discopotato03

T51R is what HKS call their versions of the Garrett GT42R , T51R KAI is similar to a GT4294R and T51R SPL similar to a GT4202R . Cartridge wise the main difference is that the HKS options use that 82mm GT42 turbine in 76 trim and Garretts market versions the 82mm GT42 turbine in 84 trim . HKS have also optimised their housings for petrol aftermarket apps . First thing to know is which TO4Z ie HKS or Garrett marketed version and is it worth a try on the new engine first . What power characteristics are you trying to change ? What things are different about the new engine compared to the existing one ? Also between the TO4Z and GT42R families is Garretts GT4088R which is worth a look . Cheers A .

Hi Cubes , I wouldn't mind a link to that discussion if possible . It may also pay to go back and look at Maximum Boost and Corky's views on pipe diametre vs turbine exducer or outlet diametre . Gas speed has a lot to do with determining pipe size obviously the larger diametre means lower velocity but its still going to be highest at the most restrictive point . The easy way to measure this is to tap into the exhaust at various points along its length and measure the pressure . I think we all know that for maximum effort power with a GT3582R your going to be using the largest 1.06 turbine housing available for the greatest flow with least restriction and less gas bypassing going on . IMO the easiest way to make a compact dump with a healthy tube diametre is to copy what HKS did with their dump pipe for the Pro S IW housings . This would not be terribly difficult to fabricate though time consuming , has the added advantage of keeping everything at a more uniform temperature than a totally divorced tube so less likely to crack with heat cycles . Cheers .

Guys I think this will always come down to the individuals ideas about practicality . As much as I like them I will never own a GTR because they have a habit of being a financial nightmare . The cost and effort that goes into keeping these cars in tip top condition is something else . Then there's the can't leave it anywhere and car jacking issues . There are limits to how hard you can drive a car on the street and using anything close to all a GTR can dish out will put you in gaol and deservedly so . With some reluctance I voted downgrade because I believe the R34GTT is a car that can be practical fun without costing investment property dollars . You can sink cubic dollars into any GTR but try getting it back when you tire of it or sell it before it ruins you . The thing that I keep coming back to is that GTR's are not the class leaders when it comes to production class motorsport . For whatever reasons Evo Lancers seem to get it together better on the track so what the differences are - possibly weight and suspension design - it works . There will always be a place in my heart for the R32GTR given what GMS achieved with them but they can be beaten by design or engineering over design . Tiz the way of things . My opinions only cheers A .

To each their own , the Hitachi housings are designed to work with a turbine a fair bit smaller that 60mm and nothing like the UHP one . Next time you see a propper GT30 housing have a good look at the volute size/volume/nozzle shape . Compare this to a Hitachi housing thats had the centre machined out of it and tell us they look the same . Then fit each one alternatively and compare the response and turbine inlet pressures . You always find that TIP is up and turbine efficiency is down on what the Garret housings can do . All this for the limited convienence of being able to bolt up the std flange style dump pipe . Since everything else around the turbo plumbing wise has changed and serious punters are going to use a fabricated dump pipe anyway why not use the housing designed for the job ? That housing Lithium has is a Ford style of Garrett turbine housing known in the US as the "5 bolt T3" , the aftermarket ie Turbonetics have had them cast as well . This is the one I often mention when people try to compare the Nissan T3 housing used on Z18's , FJ20's , VLT's , 280ZXT's to the larger turbine series T3's used in the US . As I've said Nissan opted for the small turbine series T3 (59mm turbine series vs US type 64mm turbine series) , their housings cope better with non std (larger) turbines than Nissans ones do but still far from ideal . Its also the reason why T3/T04E hybrids worked better in the US than here - more turbine diametre AND a housing designed for the turbine diametre and tip height . Things to do cheers A .

Any theories on why the bores or bearings would suffer any more wear with the engine coolant temp at 70C . Someone I know swears that the bores won't be round at lower temperatures but I fail to see how 5-10 deg C would make very much if any difference . An oil cooler and bypass thermostat may be needed to get oil temp up from cold in winter and reasonable in summer . Cheers A .

