Jump to content
SAU Community

Recommended Posts

Hi Guys..

Just wondering what u guys think? I am gettin a 2530 Hi Flow spec Turbo soon but the one i'm gettin is

in a .86 T28 turbine housing in a .60 comp so identical to 2530 except its .64 turbine as .64 will seem too

small for RB25DET.

Will i get slightly more power @ .86? I'm thinking of running 17-18psi so get about 230rwkw and max out the

the stock injectors and AFM unless i make more n therefore get bigger AFM n Injectors.

I have all the basic supporting mods like Power FC, FMIC, 3" Turbo Back, Bosch910 pump, Splitfires, HKS EVC, Apexi Pod

with Metal Intake Pipe. Just want to know if i should get anything else like bigger AFM, injecorts or possibly step 1

cams b4 i go 4 the Tune?

Cheers

Ces

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/
Share on other sites

  • Replies 42
  • Created
  • Last Reply

Top Posters In This Topic

The way I look at things is that an exhaust AR indicates the turbos power band. Basically speaking the .86 will come on later and stay on longer, while obviously with a few extra RPMs you should also see a slightly higher output up top. You should also note you will lose some mid range punch.

Being built off a HKS 2530 spec results are readily available, and the .64 is not too restrictive for an RB25 no. People are using .63 housings on GT30 and GT35 based setups to great results. In saying so, if you look into the 2530 results and like what you see, you should stick to the 2530s original housing size, if you feel that it comes on uselessly early and dies off too quick (which it doesnt) and foresee a USEABLE advantage to shifting the power band up then opt for the .86.

I would consider a .86 housing in a circumstance where the turbo is maxing out the rear housing too early. For example, I am a fan of the 2871 (GTRS) but can see constraints in how much boost can be run efficiently, now the curve on a 2871 is excellent enough as it is so I can justify running a .86 on it to get a little more flow out of the back end, seeing as I believe the compressor has more flow in it too. In saying so, I still think the .64 one HKS sells it with would be better, I just thought of this theory to try and squeeze the most out of the garrett equivilent. The garrett has no surge slots and the HKS housings are possibly not garrett standard issue items SO the .86 idea was a way for it to be run a little harder in exchange for some low down torque, which was probably only a loss up till 3500 ish and it would balance back out.

Have a good think about it and compare results, also try to consider how much boost people run already... 17-18psi seems a normal number for a 2530 so maybe the .64 is the best way to go especially if you dont want to rev much beyond 7000. Remember the stock turbo is a .48 AR on a 33.

Its not the motor maxing out the housing its the front size of the turbo maxing out the rear side with the motors ability to eat air as a variable. Thats why highflows in stock housings still work and make excellent power, because the rear wheel is big enough to let gas thru that doesnt choke it.

GL and keep us updated with your results.

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5120737
Share on other sites

Firstly only HKS made a proper GT28 turbine housing in T3 flange , the Garrett ones have the smaller T25/28 mounting flange .

A real T3 flanged 0.86 A/R turbine housing would be a godsend because with much over 2 liters you need it to get the exhaust out .

I don't give a rats what anyone else thinks , I proved that the 0.86 sized T28 flanged turbine housing can and has been used with good results even on a 2L four provided the head is good - FJ20's are . Mine made positive pressure with one on a GT2860RS turbo at 15-1600 revs so an RB25 would do it easier with 25% greater capacity .

The GT2530 and GT2860RS are very nearly the same thing , only the minor differences in the compressor wheel make them different . Same turbine and can use the same housings though again that minor difference in compressor wheel profile .

One of the past Turbo Production Engineers at Garrett in the US , RC , once said that he could not understand why HKS didn't do a 0.86 housing for the 2530 because that size works really well on the GT2860RS .

A .

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5120795
Share on other sites

Thanks 4 da Response Guys.. really helpfull Information :-)

Already have the 0.86 A/R version on the way n waiting 4 it to arrive then just gotta hunt around for a z32 AFM & 550cc injectors.

Then i'll go in 4 a Tune n c how it goes..

I'll keep u updated.

I"ll b a Happy with a Response Torque Monster which is what i'm Aiming for :-)

Ces

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5120879
Share on other sites

Thanks 4 da Response Guys.. really helpfull Information :-)

Already have the 0.86 A/R version on the way n waiting 4 it to arrive then just gotta hunt around for a z32 AFM & 550cc injectors.

Then i'll go in 4 a Tune n c how it goes..

I'll keep u updated.

