Borg Warner S360SX vs S362SX-E testing on a drunk RB30DET

[Lithium]

Hi all, things are mostly dead in here but I figured its still worth recording this somewhere as people here or out in the world who google stuff may find some of this interesting as there seems to be a bit of interest in these turbos from a value for money stand point - but a fair bit of conflicting info... so I thought I'd add something which *I* view as kinda credible info, take it as you will

As a bit of background, one of my best mates  @Looney_Head has been chipping away at his build in his garage over the years - he has done most of it himself or with help from mates... doing things on a relative budget, but "properly".    Probably unsurprisingly here he picked my brain for turbo choices, and around ten years ago the build was going to be a stock/reconditioned RB30 with an R32 RB25 head so the target was around 370kw @ hubs on BP98 so I suggested a Borg Warner S360SX with .91a/r hotside as it could be had for NZ$900 at the time, should offer decent response vs power vs reliability and being a large frame T4 divided turbo there should be an easy upgrade path with minimal changes if he decided to in future.   Turns out that was a good plan as feature creep resulted in the build having a forged RB30 bottom end and an R33 RB25 head with some Tomei 256 cams and a mild port job. 
        
We knew that the turbo was going to now be well out of it's depth but being that the car is an R32 GTS-t it probably was likely to end up still being a bit of a weapon so when it was already ready we decided to tune it up and find any bugs etc and he could have fun with it for a while.  On the dyno as I progressively increase BCS duty cycle it started becoming clear that it was hitting a brick wall pretty much bang on where I expected it to - basically being unkeen to support more than 18-20psi boost at 7000rpm, so we ended up stopping with boost peaking at 23psi and bleeding back to around 19psi and making a very fat 447kw @ hubs on E70ish.

See the mighty S360SX dyno plot complete with choke as soon as it hits 600hp:

That proved to be a very very fun street package, but the opportunity came up to get our hands on an upgrade for a good price so after much umming and ahhing we settled on an S362SX-E (aka S361SX-E, aka S300SX-E 8376, aka S300SX-E 61/68 depending on whose nomclementure you subscribe to).

The process of chosing that was actually pretty challenging due to the conflicting info on the net which is part of the reason for me starting this thread - to share the process and reasoning and then the interim results, hopefully to clear things up a bit.   Firstly, our hopes were to free up the flow up top with minimal cost to response.   

So, questions you may find hard to answer or generally look misleading when looking at these:

1) The S362SX-E with the 76mm turbine wheel (there is an option to use the 80mm wheel) can go directly into an exhaust housing which fits the the S360SX turbine wheel.  They are an identical 76mm inducer/68mm exducer profile.

2) Despite being exactly the same size the SX-E turbine wheel is DIFFERENT to the SX wheel, the aero is very obviously different.   The SX has "flat tips" while the new SX-E has cupped tips - I'll attach pics, but its pretty obvious how the exhaust gas will react with the wheel as it "hits" and flows through the blades will change.   See below:

(S360SX turbine left, S362SX-E turbine right):

3) The "76mm .91a/r" turbine flow map on Matchbot relates to the SX-E wheel.  I had to work this out anecdotally, but it became clear that the S300SX flat-tip wheel is a bit of a nugget flow wise and in combination with the pretty average flow of the 60/83mm S360 compressor results in very high EMAP if you want to make >500whp.   Due to that, and the internet being mainly convinced that the S300SX and S300SX-E turbines are the same people often go for  larger a/r turbine housings than they need when going 76mm SX-E turbos.   The 76mm .91a/r hotside combo on an S300SX-E flow the same as a 1.05a/r 74mm EFR turbine.   It has been proven to support 900whp (US dynos)/ near 600kw (Oz dynos) on the right setup.      People are often oversizing the hotsides on Borg Warner Airwerks turbos and living with more lag than they need, imho.

So, after my research and deciding that there was a bit of misinformation out there - I decided that going for the 76mm turbine wheel in the SAME .91a/r housing we'd be running should make for minimal sacrifice to response but not actually choke the turbo despite the fact that we had seen massive signs of choke on the old turbo in the same housing (VE was dropping off increasingly badly in the 220kpa and 240+kpa rows in the engine efficiency table - and boost control duty cycle had a major dogleg after 5000rpm to target 240kpa MAP).