Started this yesterday and Wi Fi dropped out right at the Post New Topic Point ... @#&^($%#@ ! I'm interested in anything that can allow me to use a bit more low/medium speed on load ignition advance and avoid the detonation . People who've been developing engines for ages seem to agree that running a coolant temp of ~ 70C is the sweet spot for maximum power output . This would not be hard to achieve (with the right thermostat) but the sorts of viscosity oils some people run may have problems . I'm wondering what people think about running lightish oils like for example the Mobil 1 10W30 so that the oil does not need to get real hot before it flows easily . I do realise that it needs to get hot enough to boil off any condensation and combustion products if its to have a reasonable life ie 5000 K's . So what do you think of water at 70C and oil at say 85C to bring down combustion chamber temps ? Thermostats . I only know of the std I think 76 deg and 62 deg Nismo thermostats for RB's , is there anything in between . Cheers A . I remember Gary saying they use a Davies Craig electric water pump (race car) with speed controlled by the Motec to regulate temperature without a thermostat . If Davies Craigs "intelligent" speed control box could be relied upon and the pump body made of aluminium I'd go that way too . I still don't have faith in the composite pump body because its engine damage time if it cracks/leaks .

I'm not sure if I'm really sold on elec fan/s in road cars (RWD) , I think its a flawed system that lets things get fairly hot before intervening and then dumps a lot of heat into the engine bay . At least with an engine driven fan its the thermostat regulating the coolant temperature (assumes the rad and fan can cope) and its not an on/off thing over a set heat range . OEM conditions where manufacturers like things hotter than I do it seems to cope somehow . Cheers A .

Another thing I forgot to mention is like Nismoid said your typical BB turbocharger in this range costs about $1700 and upwards . This INCLUDES the turbine housing though buying them without one costs considerably less ie 4-500 . If a dealer was to supply one to you without its turbine housing and bore yours out to suit (maybe an hours work to machine and fit) and still asking approx 1700 he's doing rather well isn't he ? Propper Garrett GT BB turbine housings are expensive partly because they are generally made of high temp materials like Inconnel or one of the other super alloys . Cheers A .

Yes you can machine the guts out of a Hitachi exhaust housing and that lets you bolt the turbo to the manifold and dump pipe to the turbo . The problem is that the turbine housing was designed to have suitable gas flow velocity for the standard engine/turbo and the manufacturers desired power characteristics . Turbines are designed to work with their matching family of turbine housings and very rarely work as intended with other types . Turbines come in a huge variety of diametres/trims/tip heights/blade numbers and blade forms . They are specifically designed to suit a turbine housing with the matching nozzle/nozzle inlet diametre (and width) and volute cross sectional shape and volume . Because there are countless thousands of variations its almost impossible to throw non native housings and turbines together and have a hope of expecting them to give a good result . The problem exists because people want to compromise the whole upgrade effort by finding any means of getting the desired turbo onto their exhaust manifold . The original goal was to get better performance not just to hang the turbo off the engine with the cheapest dodgy means available . Doing it properly is often expensive but you can't cut corners here and expect it to work as intended . To think otherwise assumes you believe the people who design and test these things are morons and don't have a clue what they're doing . Wrong . Far more work (development) goes into turbine and housing design than the cold side because its the power source for the compressor end . Get it wrong and neither the turbocharger or the engine gets to function properly . How well do you want it to work ?