I"ll b a Happy with a Response Torque Monster which is what i'm Aiming for :-)

Ces

You will need a fuel pump too if you dont already have one, no doubt we will see each other in threads selling Z32 afm's and 044/040 fuel pumps :thumbsup:

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5120959
Share on other sites

id like to see a 0.86 rear 2530, that would be pretty funky

is the main issue with the smaller compressor style turbos (2530, gt-ss (in single form) etc) is that the rear is usually tiny and it strangles exhaust?

i know this sounds whack and goes against everything we agree on but what about a larger GTR twin in single form on an inline 6?

roy (troy) has a twin from a td06 GTR kit in single form on his rb20 and it is bulletproof (with ext manifold, gate etc).

like using a 2835 pro R from a GTR twin kit as they are external gate too ? vs the normal 2835 pro S which is single, but in internal gate

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5121235
Share on other sites

  • 2 months later...

Paul I would expect a 0.86 housing to give similar results on a 2530 or a GT2860RS provided they use the same compressor housing .

I think it goes without saying that twin TD06's or GT2835's is a lot of turbo in twin form on a std capacity RB26 and I wouldn't think would boost too well down low .

I look at turbine housing A/R size a a means of tuning turbo/ine speed around engine speed - effectively where you want the thing to boost relative to engine speed .

A .

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5236902
Share on other sites

According to Stao if i wanted to the boost to hold all the way to 15psi towards redline i would have to run an external gate or play around with the wastegate preload which i assume is the the nut and rod connected up to the actuator to the turbo.. so if i could get it to hold to 15psi towards redline it should net around 330-340RWHP??

What if i run a Front-Screamer pipe??? will that hold the boost towards redline?

What do guys reckon of the result?

Edited by Black_CSR
Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5236949
Share on other sites

If you have a good dump and front pipe on it already, a screamer pipe wont do anything other than put a big hole in your wallet when the cops catch on.

If you look at results for these turbos when done by HKS, you will see they usually dont have an issue holding boost to redline. Same can be seen on HKS 2835 vs a garrett 3071 equivalent.

I feel the issue is more so the housing design rather than the need for an external gate. I personally dont think the addition of an external gate is necessary or beneficial.

AFAIK Stao is using T25 housings and modifying them for a T3 footprint. Perhaps the design needs some improvement to adopt the altered flow dynamics. Hopefully Stao and some other gurus can step in to provide further insight.

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5238177
Share on other sites

If you look at results for these turbos when done by HKS, you will see they usually dont have an issue holding boost to redline.

I feel the issue is more so the housing design rather than the need for an external gate.

Exactly right.

If the true HKS 2530 can hold 20psi virtually until redline - and a copy cannot, then that is the COPY failing.

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5238195
Share on other sites

Exactly right.

If the true HKS 2530 can hold 20psi virtually until redline - and a copy cannot, then that is the COPY failing.

Common you are a mod sitting on front on PC reading dyno sheets every day. You know better then that.

You can not get HKS2530 to hold 20psi internally gated straight to 7000RPM. I haven't seen one that can hold 14psi to redline. I can possible engineer it to do that if I really want to, how ever you can not ever get one that can. So please give the correct correspondence.

This turbo was build and sold for evaluation purposes, which I was expecting around 220rwkws.

End result of 237rwkws, with plenty of torque. Its not a bad firgures compare to every one else who's running the 2530 units.

The other factor is this is pretty much the max of what this comp wheel is capable off. More boost can cause a negative impact on HP gain. My initial test running CA18det with GT2860RS CHRAs shown 225rwkws on 20psi and 197rwkws on 24psi, RB25det requires lower boost to reach those boundries

I'm taking neutral view for this result as I've managed better response and power with a newer prototype recently.

You can get it to hold 16psi straight with wastegate controller. I'm unsure what sort of power it can make, but I don't think it would make any thing more then 10kws.

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5238564
Share on other sites

Well for a turbo salesman/creator i'd expect better from you at times as well, but hey - Must be monday-itis in the air.

Either way I had RB20 in my head for some reason... I'd seen a few results holding till redline (17-18psi), so my bad... RB25 in this instance is being discussed.

Was from the Dyno sticky...

http://www.skylinesaustralia.com/forums/Rb...30#entry3498307

& another:

http://www.skylinesaustralia.com/forums/po...62-DSC00342.JPG

For references sake etc.

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5238688
Share on other sites

RB25det has lot higher exhaust manifold pressure. The less pressure there is the more boost you can comfortably control.

I don't believe it is possible to hold 20psi to redline with an internal gate on a HKS2530 or equivalent in Garrett patterned housings with RB25det. Unless that is in a uncontrolled/controlled creep.

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5238732
Share on other sites

2530 or 2535, the rear housing it too small, boost will drop off and will not hold anymore than 15psi or more boost till redline.

I'm with Stao... it's not a copy fail, I'm running a HKS 2535 and have exactly the same boost output, no matter how much gain is added or boost, it will simply not hold till redline due to the small ass housing. You can only force so much exhaust pressure into the rear housing to turn the turbine, after that you're just generating heat.