In terms of compressor wheel, the "S362SX-E" actually has a 61.4mm inducer and 83mm exducer, so identical outer size to the S360SX (or 8375) that was being replaced but only 1.5mm bigger inducer.   This wee thing is a bit of a gem on paper, the loose info on the net would suggest that the 63mm and 64.5mm inducer variations are big steps up but after close investigation I found that actually - the compressor maps for those turbos "cut off" at around 54-56% while the 61.4mm one only runs to 58-60%.   If you compare these maps at "efficiency for efficiency" then the 63mm BARELY pips the 61.4mm wheel, and the 64.5 has a max of 6% more flow in the 2.2-2.7 pressure ratio range that your focus would be on a decent RB.     When you consider that the 63 and 64.5mm wheels are both 87mm exducer, there is no way there is not going to be a significant impact to spool or transient response.    The big flow advantages on those bigger inducers are at pressure ratios of 3+, which is not relevant - and the 66+mm inducer is just not relevant to our interests as we weren't looking for huge power.   

Here is the old and the new turbos: (SX-E left, SX right)

 

I actually overlayed the ol' faithful EFR8374 compressor map (in red) onto the S362SX-E compressor map and it becomes obvious the SX-E is a good thing, having a better surge line but also providing equal or better compressor efficiency at almost every relevant flow/pressure point on the compressor map.   So, decision made, turbo install and off we go for some dyno hilarity!   

        
At low boost it was like the turbo was identical, it was basically tracking the exact same boost curve and making the same power at ~10psi - no shocks there.   What got interesting however is that as I started targetting higher and higher boost levels, the BCS duty cycle could stay relatively "flat" whereas with the S360SX I was needing to bump duty more and more from 5000rpm up - and I also ended up basically copying the VE numbers from 200kpa row and pasting it to every row above that and having lambdas hit target perfectly - while I needed to roll them back with the S360SX. 

Naturally, this was reflected in power numbers as well.    Things were starting to get fun!  When I targetted the 240kpa MAP level when there S360SX was done we were all excited and looking forward to seeing what happened things got more dumb than we hoped - the Link did a fuel pressure cut at 6500rpm, and looking at the logs there was indeed a fuel pressure drop starting to set in   We ummed and ahhed about it and wondered if the surge tank was a bit too small so tried increasing the ramp rate to do a 6s sweep instead of a 9s sweep but alas no, protection kicked in at exactly 6500rpm   We tried bumping base fuel pressure to see what would happen and it did allow is to complete a base run at 240kpa (20ish psi boost) and still no signs of dropping off in turbo flow but alas fuel pressure was still dropping.   VERY annoying but we had to call it a day and we are looking the fuel delivery issue for now.    

Nonetheless, 466kw on 1.4bar with power climbing to redline while making 300kw before 4000rpm was very encouraging.   We did do a "controlled" test run at 1.6bar to see what fuel pressure and turbo flow would do etc as dyno time is hard to get so we wanted to be sure that everything else would keep up with more and she is STILL eating it up, hits 1.5bar by 3700rpm on a 9s ramp and we saw a peak of 489kw with SOFT timing so I am very confident that we could have walked past 500kw if we hadn't run into fuel delivery woes!     

Firstly, shot from the link during a 9s sweep (as I forgot to get a pic of the boost curve from the dyno haha)

And the dyno plot....

Red dotted line: Old S360SX-E at 1.4bar bleeding back (same BCS duty cycle as the SX-E runs here) a 9s sweep

Solid red line: S362SX-E at 1.4bar on a 9s sweep with fuel cut

Solid green line: S362SX-E on a 6s sweep with fuel cut

Solid blue line: S362SX-E on a full 6s sweep 

There was no specific tuning done with the S362SXE at this boost level beyond targetting boost, timing has not been fully optimised at this boost with this turbo.

