discopotato03

Nissan fitted them to RB26's ... A .

Properly port the head , fit slightly over sized exhaust valves and bump the compression ratio up to 9.2 - 9.3 . What are we calling a T04 ? A .

As for Nissan live rear axles I can add a bit . From memory one of the larger so called luxo barges like 260C or 280C had a Japanese H190 differential and those are reasonably durable - compared to a Borg warner 8. something "Ford Diff" . Damn local content in Nissans of that era . LSDs are a bit exy though some JDM Nissans had a production plate LSD in them . If you can find one and are keen enough to fit it the JDM semi trailing arm IRS gets you into a long nose R200 and is a step up from a live rear end but not as good as multi link IRS like R32/33/34s have . You are at a cross roads here where you can spend a lot and risk painting yourself into a corner with an R31 . Their limitations are 4 stud hubs (limited bolt on brake options) , macpherson front struts and at best semi trailing arm IRS . They are also heavy cars . The Aus spec interior is a bit plasticy in some peoples opinions . Now your call but you get a quantam leap (quote SK) in technology going from R30/31 to R32 and beyond and I'd think you could probably find a clean R32 GTST for not too much money in the scheme of things . You could plonk the RB25 in an R32 which already has 5 stud hubs , far better suspension/brakes/std R200 and is wired and plumbed for an RB twin cam . Add the R33/34 turbo RWD gearbox and have a pretty good package . I built a Bluebird with the whole DR30 driveline and was not happy with it , I then had a DR30 and was not happy with that either - just added dinosaur steering into a longer better trimed package . Your call , cheers A .

Yeah mine is not the easiest method but it just means that you can use this adapter sub loom to plug into the Z32TT one and go back to std quickly and easily if required . Sort of what the Japanese'd call a "bolt on" thing , the AFM is bolted on ... Cheers A .

Hi all , lots a people who use Power FC's on R33s give some thought to using the Z32TT AFM and although wiring them in is not a biggy I though this idea may interest those who don't like cutting std wiring looms . I bought my Z32 AFM from that place in the same approximate area as Silver Water Automotive but on the other side of the main drag . At the time I asked about the plug adapter and was mistakenly of the opinion that it would plug to the std R33 AFM plug and the Z32 AFM , should have learnt by now never to assume anything . I think the bite was 30ish dollars for the "flying lead flat plug" and I though nah at the time . Someone here mentioned that VL Commodes use the same plug fitting as the TT AFM and I haunt Pick and Payless so I grabbed (cutters) a few next time I was there . The thing I couldn't find until today was an AFM that used the same 3 pin fitting as the std RB25's one , turns out 1995 Mazda 626's use the same thing so I murdered a couple of those to get the male side of the union . Like on the 25 AFM the fittings plastic shroud is held to the AFM with two phillips head screws but it wont come apart because the three steel strips inside are soldered to a circuit board and there's silicon gunge to seal crud out . You need to "persuade" the plastic lid to exit the unit and then you can see where the steel strips come in from the back of our male plug . You can snip these with wire cutters (in front of the resistor like striped gadgets) and feed them back through the silicon sealant - once the external screws are removed . So now you have the male fitting and it plugs straight into your R33's female AFM plug . If you got yourself the 7 pin flat plug from a VL what you now need to do is join them together and you have a solution that requires no tools to plug into a std AFM or the Z32TT one . To make the new male fitting workable you could solder three wires to the thin steel strips and use something to glue it together so that the steel strips wouldn't work harden and break off with vibration etc . Maybe Jaycar has something that the plastic shroud could screw to in the way of a proper plug backing and that filled in to support the new wires/steel strips . Any thoughts ? Cheers A .

Busy today Roy but will sniff around the compressor situ . I don't suppose you have pics of your turbo you could PM me ? I think Trust may have speced a few specials but need to do some searching . An American site called Melett has some Mitsy turbo specs like shaft dimensions . Also GT pumps here in Aus advertise that they do Mitsy mods as well . Early Evos , pre Evo 4 , had normal rotation turbos so it may be interesting to see what they did with those . Later , cheers A .

