discopotato03

By battle do we mean dyno or ah drag race . Still lots of variables . Probably a moot point but given a choise Id prefer a 52T GT3071R , mainly because mid trim compressors generally give slightly better efficiencies and if I could get away with using something slightly less bulky than a T04E compressor cover thats a bonus . I figure that Garrett have used T04B and T04E comp covers on those 71mm GT35 compressors and if the trim was down a tad it would not be the end of the world . It'd basically be a GT2871R 52T with a GT30 turbine instead of the GT28 . Who knows - maybe an RB25 housing to make it say NISSAN and fit std plumbing . As for Geoff , its about three days work for his business so many thanks to FullRace Motorsport . Cheers A .

The JJ ones going to be cheaper than genuine and the only one I know of has no problems . I'd be getting rid of the composite tank system if my R33 had a radiator problem .

I think I did see a pic of those once , do they have the stud holes for RB25 and 26 heads ? Also possibly a 52 comp trim 3071R may better suit those not after lots of revs and high boost .

Would I be right in thinking that your asking our opinions on the cost versus risk factor ? If cost was equal go a brand newin but probably not the case . If the second hand usable one was in good condition (need to see the cartridge with housings removed) , if discounted . If the rebuilt one WAS done by someone who can replicate OEM tolerances and durability if the price is competitive . Truthfully the only unique parts in that turbo are the T3 flanged HKS integral gate turbine housing and its 63 trim compressor wheel . The GT2860RS is very similar and with the HKS turbine housing performs much the same . The real trick is to get that direct fit turbine housing because it bolts to your std manifold and dump pipe . After that you have a reasonably wide choise of GT2860 series cartridges and so can set it up to do what you want in that 220-230 kw range . BTW check thotse "GT2530's" your looking at , cartridge number should be 446179-5021 . My list shows the complete unit no's as 472560-0004 or -0011 under HKS . I imagine one is for RB26 type and the other RB20/25 but not sure which is which . I think there was also an SR20 version with a GT25/28 flange and outlet . Your call , cheers A .

I don't think you'll be disapointed . Cheers A .

Hi all , I've had an E mail back from Geoff Raicer to say that he read these TS type threads here . He said the only way to show the difference is to experience both because the difference is really noticable . In about 6-8 weeks he is going to do some dyno testing in the following configs . The engine will be a "stock" RB25DET except for the GRedy (sp ?) inlet manifold and a GT3071R turbo so . 1) Std exhaust manifold with a single scroll GT3071R , not sure which A/R housing , tune and dyno . 2) Change to Full Race manifold with same turbo , retune and dyno . 3) Change turbine housing to twin scroll , retune and dyno . The results should be very interesting though how well the graphs relate to the real world experience is hard to say . I'm going to ask him if he can log exhaust manifold pressure (turbine inlet pressure) and compare or overlay the numbers to the inlet manifold ones . I don't know if they'll get the chance to try a twin scroll GT3076R and GT3582R but it would certainly answer the question of can bigish (not hugeish) turbos be reasonably responsive without being restrictive on the exhaust side (ie resorting to small A/R's) . I think also more TS turbine housings are going to be made available but no details yet . Cheers A .

Whats the owner asking for it ? Cheers A .

Yes nice aren't they . Now lets see , we'd ditch the Hitachi turbo for a nice T3 flanged twin scroll one and .... Good pics , also tells me what wastegate fits - std HKS 40mm . Cheers A .

If you can find the ph no of Robinson Nissan Rockdale (Sydney) they would tell you . I think I'd just buy the adjustable Nismo and set the std pressure . Cheers A .

Yes interested in an R33 RB25DET head , prefer Series 2 . I don't need the cam or pulley just all the valve gear , must have all the original caps and fasteners . If you have a good fuel rail also interested . Cheers , Adrian in Sydney .

I think it was WilliamsF1 here that turned his RB26 road engine into a torque mountain with the -7 type turbos which from memory are similar/same as RB26 specific GT-SS turbos . He did a lot of other things as well and I think the result made his RB26 feel more like people today expect a production engine to feel - sort of 2500-3000 and hang on . I've never driven or even been in a GTR but everyone says that they're just a car until 4000 odd and then things really happen . If I ever inherited a GTR its what I reckon I'd use . Makes the V8's look even sicker I suppose when the legend starts to haul nearly 1000 revs sooner than they usually do . Cheers .