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5239318
Share on other sites

So once the maximum flow of the housing is reached, boost drops, and enlarging the wastegate will just drop it more I guess. Is there a gain to be had flowing more exhaust out an external gate if the housing is maxed?

So there is no point me buying your boost controller Johnny? :D

Damn, I was hoping that would solve my boost drop issue.

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5239400
Share on other sites

So once the maximum flow of the housing is reached, boost drops, and enlarging the wastegate will just drop it more I guess. Is there a gain to be had flowing more exhaust out an external gate if the housing is maxed?

So there is no point me buying your boost controller Johnny? :D

Damn, I was hoping that would solve my boost drop issue.

Using a good boost controller will give you better control of boost, will bring on boost earlier, and also elevate boost spikes, where bleed valves have no chance of controlling high levels of boost. Futhermore, with EBC you maybe able to hold the boost at your desired level for more of the RPM range.

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5239601
Share on other sites

i have a few of the new bolt on gt 3076 bolt kits in the 0.82 56t making more power and better response on less boost than half of the highflows we see. If i was you i would buy an off the shelf turbo, of all the highflows and so forth ive seen through the shop (about 20-25) none have matched off the shelf items for response and power @ reasonable boost levels.

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5239787
Share on other sites

i have a few of the new bolt on gt 3076 bolt kits in the 0.82 56t making more power and better response on less boost than half of the highflows we see. If i was you i would buy an off the shelf turbo, of all the highflows and so forth ive seen through the shop (about 20-25) none have matched off the shelf items for response and power @ reasonable boost levels.

How's this one Trent? PU MAX high flow Profile .63

And you need to start answering people's phone calls man. Ring you lots times for a tune never get answered.

atr43G363295rwkw.jpg

Link to comment
https://www.sau.com.au/forums/topic/310927-86-64/#findComment-5240099
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Latest Posts