I think I can see what your getting at but possibly you could have asked about single turbos for RB26/results/turbine housing A/R . That last one (turbine housing A/R) is going to depend on turbine and compressor size and availability . Its as simple as that . Often you'll find that three sizes are available (ie .6x .8xx 1.xx) and if you had no information to work off the mid sized one is the logical starting point . That way you get a result and know which way to go if the first try didn't get you what you wanted . There is a tendancy for people to look at maximums with turbos and while a turbo may be capable of high specific output it doesn't necessarily mean an engine can run it to its limit . A huge turbo with a small A/R turbine housing is wasted because even if you could spin the thing fast enough to make the compressor work the small turbine housing won't pass the exhaust gas required to make the ENGINE work properly . Balls vs bushes . Its hard to make a direct comparison these days because manufacturers like Garrett use different (read more modern) turbines and compressors in ball bearing turbos that bush type . It stands to reason that they wouldn't sink development dollars into a turbo with an expensive ball bearing centre section and use dinosaur wheels . Many of their bush bearing turbos like TO4S's and T04R's use old world designed turbines like the P trim TO4 which work ok but not what you'd call brilliant , its because they are based on 1970's technology and thats not yesterday . TO4Z's are an example of dinosaur turbine with modern bearing system and a well matched compressor , in HKS form the housings were designed to get the best from the wheels they use . Bush bearing GT40's are more modern designs and sort of cover the TO4S/TO4R/TA45 range of older turbos . To look at a GT4088R ball bearing turbo next to one of the larger GT40 bush bearing turbos the differences are not always obvious and they can at times use the same style of housings . The ball bearing one is usually designed around higher temp spec turbines and housings and trim better suits petrol engines higher EGT's . The bush bearing type is usually intended to suit diesel engine characteristics like less expensive materials (lower EGT's) and different exhaust flow vs power characteristics . In the case of the GT4088R the turbine trim is good for its frame size and it uses the later 7/14 blade compressor design in 52 trim and has impressive comp map . The larger GT40 bush bearing turbos use a larger trim turbine and A/R turbine housing to suit some OEM diesel app . Volume sales to diesel engine manufacturers dictate the market here . Bottom line you get what you pay for so sometimes old wheels in good housings with a good bearing system are plenty good enough . Cheers A .

Hi Cubes , you say the EL fans fit between the A/C condenser and the radiator so in front and push fans so to speak ? I'd be interested to see pics as well . I can't help thinking fans behind the radiator would work better because in a propper shroud they can draw air from the total core area rather than pushing from the front and only over as much area as the fan/s themselves . Incidently I came across a radiator and twin fan assembly from a Maxima (can't remember 2.4 or 3.0 L) . It looked sort of similar to an R32 GTR rad and a good relatively slim set of fans in its shroud . I have some theories on cooling strategies but a O/T here , over to FI . Cheers A .

I'm talking about the sorts of cams commonly available in the aftermarket - 26 something by 10 odd mm lift . If he wants to keep the state of tune of the engine suitable for std gearbox/diff ratios long periods cams may make it peaky . Falling off the cams is no better than falling off the boost threshold . The burning question is what useful power range and starting where . Cheers A .

Plugging the VCT oil supply in the block should not be an issue but sealing water in at that front gallery may be a problem . The logical solution is to build the RB30 up with your RB26 head and not get side tracked with short term fixes . This way all your financial and time resources are going into the final product . I believe people have used RB25 sensors and loom/PFC to run the RB26 heads electrics . Cheers A .

TO4Z's are really easy with turbine housings , ANY TO4 P trim turbine housing bolts up to them in a myriad of A/R sizes , and single/split T3 flange or single/split T4 flange or single/split TA45 flange which is sometimes called T4 International . The only thing to watch using Diesel spec turbine housings is that they sometimes develop cracks over time because the material spec was intended for the Diesel engines lower exhaust gas temperatures . Garretts GT40 range of bush bearing turbos are more modern designs than their TO4S and TA 45 ranges . Better cartridge and wheel technology though not right up with the BB GT4088R . This ones a ball tearer depending on the airflow required and even has the high temp spec turbine and housings for petrol performance apps . The down side is a retail price of someting like $2750 . With our rising dollar and sales competition it may get better . Cheers A .