Anyway, I've attached some pics to go with the long story that anyone who knows me will know this is what they were in for when I posted.   Thought there might be some useful stuff for anyone who has been curious about these things, but either way this kind of thing is handy for our own records to look back on   Feel free to ask questions or offer input or whatever, in regards the fuel pressure thing we are not looking for input on that thanks, please keep the conversation on topic... we have stuff to do there - I've just not shared everything to keep it relevant to turbos.
 

Cheers all!

Edited November 17, 2019 by Lithium

[Looney_Head]

Excellent write up Dan, and yeah captures the day.

 

Attached is the video of the last run we did

[Lithium]

Chur - also, link to a build thread for more details on the build: 

 

 

[mitchum]

I had an S369SXE on my 26/30 the emap suffered horribly, be interesting to see it on this setup here is a datalog of mine

 

 

[Lithium]

3 hours ago, mitchum said:

I had an S369SXE on my 26/30 the emap suffered horribly, be interesting to see it on this setup here is a datalog of mine

Wow, yeah that is pretty bad.  I've heard mixed things about the S369SX-E, and Matchbot has no data on the 80mm turbine so I have no idea what to expect... if this is how you would expect it to be or if there is something else going on to inflate it so much, definitely one of those things where turbine speed would work hand in hand to make it clear whether that is definitely "normal" or if there is something compromising the setup.

What kind of power was it making, and have you changed now?  I wish I had more data on this, again it's pretty clear it has dropped a crapload of EMAP but it's still not clear where it actually is - I don't doubt it's not magically low or anything... just at an acceptable level compared to previously.

[Dale FZ1]

6 hours ago, mitchum said:

I had an S369SXE on my 26/30 the emap suffered horribly, be interesting to see it on this setup here is a datalog of mine

What housing was on your S369SXE?

[mitchum]

I was logging shaft speed which was just over 130k RPM 

Divided 1.0 T4 turbine housing too BTW

It made just over 800whp on 27psi and i couldnt get anymore boost out of it which isnt suprising being shaft speed was so high and emap thru the roof

Im assuming it likely would have made closer to 900whp+ if the EMAP wasnt so high. i was going to go to larger turbine housing but decieded to opt for the new G42-1200 unit from Garrett

With new turbo and a 1.15 turbine housing the EMAP now, on 28psi of boost is around 34psi. i am now dropping fuel pressure alot and am currently out of injector because of it. so looks to be making some more steam!

[Lithium]

19 minutes ago, mitchum said:

I was logging shaft speed which was just over 130k RPM 

Divided 1.0 T4 turbine housing too BTW

It made just over 800whp on 27psi and i couldnt get anymore boost out of it which isnt suprising being shaft speed was so high and emap thru the roof

Im assuming it likely would have made closer to 900whp+ if the EMAP wasnt so high. i was going to go to larger turbine housing but decieded to opt for the new G42-1200 unit from Garrett

OK that is what I wondered - the old "way off the map" trick is a prime cause for soaring EMAP.   The "choke line" from Borg Warner is around 117,000rpm for the S369SX-E - as you start drifting further off from there compressor efficiency will go ballistic as the wheels need to spin way harder to try and move any more air, so the wastegate has to close to try and keep boost going in and you just get raising EMAP and it tries to drive the compressor to get air it really isn't meant to shift.

Whether all that air was getting to the engine or not you were WAY off the compressor map, so trying to reduce EMAP by trying bigger exhaust housings etc would have been band aids to the issue.  Don't suppose the airflow model you were using gave an estimate of the airflow it reckoned the engine was getting?  Wonder if there is a chance there was an airleak or something, or does that power figure match up with 90+lb/min of airflow on that dyno?

[mitchum]

it was boost leak tested, and emap is thru the roof even on lower boost levels. combined with this CNC ported head and cams it just flows, it made 665whp on only 16psi which is almost 100whp higher then previous combo same turbo.. Car trapped 142mph at 680whp weighing 3200lbs, Dynojet 224x is the dyno its been on. 

[Lithium]

1 hour ago, mitchum said:

it was boost leak tested, and emap is thru the roof even on lower boost levels. combined with this CNC ported head and cams it just flows, it made 665whp on only 16psi which is almost 100whp higher then previous combo same turbo.. Car trapped 142mph at 680whp weighing 3200lbs, Dynojet 224x is the dyno its been on. 