    • The other problem was one of those "oh shit we are going to die moments". Basically the high spec Q50s have a full electric steering rack, and the povo ones had a regular hydraulic rack with an electric pump.  So couple of laps into session 5 as I came into turn 2 (big run off now, happily), the dash turned into a christmas tree and the steering became super heavy and I went well off. I assumed it was a tyre failure so limped to the pits, but everything was OK. But....the master warning light was still on so I checked the DTCs and saw – C13E6 “Heat Protection”. Yes, that bloody steering rack computer sitting where the oil cooler should be has its own sensors and error logic, and decided I was using the steering wheel too much. I really appreciated the helpful information in the manual (my bold) POSSIBLE CAUSE • Continuing the overloading steering (Sports driving in the circuit etc,) “DATA MONITOR” >> “C/M TEMPERATURE”. The rise of steering force motor internal temperature caused the protection function to operate. This is not a system malfunction. INSPECTION END So, basically the electric motor in the steering rack got to 150c, and it decided to shut down without warning for my safety. Didn't feel safe. Short term I'll see if I can duct some air to that motor (the engine bay is sealed pretty tight). Long term, depending on how often this happens, I'll look into swapping the povo spec electric/hydraulic rack in. While the rack should be fine the power supply to the pump will be a pain and might be best to deal with it when I add a PDM.
    • And finally, 2 problems I really need to sort.  Firstly as Matt said the auto trans is not happy as it gets hot - I couldn't log the temps but the gauge showed 90o. On the first day I took it out back in Feb, because the coolant was getting hot I never got to any auto trans issues; but on this day by late session 3 and then really clearly in 4 and 5 as it got hotter it just would not shift up. You can hear the issue really clearly at 12:55 and 16:20 on the vid. So the good news is, literally this week Ecutek finally released tuning for the jatco 7 speed. I'll have a chat to Racebox and see what they can do electrically to keep it cooler and to get the gears, if anything. That will likely take some R&D and can only really happen on track as it never gets even warm with road use. I've also picked up some eye wateringly expensive Redline D6 ATF to try, it had the highest viscosity I could find at 100o so we will see if that helps (just waiting for some oil pan gaskets so I can change it properly). If neither of those work I need to remove the coolant/trans interwarmer and the radiator cooler and go to an external cooler....somewhere.....(goodbye washer reservoir?), and if that fails give up on this mad idea and wait for Nissan to release the manual 400R
    • So, what else.... Power. I don't know what it is making because I haven't done a post tune dyno run yet; I will when I get a chance. It was 240rwkw dead stock. Conclusion from the day....it does not need a single kw more until I sort some other stuff. It comes on so hard that I could hear the twin N1 turbos on the R32 crying, and I just can't use what it has around a tight track with the current setup. Brakes. They are perfect. Hit them hard all day and they never felt like having an issue; you can see in the video we were making ground on much lighter cars on better tyres under brakes. They are standard (red sport) calipers, standard size discs in DBA5000 2 piece, Winmax pads and Motul RBF600 fluid, all from Matty at Racebrakes Sydney. Keeping in mind the car is more powerful than my R32 and weighs 1680, he clearly knows his shit. Suspension. This is one of the first areas I need to change. It has electronically controlled dampers from factory, but everything is just way too soft for track work even on the hardest setting (it is nice when hustling on country roads though). In particular it rolls into oversteer mid corner and pitches too much under hard braking so it becomes unstable eg in the turn 1 kink I need to brake early, turn through the kink then brake again so I don't pirouette like an AE86. I need to get some decent shocks with matched springs and sway bars ASAP, even if it is just a v1 setup until I work out a proper race/rally setup later. Tyres. I am running Yoko A052 in 235/45/18 all round, because that was what I could get in approximately the right height on wheels I had in the shed (Rays/Nismo 18x8 off the old Leaf actually!). As track tyres they are pretty poor; I note GTSBoy recently posted a porker comparo video including them where they were about the same as AD09.....that is nothing like a top line track tyre. I'll start getting that sorted but realistically I should get proper sized wheels first (likely 9.5 +38 front and 11 +55 at the rear, so a custom order, and I can't rotate them like the R32), then work out what the best tyre option is. BTW on that, Targa Tas had gone to road tyres instead of semi slicks now so that is a whole other world of choices to sort. Diff. This is the other thing that urgently needs to be addressed. It left massive 1s out of the fish hook all day, even when I was trying not too (you can also hear it reving on the video, and see the RPM rising too fast compared to speed in the data). It has an open diff that Infiniti optimistically called a B-LSD for "Brake Limited Slip Diff". It does good straight line standing start 11s but it is woeful on the track. Nismo seem to make a 2 way for it.
    • Also, I logged some data from the ECU for each session (mostly oil pressures and various temps, but also speed, revs etc, can't believe I forgot accelerator position). The Ecutek data loads nicely to datazap, I got good data from sessions 2, 3 and 4: https://datazap.me/u/duncanhandleyhgeconsultingcomau/250813-wakefield-session-2?log=0&data=7 https://datazap.me/u/duncanhandleyhgeconsultingcomau/250813-wakefield-session-3?log=0&data=6 https://datazap.me/u/duncanhandleyhgeconsultingcomau/250813-wakefield-session-4?log=0&data=6 Each session is cut into 3 files but loaded together, you can change between them in the top left. As the test sessions are mostly about the car, not me, I basically start by checking the oil pressure (good, or at least consistent all day). These have an electrically controlled oil pump which targets 25psi(!) at low load and 50 at high. I'm running a much thicker oil than recommended by nissan (they said 0w20, I'm running 10w40) so its a little higher. The main thing is that it doesn't drop too far, eg in the long left hand fish hook, or under brakes so I know I'm not getting oil surge. Good start. Then Oil and Coolant temp, plus intercooler and intake temps, like this: Keeping in mind ambient was about 5o at session 2, I'd say the oil temp is good. The coolant temp as OK but a big worry for hot days (it was getting to 110 back in Feb when it was 35o) so I need to keep addressing that. The water to air intercooler is working totally backwards where we get 5o air in the intake, squish/warm it in the turbos (unknown temp) then run it through the intercoolers which are say 65o max in this case, then the result is 20o air into the engine......the day was too atypical to draw a conclusion on that I think, in the united states of freedom they do a lot of upsizing the intercooler and heat exchanger cores to get those temps down but they were OK this time. The other interesting (but not concerning) part for me was the turbo speed vs boost graph: I circled an example from the main straight. With the tune boost peaks at around 18psi but it deliberately drops to about 14psi at redline because the turbos are tiny - they choke at high revs and just create more heat than power if you run them hard all the way. But you can also see the turbo speed at the same time; it raises from about 180,000rpm to 210,000rpm which the boost falls....imagine the turbine speed if they held 18psi to redline. The wastegates are electrically controlled so there is a heap of logic about boost target, actual boost, delta etc etc but it all seems to work well
    • hahah when youtube subscribers are faster than my updates here. Yes some vid from the day is up, here:  Note that as with all track day videos it is boring watching after the bloopers at the start.  The off was a genuine surprise to me, I've literally done a thousand laps around the place and I've never had instability there; basically it rolled into oversteer, slipped, gripped and spat me out. On the way off I mowed down one of the instructor's cones and it sat there all day looking at me with accusing cone eyes as I drove past. 1:13:20 was my fastest lap, and it was in the second session, 3rd lap.  It (or me!) got slower throughout the day as it got hotter.      
×
×
  • Create New...