I agree , with the cost of close spaced gear sets and final drives these days most find it easier to make the engines power characteristics suit the available gearing . The GT3582R is probably going to cover what you want to do but cam selection and headwork will make changes to its power delivery . The secret would be making lots of mid range torque and not having it start at 5500 revs . Most people developing engines to do this use cam profiles with a fair bit of lift but not the extended valve open period (extended duration) . Cams like this don't need to bet set up with a lot of overlap which turbo engines don't tend to like if they have a restrictive exhaust side because they get reversion . If you can uncork the exhaust side and run high octane fuels the static CR could probably stand to come up a bit from 8.5:1 . Depends on budget I suppose . Cheers A .

I would have thought a ball bearing TO4Z would not be the end of the world these days depending where you got it from . If you know someone who can strip BB turbos a cheap way to build a TO4Z is to buy a Garrett T3/T4R , one of them is a TO4 P trim/60-1 hybrid (cartridge or CHRA no 757179-0001) and that compressor can be flicked for the TO4R compressor that TO4Z turbos use . Some machine work is required because often bush bearing compressors use different back spacing to ball bearing ones . HKS's TO4R is just the same P trim turbine /TO4R compressor with a slightly cropped turbine in bush bearings . The part nos for the wheel , housing and backplate are 451470-0001 , 409722-0023 , and 408997-0018 in bush bearing TO4S outline form - according to my data . It shows the wheel as BCI-8D family . Cheers A .

I've never ever seen a Garrett or HKS marketed GT3037 or GT3076R with a .70 A/R compressor housing . Both sell versions of the GT3040R/GT3082R with .70 A/R TO4S compressor housings . Garrett do make a .70 A/R TO4E compressor housing but they only turn up on Diesel turbos . Cheers A .

Yep me neither Michael , I'm sure its the messages people and their cars sent out when they drive them on the street . Cheers A .

No just the kit not the turbo .

Another option is to weld extra bosses to the RB26 head , mill it flat and then drill and tap . Just be very sure the fabricator knows what they are doing . End up with hybrid tart head that will take any manifold . Cheers A .

The GT3776 uses the same 52 trim 76.2mm GT37 family compressor as the GT3037S/GT3076R 52 trim . But the wheel uses different backspacing in a GT bush bearing cartridge than a GT ball bearing cartridge . You would most likely need at least a custom backplate to set the housing in the right place in relation to the comp wheel . If you really wanted to go down that road a .50 A/R TO4E housing properly profiled would be much easier , could also get it drilled and slotted if its the big or 100mm (4") inlet boss type housing . HKS make their own custom .50 A/R port shrouded compressor housing for the GT3037 Pro S . Difficult to see how that trumpet mouthed insert would drop the turbos boost threshold 500 rpm , the ported shroud helps but dunno about the insert . I don't recall people saying that the HKS GT3037S shrouded turbos scream too much but everyone says the port shroud housings do this in std form . I guess the wheel inducer tips turn pretty fast and the narrow slot is a good exit for high speed gas and sound waves . We need someone with an original insert to measure it up because 150 sounds exy for a piece of machined aluminium though the sections that have the grub screw holes may have been milled so a bit of time involved . I think the inner side of the boss is tapered on those Garrett housings so if it were turned parallel mounting the insert would be easier with cut setions of the right diametre and thickness aluminium tubing . The section near the wheels inducer has a nice groove to centre and seat the insert . Dale what I mean is that doing the head work makes a very real difference to an other wise bog stock engine including the factory camshafts . This means an otherwise std engine not std cars IC/ECU exhaust etc . That car gets full boost from its STD turbo/manifolds at 2000 rpm with good fuel and tuning . I believe its possible to get very usable road car power from making this an early mod because I think the power can be made with less extreme external bolt ons . I also think its a step in the right direction because what most of us want is not what Nissan intended the thing to do . You can force low boost torque out of any engine with smalish turbos but you pay the penalty higher up the rev range . Better to get all the low/med engine performance possible and then enhance it with the turbo IMO , atmo charged torque first then turbocharged torque second . An engine thats only any good on boost leaves a lot to be desired IMO , it makes people want boost from low revs and as we know you can't have it right down low and right up high , physical impossibility for a rotary compressor to charge a piston pump over a wide speed range when driven by its exhaust gasses . Compressor capacity and efficiency is not linear and neither is the turbine sides abilities . Just on VATN or variable area turbine nozzle turbine housings . They are not a completely free ride . Ensuring the gas speed through the turbine blades is enough means there WILL be some turbine inlet pressure (backpressure) . Depending on how the wheels are sized they can give a good average ratio but will never be as good as a conventional turbo designed to work in a very narrow or single engine speed range . They are still a compromise limited by a rotary compressor and its fixed gas path . Anyhow Trooper here is the one to ask about the GT3037S/GT3076R's real world experience because I'm pretty sure thats what he has (according to one source) but still to be confirmed . From memory he said ~ 270 Kw , starts to get some positive pressure ~ 2600 revs and gets busy quickly from 3000-3300 up . I think it was run to 18 + lbs boost with the tuners choice of 98 oct PULP . Turbine housing is supposed to be a Garrett GT30 .82 A/R IW type on a std manifold with a spacer plate to clear the comp housing . Anyhow ask him what he thinks of it . Cheers A .