It had a 6870 on it previously, from memory?

[mitchum]

I did have a 6870 on it for some time, but after multiple smoking issues with Precision i opted for something different. The S369 was also on both setups. Never a smoking issue with the Borg either!

 

Now im currently waiting on a new manifold to show up with better gate priority. and will be retuning with the new G42 in the coming months.

[Lithium]

4 hours ago, mitchum said:

I did have a 6870 on it for some time, but after multiple smoking issues with Precision i opted for something different. The S369 was also on both setups. Never a smoking issue with the Borg either!

 

Now im currently waiting on a new manifold to show up with better gate priority. and will be retuning with the new G42 in the coming months.

Cheers for clarifying  How did the S369 and the 6870 compare aside from the Borg not smoking?

The G42 should be quite interesting, definitely a bit of a step up!

[Rand0b]

With Lithiums Example he was using a RB30/25 build with Cams for SXE360 on e85

And he made ~650whp

 

My build will be

Built Bottom end RB25

Ported Head

Stock Valve Train

FFP , T3 Turbo Manifold w/ EWG

BP 93  (Only 2 e85 stations in my STATE (not city, State) and not consistent ‘e85’)

 

On the Dyno would love to hit a number between 6-700whp On Race Fuel / E85

Looking for FUN Street Car

Great Drivability , Great Midrange , fine with Good/ok  Top end (actually being realistic here)

This is not dedicated Track / MAX Effort Race Car

 

I think with Lithums example being a RB30/25 with cams on the sxe362

I think I may need a slightly bigger SXE364 / 366 to compensate for the rb30/25 additional mods the has

Plus will be mostly be running BP93

What are the thoughts for this

The SXE are a great bang for the buck

but not sure If I should be thinking more ‘2020 era’ for something with better performance relatively close in budget  1-1.5k

I can see spending some extra $ to gain ~500rpm spool possibly but will the efficiency range be where I need it while street driving the car. the s362 is right on the money according to the map

 

Which has been proven for 900whp the SXE362 or EFR?

 

[Lithium]

Seeing as someone brought this discussion up, I thought I'd do a slight update.   It turned out that the initial fuel pressure drop off was partly due to a power supply issue to the fuel pump, so we had another crack on the dyno since this.

We were confident enough this time to run it at 20psi and at least put the extra timing that it was missing in at that power level, bearing in mind that we never actually tried putting it in last time due to the fuel delivery issues.  This time we were running just over 85% ethanol and hit almost bang on the same ~466kw @ hubs that we did last time on 20psi, possibly slightly more - so everything seemed healthy and I went about optimising the timing.   

We ended up JUST cracking 500kw on 20psi with timing full put into it, but found that fuel pressure was STILL a bit of an issue with this ethanol content - more likely at this point that the fuel pump was actually just tapped out.   This was a bit of a bummer, as last time we had run it up to 23psi of boost on lower ethanol percentage - so KNOW that the turbo still has more in it.  Either way, we've proven it to be comfortably capable of passing 500kw @ hubs with a decent power delivery on an RB30    I'm not sure if it's going to get wound up any further or not as the thing is making good power as it is, and with RWD it's an absolute menace even in 4th gear hahaha.

Here's a wee video of us playing silly buggers late last year when we hired the local drag strip, rolling 4th gear skids

 

[Looney_Head]

one day i will get more fuel pump and we will send that turbo. it would be a dyno only thing as like Lith said its a menace on the streets with 20psi. it will do rolling skids at 160kph on a 265 semi slick lol

 

and Rand0b, you have said lots of words, but to answer your question, the SX362SXE will not make 900whp, you will not get a 900whp turbo on an RB35 that will have good midrange. going to a S366 wouldn't be worth it from what i have seen. they are laggy and you would have a faster car with more power band

[Lithium]

On 22/04/2022 at 11:31 AM, Rand0b said:

RB30/25 build with Cams for SXE360 on e85 he made ~650whp

FFP , T3 Turbo Manifold w/ EWG

BP 93  (Only 2 e85 stations in my STATE (not city, State) and not consistent ‘e85’)

On the Dyno would love to hit a number between 6-700whp On Race Fuel / E85

Looking for FUN Street Car. Great Drivability , Great Midrange , fine with Good/ok  Top end (actually being realistic here)

I think I may need a slightly bigger SXE364 / 366 to compensate for the rb30/25 additional mods the has

but not sure If I should be thinking more ‘2020 era’ for something with better performance relatively close in budget  1-1.5k

Which has been proven for 900whp the SXE362 or EFR?