Two things could be looked at here IMO , firstly you could try using the matching Tomei exhaust R33 Poncam and refitting the std VCT assembly . I am curious to know what made you decide on the 260 10.5 Procam on the exhaust side . Correct me if I'm wrong but is the 260 10.5 an RB26 or Neo25 cam ? Secondly , some will disagree , consider using the larger 2835 Pro S 0.87 A/R turbine housing . I know people have different ideas about cams and turbos but if the power output and detonation threshold falls then I think it's trying to tell you that the combination is not so good . I haven't heard too many people say that R33 Poncams were a backwards step , also IMO headwork done well really enhances the breathing and performance everywhere . My thoughts only , cheers A .

Yes that is true , the trim sizes are 52 and 56 . Geoff had a post in Supraforums I think and he was doing comparisons of power outputs and turbine housing size on GT4088R's , I believe his findings were that using larger turbine housings was the way to male the power without high (40 psi) boost pressure . I'm curious to know what sort of response is being asked for from this stretched RB27 . Cheers A .

Of the three you mention I'd give the GT4094R a big miss , basically a GT4088R with the GT4294R's compressor wheel and not surprisingly a poor combination with the 78T GT40 turbine . Personally I think the GT4088R is a better unit mainly because it has more current wheel designs which is a bonus . The T04Z's turbine (T04 P trim) probably dates back to the 1960's so a lot of engineering water has passed under the bridge since then . There is a lot of variation in what gets called "T04Z" mainly with the turbine housing . A/R sizes all over the place and single or twin entry turbine housings in big T4 or smaller T3/twin T4 Euro flange sizes . I wouldn't even bother contemplating a T04Z with a single scroll turbine housing unless it was one of the three HKS ones . You should really E mail Geoff Raicer at FullRace Motorsports in the US because he really likes and has had great success from GT4088R's and always says that if the engine/manifolds/turbo are properly set up they are not especially laggy . Aside from just the wheel designs in this turbo both are significantly different trim size wise and that seems to make all the difference . Garrett usually use the 84 trim size with their GT UHP turbines ie GT30/GT35 and the proyptype GT4088R did as well , at some stage they settled on a 78 trim size for the GT4088R and it also is available on the diesel GT37xxR turbos . The compressor wheel design I believe was a first for Garrett and to me looks like typical GT blade form but with 7/14 blades instead of 6/12 and in a 52 trim size rather than the usual 56 trim size . The T04R compressor wheel in the "T04Z" turbo is an older T series design and being 63 trim is dated thinking IMO compared to later petrol engine designs and even diesel engine designs . Recently people have been looking at Holset and BW diesel turbos , often they use big wheels in smaller trims sizes than Garrett usually does with GT BB turbos but the downside at times is their massive housings . Anyway speak to Geoff because he's played with RB26's and GT4088R's so he should be able to give you an idea of what to expect . Cheers A .

Go to the Datalogit site and look under distributors , the Australian one is in Tasmania and if he has stock the service is good . Can be hard to contact sometimes but keep trying . Cheers A .

Well OT but IMO you could have made more than enough power with a GT3076R which for its size is a better thing than a GT3582R in small turbine housing form . 2WD RB25 , how much can you get to the ground . My opinions only , cheers A . BTW has anyone looked into the large frame BB P/60-1 ? http://www.atpturbo.com/Merchant2/merchant...tegory_Code=GTB http://www.atpturbo.com/Merchant2/merchant...tegory_Code=GTB Cheers A .

Yeah that was going to be my question , the GCG Hi Flow with the VG30 0P6 turbine housing . Internally they are a fair bit bigger than the RB25 housing so with other top end work they are supposed to go well and not have any extra turbine lag . I'd like to see better wheels in the high flow but I think it may be a case of the small frame GT BB turbine shafts being too small/short and the larger frame GT turbine shafts being too big in diameter . A .

"Adjustable" actuators are adjustable for length not rate . A .

The exhaust side should be much easier because no existing RB25 stud holes need to be filled in . Other people think and I agree that Nissan changed the RB26 exhaust stud pattern to stop people using RB26 bits on RB20/25's . Looking forward to seeing it all running , cheers A .

