Rand0b

Yes I know that I can control with boost by gear and that is my plan, but as mentioned in the scenario the 3076 is small enough to.build that power around 4 k but is limited to 500whp just not sure how a larger turbo power delivery would be

Agreed, that’s why I was asking on power delivery. If a 3076 is going to hit like a light switch 20psi ~4000rpm i would think a slightly bigger turbo that maybe would start spooling 3500 and then gradually lean into 20 psi around 5k would be better power delivery? just don’t kno what that turbo is

has the same internals except the 300zx 98 spec has stronger synchros, fork and redesigned gears. This is the go to for the 300zx people making ~700whp

Rb bellhousing on z32 jdm trans has been reliable to ~700whp

I’m also confused because people are saying the RBs don’t build boost well but I see everyone recommending 1.0x for turbine a/r

Rb will be in a z32 chassis and hood clearance will be tight that’s why a ffp is needed, gotta have a top mount manifold to show off the turbo I will try my best to get a plazman top half but who knows if it will fit

I was looking at this turbo and the feature set is nice. just the bulkyness of the compressor housing / features isn’t clean for me. Yes I am leaning a bit more for looks in this case

That’s what I was thinking I may need to rollback a bit. I plan on having a good tire with some meat on back ~275 /40

Hi all was looking for some real world input on a badass street rb25. the biggest thing is that I have never owned an RB25 before. Will be rb25 in z32 will have supporting mods needed FFP, id1300 , built bottom end Will I NEED cams? I don’t think so since it’s not a full effort track dedicated setup. I think they would assist but not 100% necessary. wanting drop in with no head clearancing needed was thinking tomei poncams IF needed I have been Looking at rb25 and rb26 dyno sheets to see what a good balance is for HP goals vs turbo spool. Would love to hit 6-7XX number on the dyno. using race fuel /e85 But willing to be realistic on dyno number. I looking at 25 dyno graphs gives idea on power/spool However does not give what drivability is like. And I know pump gas power would be lower power overall I was thinking of a turbo that would be almost maxed out on the dyno on e85 so then it would still be a good turbo for street if not on e85, (e30,e50, ect) so i don’t know what size turbo would make a RB laggy or not street friendly. I know there is a tradeoff in spool vs power, but For a street RB with spool /response 20psi by ~4k GREAT!! 20psi by ~4.5k Good 20psi by ~5k ok… 20psi by ~5.5k Laggy So I guess from you experience what would your comments be? Are my dyno power goals out of reach for a GREAT!! – Good street car? Would you adjust the psi vs rpm category for the GREAT!! Good ok Laggy?? Everyone seems to like the Precision 6262 and people have made some good power on e85 in the rb25 dyno / precision thread. I seen a lot of people praise the power / response for the 6262 SilverECR33 had a 6262 BB and made 500hp on 24psi e85 so a 6062 gen2 should be able to make more with better response R33ryan had a 6062 BB and made 710 at 29psi e85 I have heard a lot of good things from the Hypergear turbos also ATR43SS3-Pro T3x 900HP made 455rwkws @ 22psi, E85 fuel, Rb25det Maybe the 6266 but it needs to have a two scroll manifold but then have read others say it’s to big a turbo I think these fall right in the ballpark of what I would need for a Badass Street Car and get close to my Power goal Thinking the 6062 , or the ATR43SS3-PRO? thanks !

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

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 I just came across your thread below and looked interesting. i know the SX-E is older technology but for G Series being over double the price with the RB30/25 hybrid running the s362 i would think for my goals on RB25 i would need a step or 2 higher and with the extra cash saved i could get some drop in cams what would your input be on a S366 for my setup? or comparable With this not being a Full Effort Race/Track setup i think this may be another contender

My choice was G30-900 or G35-900 not the g30-770 While the G30-770 may out perform the G30-900 it would not have the same HP potential With a Stock block w/bolt ons Street car EVERYONEs choice seems to be the 3076 for ~4-500whp and retains great spool / drive ability So that's why i was thinking G30-900 just to get a bit more power potential but what factor would cause one to move to the G35-900? i know it would have a shift in power band and spool just have not seen to many RBs running these G series turbos for comparisons I am building this for a Great Street car I have a Built Bottom end, FFP, Ported head and Stock cams and T3 for my Turbo Manifold if i see anything 6XX or maybe even 7XX on the dyno i would be happy IF the G30-900 acts like 3076 but can put down more power i think thats my go to. But if the G30-900 is to 'small' and hits to quick i could possibly adjust Boost curve in the tune Or when would the G35-900 be better suited

Can you clarify on this some more? Are you saying the Name vs HP rating that all the turbos should be bumped up to the next class? G35 should be gtx40XX due to g35 power output? the G series is more efficient so at least the g30-770 = gtx3076 why wouldn't the g35-900 = gtx3582? I am on the fence of g30-900 vs g35-900 Built RB25 stock cams 6-700whp goal pump 93 Street car willing to sacrifice some spool time (~500rpm) If the power delivery is better /linear for g35