There is some pretty confused stuff in this so a bit to unpack, I'll try and be as helpful as possible on this as it feels like you have quite a bit to learn and could easily end up choosing something that REALLY doesn't suit what you want.   Don't rush out and buy something until you've done a bit more research/thinking about it, but I'll try my best to get us on the same page etc.

So to address your points: 

• RB30/25 build with Cams for SXE360 on e85 he made ~650whp 
  
  This is @Looney_Head's build, I just tuned it.   He started with the S360SX on E85 and that tapped out at 600hp.   The S362SXE (61.4mm inducer) we've seen over 650hp and could potentially stretch to 700hp on E85 depending on the setup and the dyno.
  
   
• FFP , T3 Turbo Manifold w/ EWG
  
  The Borg Warner turbos are best used with T4 twin scroll manifolds, I wouldn't use one if you are going T3 manifold.  More on this soon
  
   
• BP 93  (Only 2 e85 stations in my STATE (not city, State) and not consistent ‘e85’)
  
  So you're using flex fuel?   Hope you know that you'll have to drop your power targets for when it's on 93?
  
   
• Looking for FUN Street Car. Great Drivability , Great Midrange , fine with Good/ok  Top end (actually being realistic here)
  
  This is all open to interpretation of what you find driveable, but the S362SXE would be quite doughy on an RB25 - like potentially mid 4000rpm before full boost.  The S366 will be getting closer to 5000rpm, they are not things I'd call great for street use.   This range is great for 3litres, but smaller it depends on how much you mind it being a bit lazy under 4000rpm.
  
   
• I think I may need a slightly bigger SXE364 / 366 to compensate for the rb30/25 additional mods the has
  
  It doesn't work this way, if anything you often need a bigger turbo for similar power on a bigger engine.   Any power you can make on an S362SXE on an RB30, you'll make happily with an RB25.   What I should add here is that you really should be looking at cams and definitely valve springs if you want to go much past 500whp.
   
• Which has been proven for 900whp the SXE362 or EFR?
  
  There is no way you're going to make 900whp with an S362SXE, why are we talking about 900whp?  You said 600-700hp max earlier   But people *have* tapped 900hp on hub and some roller dynos with an EFR8474 but really you'd be going an EFR9280 or an S369SX-E if you wanted that kind of power... and they WON'T be a fun street setup on an RB25 unless you don't mind waiting until 5000 before it gets fully spicy.
  
   
• but not sure If I should be thinking more ‘2020 era’ for something with better performance relatively close in budget  1-1.5k
  
  I'd consider a Garrett G-series copy from Pulsar turbos, they perform well if you don't mind the ethical grey area of running a turbo which is cheap because they've let someone else do the R&D.
  
  Something like this will get you over 600whp on E85 and over 500whp on 93 while still having reasonable response and a good price, and it conveniently comes with a T3 open housing option: https://www.pulsarturbo.com/product/pulsar-5855g-aka-g30-770-dual-ball-bearing-turbo/

Edited April 22, 2022 by Lithium

[Rand0b]

There is some pretty confused stuff in this so a bit to unpack, I'll try and be as helpful as possible on this as it feels like you have quite a bit to learn and could easily end up choosing something that REALLY doesn't suit what you want.   Don't rush out and buy something until you've done a bit more research/thinking about it, but I'll try my best to get us on the same page etc.

this is my first RB build so do not know these motors, but exactly why i am looking for input on turbo selection. the number one thing i came across is that RBs breathe and not to run .63 a/r Minimum is .82

So to address your points: 

