb30det/

 

Thanks for sharing, but it was a little hard to follow. The older turbo had two versions of the turbine wheel with one being the same as what was passed on to the S362-SXE according to AGP. The compressor is similar, but the SXE has an improved aero so should flow slightly more although not much. Curious as to the spool on the 3L and I assume this was a TS turbine housing?

 

The 61.4mm SX-E compressor flows ~15% more than the old 60mm SX one - is that what you were referring to? I would call that more than slightly more if so.

The spool is good, I mentioned that in the wall of text - as well as a dyno plot and log... it was hitting 1.5bar by 3700rpm on a 9 second sweep. On the road it feels really good, too. It's pretty comparable with a GT3582R, I'd say. The .91a/r housing is a divided housing.

 

I find it weird that they say "adapted to the SXE line many years ago", since the SXE has only been out for what, three or four years? It's hard to believe that the turbine wheels are the same "cup tip" from the SX line, given that they didn't make much of a difference on those turbos and they seem to breath much better on the SXE line. I realize that part of that is due to a more efficient compressor stage meaning the turbine has to do less work, but it seems more significant than that. This entire paragraph is conjecture though, hah.

Thanks for sharing this, it was quite informative!

 

You clearly know more than AGP, who is a Borg Warner distributor. Interesting that you say conjecture, when that is what you provided. If you have actual information to dispute AGP then please provide.

 

Ahhh the two turbine options for the S300SX range - when I started writing that rant I had been wondering whether or not to mention that option and clearly just forgot about it and focussed on what was relevant to the exact comparison we were doing at the time. I never found a 60mm S300SX with the "cupped tip" option but I guess it doesn't mean it didn't exist, I feel like that was an option which was mainly provided with the likes of the S363SX, S362-FMW etc but a lot of the old pages with those advertised seem to have disappeared and I've definitely found that people who sell and profess themselves to be authority on them provide incorrect information.

One of the reasons I felt it worth clearing a lot of what I could clear up with this test was that one of the big Borg Warner dealers told me unequivocally that ALL the SX-E range use the same flat tip turbine wheels from the S300SX range. If I HAD to bet what was happening, I'd actually wager that it's the same cupped tip turbine which AGP are talking about but I think that really it's all nit picking now, basically the important thing is we know what the SX-E essentially has and that offers good flow with no cost to response compared to the old flat-tip S300 turbine which was painted as the "better response" option at the time it was more current.

Here's the old comparison that used to go around the net from the pre-SX-E days:

And here's my comparison of the S300SX 83-75 wheel with the S362SX-E:

No worries, thought it might be interesting and get some more constructive info out for those that way inclined.

 

I wasn't trying to say that I know more than AGP or even state anything factual at all. I was merely questioning the accuracy of the statements they made. When I said this paragraph was conjecture, I meant the paragraph that I wrote, not the one you did. I've had distributors/dealers/whatevers be wrong about the products they sell before, especially when it comes to turbos.

Ah yes! I was looking for that old picture, and couldn't find it for the life of me. Now that you found it, it does seem like they are the same turbine. Very interesting to see how much a more efficient compressor stage helps turbine efficiency/work capacity. Yes I would agree that the big picture here is that we now get a 78lb/min turbo that responds just like the old 60lb/min one.

 

My apologies....all good.

 

This testing kinda imho so far proves some of that, or at least clears up some confusion regarding this kind of thing. While I would have loved to have been able to turn it fully up (and fully intended to) it still has managed to go some way to proving that the exhaust side on these is more capable than what some of the advice around suggests. [/quote]

Definitely, while I've known academically that it's a thing - it's only been more recently that I've really started appreciating exactly how much compressor efficiency can directly affect the turbine's work. There are so many cases where turbine flow has been blamed for setups where high EMAP is potentially largely, or entirely down to the compressor stage.

On that note, I still haven't quite worked out why or how Borg Warner choose to "cut off" their compressor map at places - it's clearly not just compressor speed related... if anyone has any wisdom on it I'd love to hair it.

If you compare efficiency for efficiency then the S363SX-E has basically no worthwhile advantage over the S362SX-E, at least if you are going to use it on an engine like the one we were testing. The compressor map extends to higher flow rates, but only because they've mapped down to 54% compressor efficiency as opposed to 58/60 on the 61.4mm compressor.

What I wonder is what would 61.4mm map look like if they kept going to 54%, or is there perhaps a reason why they wouldn't or couldn't? I would like to think that it isn't that they had invested in making the wheel and didn't want the efforts to be fruitless, so just dropped their standards a bit when making the map to make it look better.... granted the 63mm is much more effective at higher pressure ratios, just they are ratios which won't be much good for engines which flow fairly well.

 

I ran into an issue as both my header and midpipe cracked in a few spots so I have narrowed it down to the fact I don't have a flex section in the exhaust until after the midpipe. On the short runner setup I had a flex section right after the 90deg from the turbo pretty much in the same spot as the stock pivot point. I've ordered and received a 3.5" bellow, new 3.5" vband clamp, 3.5" stainless 90deg bend, and a 3.5" 16" long Dynomax resonator. I'm gonna ditch the cat and put in place the resonator. This is more so because I might upgrade the turbo to an S366SXE (6673) 0.81 a/r vs the current S362SXE (6268) 1.00 a/r. I'm going to put the car on the lift today so hopefully I can have it done on Saturday after 3-5hrs of work.

 

OK, so maybe 3-5 hours is about 3x under estimated!

 

I should have it wrapped up tomorrow. I installed the muffler last so I now have to modify the midpipe to line up since it is slightly off, but not big deal.

 

Finished!

 

looking good man, curious to see how much more power it’s going to put down with no cat.

 

Very nice work, and clean welds. Loving the transition to clear the under braces. Could we get a video of it idling once it's back up and running?