Hi all , whilst looking around at NASOIC (Sp ?) North American Subaru site I found this . Still too illiterate to post links but search this thread - New Exhaust Manifold by Full-Race for Subies ! The first page sets the pace then on the third Geoff Raicers goes into detail of what materials he uses and the kind of welding techniques to make his manifolds long term reliable . I've not read the complete string yet but it looks very interesting so far . The one thing that really made me sit up and take notice was where he mentioned that measuring manifold runner lengths is not the way to go about assessing its worth . He mentions that its the pressure drop from the port to the nozzle (turbine housing inducer inlet) that tells the story , so even pressure drops rather than pipe lengths . Subarus flat fours ie EJ20/22/25 are a prime example of uneven length manifolds with the turbo usually high behind the offside head and the manifold runners from the nearside head passing round the front of the sump . This makes me wonder how well manufacturers have thought about this with std manifolds - possibly the lengths are all over the place but with cross sectional area variations and a turbine housing fitted for testing there may be method in madness . BTW I'm going to try and get Geoff to read some of these like threads and have some input to the whole twin scroll system , he has that much test data from applying this system to lots of different engines in a multitude of cylinder numbers and capacities that its difficult to dispute it . Before I do I really hope the mood does not get caustic because people are going to believe what their comfortable with and to maintain some decorum sometimes we'll have to agree to differ . Such is life , cheers Adrian .

Yes , exactly what you'd have to do with any non std turbo . The difficult issue is generally a non factory style wastegate . Cheers .

Well if you went to those same engineers and said find a better way of putting a measurable and policable devise on those class cars to create a level playing field they'd probably agree that its a neat way to achieve it . The whole turbo concept with competition engines I think came to a head in the F1 era . It was getting harder and harder to to police the rules with fuels amongst other things and power was climbing at a huge rate . It seemed to end up in the too hard basket and Grp A on tarmack only lived on another what 5 years ? Even then out here we had the bullshit "Cams Grp A" not FIA Grp A because the poor 2wd taxis with glorified truck engines couldn't keep up ... Do you think anyone cried about Ford having to remove the silly TA34 turbos off their Cosworth YBD powered cars because the power range was unacceptably narrow with them ? Nope , it forced them to find a better way to live with the limited air flow allowed . The reason its smart is because it makes the engineers think harder about how to make an acceptable power range without increasing revs/boost/turbo size . Actually its a great leg up because as I mentioned the methods flow on to production cars and that can spell increased sales to the public . Trust me the engineers don't give a rats arse if a poorly sized turbo surges in that application , they are far more concerned about finding things that do work rather than those that don't . If anyone followed the development of the Evolution Series Lancers they'd see that the only thing that bears any resembelance to the first one is possibly vaguely the engine block . They evolved right through the Grp A era (some major upgrading every year or two for homoligation purposes) and they sold heaps of road cars which after all help pay the bills . WRC is different to Grp A in that the manufacturers don't have to sell road going cars to make up homoligation quotas , however Mitsubishi Subaru etc sell lots of Evos Rexes etc and the development dollar is paying off . With the gearboxes the ratios still have to be suitable , alternate means of moving the dog rings is fine but the ratios (and the gaps betwen them) have to suit the engines useful rev range . Also the sections they run over these days vary so much speed wise that the ratio spread lowest to highest has to cover a broad speed range . The only practical way to achieve this is to have more ratios with acceptable gaps in between . In class racing there is no fair , there is just a set of rules the cars have to comply with . If you think the knuckle draggers had something to winge about with the Grp A GTR's there would have been some very much more red faces and bent egos had they not had their restrictors . Cheers A .

Yes DR half shafts are a problem in drag apps with high torque and sticky tyres . They tend to brake through the CV's circlip grove in the shaft itself and custom ones of the same dimensions can do the same thing . It may be worth looking into what the Z32 300ZX turbo used for shafts though I think the diff itself was an R230 . Cheers A .

I think you would be far better off running a GT3582R at that power level , even then your not really stressing the thing . Running a larger turbo than necessary for a set power level merely lifts the on boost power range upwards . You would expect the boost enhanced torque to be happening under 3500 rpm even with the 1.06 A/R GT35 turbine housing . Cheers A .