• RB30/25 build with Cams for SXE360 on e85 he made ~650whp 
  
  This is @Looney_Head's build, I just tuned it.   He started with the S360SX on E85 and that tapped out at 600hp.   The S362SXE (61.4mm inducer) we've seen over 650hp and could potentially stretch to 700hp on E85 depending on the setup and the dyno.
• agreed and understood no questions on that  just using this as a baseline for my comparison
  
   
• FFP , T3 Turbo Manifold w/ EWG
  
  The Borg Warner turbos are best used with T4 twin scroll manifolds, I wouldn't use one if you are going T3 manifold.  More on this soon
  understood you are referencing t4 twin scroll manifold to help with spool on the journal bearing turbo
   
• BP 93  (Only 2 e85 stations in my STATE (not city, State) and not consistent ‘e85’)
  
  So you're using flex fuel?   Hope you know that you'll have to drop your power targets for when it's on 93?
  BP is a gas company that has quality gas in the States. this is 93 octane ( highest at pump in US) i dont mind having to always add octane booster when filling up if needed
• Yes target goals are understood as thats why i said 6-700whp on Dyno with racefuel / e85
• i know overall power would be less on 93
   
• Looking for FUN Street Car. Great Drivability , Great Midrange , fine with Good/ok  Top end (actually being realistic here)
  
  This is all open to interpretation of what you find driveable, but the S362SXE would be quite doughy on an RB25 - like potentially mid 4000rpm before full boost.  The S366 will be getting closer to 5000rpm, they are not things I'd call great for street use.   This range is great for 3litres, but smaller it depends on how much you mind it being a bit lazy under 4000rpm.
  gotcha, i know that the RB motors like to breathe so i had thought that a sxe362 would be an good choice and 366 a Ok choice in this sense
• AGP turbos makes a hybrid Borg SXE2/300 SXE261
• i found this last night and though it may be a better option from the 362 due to turbine wheel size

•  Compressor Specs:
  - 61.44mm inducer 83.47mm exducer FMW Forged Milled Wheel (Billet)

  Turbine Specs:

• -61mm exducer, 70mm inducer turbine wheel
  -T3 Open Scroll turbine housings available: .63, .82, 1.06 A/R with 3" V band outlet

• https://agpturbo.com/borg-warner-agp-s261-sx-e-61-61/

• I think I may need a slightly bigger SXE364 / 366 to compensate for the rb30/25 additional mods the has
  
  It doesn't work this way, if anything you often need a bigger turbo for similar power on a bigger engine.   Any power you can make on an S362SXE on an RB30, you'll make happily with an RB25.   What I should add here is that you really should be looking at cams and definitely valve springs if you want to go much past 500whp.
   
• that rb30 combo has more cubes to push the 362 at low boost,
• so with my RB25 being as a street car it would  be living low / mid boost most of the time.  to make the same power the rb30 does with the 362 the rb25 would need to be at a higher rpm/ at a higher boost level so for the rb25 to make somewhat similar power at same low/mid boost i would need a bigger compressor to push more air no? yes i know it would suffer difference in spool time but that is why i am looking at the last statement on this post

• Which has been proven for 900whp the SXE362 or EFR?
  
  There is no way you're going to make 900whp with an S362SXE, why are we talking about 900whp?  You said 600-700hp max earlier   But people *have* tapped 900hp on hub and some roller dynos with an EFR8474 but really you'd be going an EFR9280 or an S369SX-E if you wanted that kind of power... and they WON'T be a fun street setup on an RB25 unless you don't mind waiting until 5000 before it gets fully spicy.
•  i am going off your statement under the pics of the 2 turbine housings
• 'It has been proven to support 900whp (US dynos)/ near 600kw (Oz dynos) on the right setup.      People are often oversizing the hotsides on Borg Warner Airwerks turbos and living with more lag than they need, imho.'
• so i was not sure what turbo you were referencing , cuz i would have scaled down my selection of borg turbo

 

• but not sure If I should be thinking more ‘2020 era’ for something with better performance relatively close in budget  1-1.5k
  
  I'd consider a Garrett G-series copy from Pulsar turbos, they perform well if you don't mind the ethical grey area of running a turbo which is cheap because they've let someone else do the R&D.
  