No and you won't run a GT3076R to its gas flow limits with a 0.82 A/R turbine housing . You need to go back to the turbine flow map of the GT3076R (700382-12) and see the difference between the 0.82 and 1.06 A/R turbine housings . I really can't understand why people make the jump from GT3076R's to GT3582R's without having tried the 1.06 housing first . Blind Freddy can see from the maps that most are running out of exhaust flow not compressor pumping capacity . There is no guarantee that a GT3076R with with a 1.06 turbine housing will have a higher boost threshold than a GT3582R with an 0.82 hot side , what you can see is that the petrol GT30 turbine map looks a lot better than the petrol GT35 one . I've had suspicions for a long time that Garrett jerked everyone off with the turbine housings on 3582R's , I suspected that they were machined out GT30 castings and someone here recently confirmed that they "make" GT35 housings out of GT30 ones if they can't easily buy them . The upshot is that you get a higher expansion ratio in larger A/R turbine housings and if the turbo is sized properly you often don't get the turbine lag that people quiver over . If you want to look at diesel engine turbos there are only a few with the 76.2mm GT37 compressor - GT3576 and GT3776 . Both use GT40 compressor housings and compared to petrol GT3076Rs huge hot sides . To have any hope of getting all 43 beans out of a GT3076R you have to use the 1.06 turbine housing . A .

Some interesting snippets getting around here . What do we all think about splitting threads and having one for the Vipec and another for the latest Link management systems , I'm always interested to hear peoples opinions and experiences with aftermarket engine mamagement systems . Also some info about developing things from Adaptronic would be interesting as well . Cheers A .

A bit of a grey area but I think S200SX's and S300SX's are original BW turbos , mobs in the US alter them and hang slightly different names on them . Geoff Raicer (fullRace Geoff) is the one to ask about them . A real GT3076R with a big A/R twin scroll turbine housing is supposed to top out at 570 Hp . A .

Out of those two the GTRS would be the better choice for any RB25DET . The two variants in the GTSS group are truly unique , the RB26 type is discussed elswhere here or you can search for it at turbobygarrett under GT2560R and -9 . The second type I think is intended to be a CA18 or SR20DET upgrade , cartridge wise its like a GT2530 but with a 60 rather than a 63 trim 60.1mm compressor wheel . Probably best suit a CA or SR with a std computer and better exhaust . I don't think I heard of HKS selling the second type GTSS with a T3 flanged turbine housing , possibly it would be OK on a mild RB20 but very tame on a 2.5L 6 I'd think . Most people agonise over GTRS or GT2835 Pro S , cheers A . PS Don't forget the BB Hi Flow .

If you are talking about the Garrett 0.86 A/R GT28 BB turbine housing I think you'll find they are not the same style as RB26 specific GT28BB turbine housings . Have a close look at RB26 style turbos on the turbobygarrett site , they tell you that the housings on these turbos are the "compact" style and are not intended really for any other app . From memory the dump pipe flange is different and the housings neck aimed slightly differently from generic GT28 BB housings which are really aimed at SR20/CA18 type single apps . I have not seen the 0.86 GT28 BB turbine housing machined to suit the turbine in the "-9" or RB26 type GTSS . They should fit the SR20 type GTSS but that uses a different turbine to the GTR variant . Cheers A .

Your calls I guess but I'm more interested in function and cost than advertising . Really IMO PS housings turned up on HKS spec Garrett turbos because they knew people would run them with smallish A/R turbine housings and that they would surge with bigish trim compressor wheels . If you go right through their range of petrol engine turbos you'll see that they also usually had a few optional compressor trims and that makes a difference too . Smaller (than the largest) wheel trim options is not such a bad thing response and thermal efficiency wise , with many wheel designs its often the middle trim size that the sweet spot and larger or smaller trims intended to bridge the gap with the existing and next larger or smaller diametre wheel families . This is getting a bit off the track but I'd say the origins of these petrol BB GT (30/35 series) turbos came from HKS wanting Garrett to use their most modern wheels and putting them on a shorter smaller sized cartridge than they were designed for . To make them "spool" early the housings also need to be small compared to diesel engine housings and this is why I reckon people have surge or creep problems . If you use or recreate exactly a HKS model specific turbo you shouldn't get the problems because someones already sorted them out . It's not the same deal with a Garrett generic turbo because they don't have the fixes in place , that's left to the user to sort . Outa time , cheers A .