Hi Stocky , the rational is not just about foreign pressure waves beyond an opening exhaust valve . Its also about the cylinder exhausting into an area of lower pressure so the sudden rapid pressure rise means the gas can accelerate more easily and lose less of its velocity between the exhaust valve and the turbine nozzle . To a degree the exhaust pulse/shot/slug moving into a volume of lower pressure is still expanding and this expansion will assist exhaust gas velocity into the path of least resistance . If the chosen path has higher than desirable pressure the expansion rate will be reduced as will the exhaust gas velocity AND the merged gas pulses have a cumulative temperature rise effect on the gas . When its possible to use a larger A/R divided turbine housing than would be the case with a single its all win . I wouldn't be too harsh on the std RB25DET exhaust manifold , obviously its possible to be improved on but to be able to get 300 od Kw worth of gas flow through the thing means its hardly woeful . You don't lose the divided nature of these manifolds because the angles are a little sharp and the runners all different lengths . That moves the exhaust pulse timing around a bit at the nozzles but thats the compromise you get from not using a properly developed competition grade exhaust manifold . By this I don't mean you have to have a manifold like Geoff Raicers to get some benefits but they seem to take the most advantage of of whats going on . Stocky yes there are a few sub 800Hp divided turbos out there but the gap between say 350 and 700 is pretty big and right where we can't take advantage of it . Some of the later IHI VF series , Garretts GT3267/GT3271/GT3576 (plain and BB) GT4082 and probably many more . Just a bit extra from the Grp N/WRC rally world . These classes make the cars run an inlet air restrictor in front of their turbos to basically cap the maximum airflow the engine has available . It really is a clever way of enforcing a maximum power limit amongst competitors . The works teams had all sorts of dramas trying to sort out how to make enough torque over a wide enough engine speed range before the restrictor said no more . They needed to have high torque starting down low and short shift to stay on the boil . They also had smart boost controllers taper the boost off as the revs rose so as to get an acceptable rev ceiling even if at low boost to not suffer massive compressor surge . Anti Lag Systems (ALS) helps but its very hard temperature wise on the system . Close ratio gearboxes make it possible to stay in the enforced narrow rev range and thats why we are seeing six or seven etc speed boxes in the competition cars and nowdays filtering down to road cars . Mitsubishi got on the twin scroll wagon fairly early and Subaru (no doubt the others as well) were not too far behind . It may be news to some but a few years back they were getting 650 Nm of torque out of a 2 litre four that was changed up ratios at about 5500 rpm . These are serious machines basically cross country F1 tech vehicles and they use twin scroll systems to help get them there . Production car manufacturers are using it as well , didn't someone mention in Mafias 300Kw adventure thread that the later Evo Lancer road car is making GTR34 torque but with a 2L four cylinder ? Surely we stand a chance of getting a large portion of that 650 Nm (possibly 3/4 so 487 odd) with a 25% larger inline six . This is 67 more than the JDM Legacy makes with an EJ25 and its quiet and complies with their emission regs - and has a warranty . The current Wheels mag mentions the MY08 Rex which is supposed to land here next year , toned down to 400Nm and a bit over 200Kw . JDM I think 430Nm and 234 Kw ? If these cars are not too porky they are going to have some serious squirt and be pulling strongly under 4000 revs . The common factor seems to be that they make strong torque over a wide range and without massive revs , the turbos are not huge either . Anyhow let the debate continue , cheers A .

They are either IHI VF 37 or 38 turbos using I think what they call the P25 turbine housing . Somewhere out there in cyber space there is an MHI (Mitsubishi Heavy Industries) graph of a single and twin scroll turbine housing on possibly an Evo turbocharger . I didn't save that one because I don't need convincing that is has positive function . The reason I'm pushing for Garrett to produce twin scroll divided wastegate turbine housings is that they would make the GT30/35 based BB turbos more cheaply and easily available and in a more effective format to more people . The way I see it integral gates (and correct turbo matching has a big say in this) are not the bady many make them out to be , ask Mafia what he thinks of his . The Japanese are famous for "bolt on" upgrades and with good reason , all the one off fabrication and customisation COSTS . When you bolt a better turbo to your factory fitted manifold and the waste gate issue is taken care of its another biggie solved . If the thing pulls great torque numbers over a wide range you lose the need to rev piss and pick handles out of the thing to get motorvating . I think if the shove in the back everyone loves starts at lower revs (and road speed) more can get their jollies without going at warp 9 . Its the pulling telephone number revs through not too many gears that puts us in gaol or worse . I don't think warmed over road engines have to have that nothing nothing nothing WHAM power delivery but getting it right means having all its dogs barking and they don't all have to be bull mastiffs . Wanting to do it on a budgets fine but just remember your searching for 5+ litre V8 performance so it was never going to be a cake walk . Just on the VATN turbos I don't think they're a free ride either , Variable Area Turbine Nozzle I think equates to variable turbine inlet pressure turbine housing as well so its not without its compromises . Cheers A .