  Something like this will get you over 600whp on E85 and over 500whp on 93 while still having reasonable response and a good price, and it conveniently comes with a T3 open housing option: https://www.pulsarturbo.com/product/pulsar-5855g-aka-g30-770-dual-ball-bearing-turbo/
• i was thinking of this turbo but for the overall price i could get a borg that has proven history and reliability but not sure which one to get
• from my research the gtx3076 is the go to for ~500whp and great response 
• but i am looking for some comparable turbos between the 3076 and 3582  to  as the 3076 would be jsut to small for my goals and i have read a few  showing that the 3582 is to big for a stock rb25 and not street friendly
• Mind you the only reason i have a built bottom end is because i came across a good deal on one and im not building the head as from research/FB group posts it shows stock head / cams are ok for 7-800whp so with my goal of making 6-700 on the DYNO i think they would live fine for street use

[Lithium]

On 23/04/2022 at 3:40 AM, Rand0b said:

 

• It doesn't work this way, if anything you often need a bigger turbo for similar power on a bigger engine.   Any power you can make on an S362SXE on an RB30, you'll make happily with an RB25.   What I should add here is that you really should be looking at cams and definitely valve springs if you want to go much past 500whp.
   
• that rb30 combo has more cubes to push the 362 at low boost,
• so with my RB25 being as a street car it would  be living low / mid boost most of the time.  to make the same power the rb30 does with the 362 the rb25 would need to be at a higher rpm/ at a higher boost level so for the rb25 to make somewhat similar power at same low/mid boost i would need a bigger compressor to push more air no? yes i know it would suffer difference in spool time but that is why i am looking at the last statement on this post

• Which has been proven for 900whp the SXE362 or EFR?
  
  There is no way you're going to make 900whp with an S362SXE, why are we talking about 900whp?  You said 600-700hp max earlier   But people *have* tapped 900hp on hub and some roller dynos with an EFR8474 but really you'd be going an EFR9280 or an S369SX-E if you wanted that kind of power... and they WON'T be a fun street setup on an RB25 unless you don't mind waiting until 5000 before it gets fully spicy.
•  i am going off your statement under the pics of the 2 turbine housings
• 'It has been proven to support 900whp (US dynos)/ near 600kw (Oz dynos) on the right setup.      People are often oversizing the hotsides on Borg Warner Airwerks turbos and living with more lag than they need, imho.'
• so i was not sure what turbo you were referencing , cuz i would have scaled down my selection of borg turbo

 

• but not sure If I should be thinking more ‘2020 era’ for something with better performance relatively close in budget  1-1.5k
  
  I'd consider a Garrett G-series copy from Pulsar turbos, they perform well if you don't mind the ethical grey area of running a turbo which is cheap because they've let someone else do the R&D.
  
  Something like this will get you over 600whp on E85 and over 500whp on 93 while still having reasonable response and a good price, and it conveniently comes with a T3 open housing option: https://www.pulsarturbo.com/product/pulsar-5855g-aka-g30-770-dual-ball-bearing-turbo/
• i was thinking of this turbo but for the overall price i could get a borg that has proven history and reliability but not sure which one to get
• from my research the gtx3076 is the go to for ~500whp and great response 
• but i am looking for some comparable turbos between the 3076 and 3582  to  as the 3076 would be jsut to small for my goals and i have read a few  showing that the 3582 is to big for a stock rb25 and not street friendly
• Mind you the only reason i have a built bottom end is because i came across a good deal on one and im not building the head as from research/FB group posts it shows stock head / cams are ok for 7-800whp so with my goal of making 6-700 on the DYNO i think they would live fine for street use

•  so with my RB25 being as a street car it would  be living low / mid boost most of the time.  to make the same power the rb30 does with the 362 the rb25 would need to be at a higher rpm/ at a higher boost level so for the rb25 to make somewhat similar power at same low/mid boost i would need a bigger compressor to push more air no? 
  