Any port shrouded turbo can make the sonic shriek , the thing that gets around it is the bell mouthed insert like HKS uses on their GT3037S turbos , Holset sometimes uses them as well . The sound is sonic vibration caused by the splitter blades inducer tips being partially exposed at the slot . GT3582R turbos are really a Garrett hybrid , they use a compressor housing intended for T04S turbos . Of all the GT25BB center section turbos the 3582R's turbine shaft is unique in that the section where the compressor wheel fits over is slightly larger in diameter than the GT2554R to GT3082R BB range . I'm not really sure if size for size (A/R ratio) GT30 and GT35 turbine housing castings are the same . Garretts always said they are outline interchangeable so it's not impossible that they machine them out larger for the 3582R . Be a bit careful with the Garrett large frame plain bearing GT type compressor housings because often they are 0.54/0.58/0.65/0.72 etc A/Rs but of the GT40 family not T04S like GT3582Rs use . The housing family is really based on the compressor backplates diameter and offset , actually the compressor wheel offset and bore size is also different between a BB GT3582R and say a GT bush bearing GT3776/GT3782/GT4082 . Garrett actually modified 82mm GT40 compressors for their GT3582R and HKS spec "GT3240R" (56T and 54T) , the bore size is smaller and they've machine the back of the wheel to have a less prounounced tulip shape . Also they machine most of the hexagon off the front of the wheel so a lock or jamb nut can be fitted to suit the thread on the small frame BB style turbine shaft . Really the small and big frame GT turbos are worlds apart , I have a big frame GT3576 56T turbo I must get some pics of and post . The housings are 0.65 and I think 1.18 but they are HUGE next to a GT3582R's . Cheers A . BTW Bretts on the money , Garrett are starting to produce a factory port shrouded 0.70 A/R T04S housing for the GT3582R and no doubt he'll get them in soon . Lastly don't forget that PS housings cost a few points of compressor adiabatic efficiency so they can be a slight step backwards if the thing is not surging , like most solutions they are a compromise with surge being the greater of the two evils .

Will have a look into those , cheers A .

Guys I'm a little lost here , are you saying that a modded R33 GTS25T computer can be made programmable and tuned via the Consult port just like any after market computer ? I was under the impression that ROM chips had to be burnt and erased and reburnt time after time . If all is now good is the software available for anyone to use ? Cheers A .

Hi all , I just read through this whole thread and a possibly silly idea occured to me . Some late model cars don't have a return line from the engines fuel rail at all and I had to ask a long time mechanic mate of mine how such a system could possibly work . He claims that they do actually have a pressure regulator and return but its close to the pump so possibly in tank ? So me thinks what would happe on a conventional fuel injected car like an RB powered Skyline if the fuel pressure regulator was moved to a "T" piece a little short of the rail itself . My thinking is that the heat is conducted from the manifold to the rail (or hot ngine bay) so if you could have a return supply system with one side of the T heading to the rail and no rail return do you get around the thermal issues . The unknown is how hot would the fuel in the rail itself gets and what if anything the manufacturers do to get around it if it is a problem . One things for sure , if in a hot state you stood on it the supply of fuel comming down the line should be cool once that in the rail had been used . If this system is workable it should be reasonably cheap as all you'd be doing is moving the reg and adding a T piece and short runs of new EFI hose . Thoughts ? Cheers A .

Yep I agree with the Haltechs - at least the early ones . I was never comfortable with how they had the software - gauge pressure instead of absolute and their innitial resistance to sequential injection . The early ones possibly were short on processing power and the loom sockets limited in pins and wires . I don't know if they stayed with the bar graph interface but that was hard to stomach too . I played with an E6 an F9 and them an Autronic SMC which software interface wise was much much better - once I learnt to set the charge temp estimation table properly . The major limitations I found to be manifold pressure sensing because setting air temp corrections was so critical and if it's wrong the tune can be a bit eratic . The only people that ever convinced me that MAP could be ok were the fellas at Allen Engineering (Malalla in those days) but they parked a MAF sensor in front of the engines air intake when they tuned their Autronics and logged everything . That way they knew how much air was going in and its density in one simple 0-5v signal . So for me EMSs have to be able to run from mass air sensors which at the moment means a Power FC . Truth be know the best Skyline computer could be the standard one with something better than flash memory so it could be tuned in real time and saved like in a PFC or other aftermarket computer . The ViPec does look very interesting and I hope in future ways can be found to make knock sensing systems fast and accurate enough to prevent engine damage . Need the mass air software , cheers A .