Oh er something like these ?

Garrett do make an alternative compressor housing for the GT3082R and GT3582R . Its a direct replacement on the XR6 spec GT3582R (which is the same compressor end as your turbo) but wil probably need the alternate adapter ring . This housing uses the same size inlet and outlet as a non port shrouded T04E housing ie ~ 2.75" in / 2" out (70mm / 51mm) . GCG sell them as an upgrade for the XR6 people so you could try them . Cheers A .

To save my fingers and so you people can see it on Garretts website . I'm too illiterate to post links but try searching this www.turbobygarrett/products/turbochargers.html . Scroll down to Medium Frame and on the right hand side under GT30R you will see the three "GT3071R's" and the real GT3076R . The top GT3071R is the REAL one and the other two are the "come in spinner" versions . You will notice that the top one has no turbo assembly or complete unit number and thats because Garrett supply them without a turbine housing . This is done so that the buy can chose which size and style (gated/non gated) he wants and not pay for one he doesn't . If for whatever reason you don't want a Garrett housing (mutter/grumble) you don't have to pay for one . Have a VERY close look at the turbine mass flow and efficiency tables for the dodge city versions AND remember that being T2/25/28 (same) flanged they won't fit your T3 flanged single turbo Skyline exhaust manifold . Can the moderators please make the link to Garretts website a stickey , lots of spec details and its easier to quote those and get people to search rather than retread many strings here . Cheers A .

Food for thought Nismoid , R31's have a kind of lift out fuel pump/swirl pot affair don't they ? Would it be possible to have a fabricated pot made and have its supply (lift) pump in the tank but on the outside of the pot ? All in the tank and self contained if you know what I mean . Cheers A .

Anyone who's been around cars a few years can tell straight away if it has a working cat or not - the smell is completely different . As for flames from the exhaust ? shouldn't be doing that with or without a converter - its not there to be a flame or spark trap . If the EFI system is injecting fuel when it shouldn't something is very wrong or the load/airflow sensing device is sending the computer the wrong messages . Just about everyones got a family and they have to breathe as well . As for unleaded avaition fuel (Av gas) , this is far from the best fuel to run from purely a performance point of view . Any responsable person will run a working converter and high flowing ones are a buy bolt affair nowdays . Every mug that gets busted takes us closer to the day when the RTA will have road side sniffers and the simple cheap light type road side gas analyser . Think about it , you may pass the RBT test/noise test/computer rego check/visual height check etc but if they have a cheap means of sniffing the exhaust (particularly if there's signs of soot and blistered paint) your going to be general revenue's best friend . The authorities LOVE making examples of people driving performance and import cars . For all of our sakes can you please do the right thing . Cheers A .

Hi Trooper , its been a while hasn't it . I tracked down your mate at Chippingnorton and he did did tell me the cartridge number in yours but thats about a thousand bits of paper ago . I remember he said they pressed a collar into your exhaust housing and machined it to suit the turbine which is a novel way to go about it . The details escape me but at the time I thought it was not the way I'd go about it - something about the turbine being a little small for the compressor but its hard to be sure . Those injectors are still in their boxes and will stay that way untill I get my hands on a Datalogit . Cheers A .

Well the cartridge section appears to be a Garrett ball bearing GT30/T04S but someones machined out the VG30 BB turbine housing and R33 Skylines Hitachi compressor cover to fit . I don't think Garrett would use those wheels in housings not designed for them so not too sure . The current GCG Hi Flow uses a smaller 7/14 blade compressor with a slightly larger turbine of a different family to the GT30UHP . I don't think I ever saw the higher capacity GCG Hi Flow but if anyone has a pic of one looking at the compressor I'd like to see it . As to if it will surge ? The only way to know is to try it . Had it been me I reckon I'd have used the GT2871R 48T BB cartridge like I think Dale FZ1 did because its wheels are a lot closer in size to what the Hitachi housings were designed to work with . Cheers A .