  Are you saying you think the turbo needs to push more air to make the same power on a smaller engine?  If so, no - it doesn't.  The amount of power you make has a very close correlation to how much air the turbo moves.  The only reason you may need a different sized turbo is if the compressor (or turbine) will be inefficient in the operating area it would work with on a different engine.  The RB25 and RB25/30 are similar enough that this will not be a thing.  All going to a bigger compressor (or bigger compressor and turbine) is going to do is increase lag - ESPECIALLY if you have stock cams.
   
• 'It has been proven to support 900whp (US dynos)/ near 600kw (Oz dynos) on the right setup.      People are often oversizing the hotsides on Borg Warner Airwerks turbos and living with more lag than they need, imho.
  
  This comment was purely about the hotside.  The 61mm compressor wheel will not support that by a long shot.  The 64mm one won't either - on an RB the 64mm has bugger all advantage over the 61.4mm actually, especially on an engine which doesn't run >30psi.
  
   
• but i am looking for some comparable turbos between the 3076 and 3582  to  as the 3076 would be jsut to small for my goals and i have read a few  showing that the 3582 is to big for a stock rb25 and not street friendly
  
  This is pretty much why I suggested the G30 770.   It's a slightly smaller turbo than the GTX3076R (same size turbine, smaller compressor) but flows similar to a GT3582R.   It basically means you end up with something with a similar boost threshold to a GTX3076R, better transient response and able to make GT3582R power numbers.

[GTSBoy]

On 4/25/2022 at 4:00 PM, Lithium said:

he only reason you may need a different sized turbo is if the compressor (or turbine) will be inefficient in the operating area it would work with on a different engine.  The RB25 and RB25/30 are similar enough that this will not be a thing. 

The key difference here is that the smaller engine will require a higher pressure ratio (more boost) to flow the same amount of air through the engine - hence Lithium's point about there possibly being a need for a different size turbo if that higher boost would put you up against the surge line or way off the efficiency island cf the larger engine.

[Rand0b]

On 4/25/2022 at 4:00 AM, Lithium said:

•  so with my RB25 being as a street car it would  be living low / mid boost most of the time.  to make the same power the rb30 does with the 362 the rb25 would need to be at a higher rpm/ at a higher boost level so for the rb25 to make somewhat similar power at same low/mid boost i would need a bigger compressor to push more air no? 
  
  Are you saying you think the turbo needs to push more air to make the same power on a smaller engine?  If so, no - it doesn't.  The amount of power you make has a very close correlation to how much air the turbo moves.  The only reason you may need a different sized turbo is if the compressor (or turbine) will be inefficient in the operating area it would work with on a different engine.  The RB25 and RB25/30 are similar enough that this will not be a thing.  All going to a bigger compressor (or bigger compressor and turbine) is going to do is increase lag - ESPECIALLY if you have stock cams.
•  
• This basically answers my question then. I researched and everyone was saying  RB30 swap it had better  transient/low speed response,  builds boost easier, better throttle response. I did not thing that they were close enough for that to not be a factor. 

 

• 'It has been proven to support 900whp (US dynos)/ near 600kw (Oz dynos) on the right setup.      People are often oversizing the hotsides on Borg Warner Airwerks turbos and living with more lag than they need, imho.
  
  This comment was purely about the hotside.  The 61mm compressor wheel will not support that by a long shot.  The 64mm one won't either - on an RB the 64mm has bugger all advantage over the 61.4mm actually, especially on an engine which doesn't run >30psi.
  
   
• but i am looking for some comparable turbos between the 3076 and 3582  to  as the 3076 would be jsut to small for my goals and i have read a few  showing that the 3582 is to big for a stock rb25 and not street friendly
  
  This is pretty much why I suggested the G30 770.   It's a slightly smaller turbo than the GTX3076R (same size turbine, smaller compressor) but flows similar to a GT3582R.   It basically means you end up with something with a similar boost threshold to a GTX3076R, better transient response and able to make GT3582R power numbers.

yea i think G30-770 or G30-900 will be my go to choice.

I have done some research and people have been saying Pulsar has been around for a while and the falcon guys praise their stuff, but i cannot find any historical reviews showing Pulsars track record ( nothing before 2020) for reviews or dyno graphs ect

Since you recommended it do you have any thoughts , experience, or resources for historical reviews?