Unless I'm misquoting I was told std Rb25 head exhaust port will flow ~ 68% of inlet port . When this rises to ~ I think 74-75% they work much better . I think by the time the RB25 inlet manifold becomes a serious problem the factory tool for the job (RB26 top) is the solution . I know its expensive and doesn't go bolt to an R33 RB25 block but its the least limiting solution for an RB30 bottom end . Best factory inlet/valve train/std porting - but still needs work and arguably still lacks valve area for 3 litres . For me personally I don't see a future in a very non standard and please defect me officer type manifold . Just my own thoughts , cheers A .

Mafia you'll have to refresh me , are your head and cams factory std ? Also yes those port shrouded comp covers do the RB211 (jet turbine) thing . Looks aside I think this was part of the reason HKS had the trumpet mouthed insert in their GT3037S comp housings . The "lag" factor is why I'm going with the 52T compressor version and the .68 A/R GT3037 Pro S exhaust housing if I can find one . For what I want I think Garretts .63 may be a little small and their .82 a little big . Forgot to add , Garrett don't make a T3 flanged GT30 based exhaust housing for the cropped turbine in your previous turbo . One of the realities of the GT30 UHP turbine is its trim size - 84T , thats not exactly small and it was designed to have reasonably high gas flow particularly in mid and upper exhaust housing sizes . This is what it takes to get 500 Hp worth of airflow and exhaust into and out of this turbo . The turbo neither knows or cares if the engine can produce the gas flow , the head/valves etc have to pass the gas as well or its not going to happen . Divide 500 (Hp) by 2.5 (litres) and you get 200 (Hp per litre) which is getting up there for basically a production engine that put out just under 100 Hp/litre . To get user friendly wheel it round town power you have to do the sorts of things you'd do to the N/A version to make it breath down low - basically drag the dynamic CR up and have low pumping losses and reasonably high trapping efficiency . Its quite easy to see why Nissan went with the involved and expensive to produce multi throttle inlet system on the RB26 . Having this system allows virtual atmospheric pressure right to the inlet valves when they crack open at lowish revs . So it allows atmospheric pressue to charge the cylinders more easily than the single throttle type manifold can . Try one day watching your std boost gauge and note if its not on the middle peg before the turbo/s start to boost . If the pressure falls before the turbo/s spool up giving positive pressure then the engine is not getting enough atmospheric pressure driven airflow to feed the engine all it wants and so the dynamic or effective compression ratio drops . When it does there is a power dip or lull because until the hair dryer artificially pressurises the inlet tract the engines being starved of air . Better cams open the valves further and a little longer so greater "window" of opportunity for the atmosphere (or turbo) to charge the cylinders . Exhaust porting and more valve area means you lose less of the thermal expansion driven exhaust gas velocity that drives our low restriction turbo through inadequate port/valve/manifold capacity . So shortish cams with safe extra lift , porting because the exhaust side needs all the help it can get , tuning because std its pretty soft and bent around emissions/noise/consumption and an exhaust manifold that works properly . My long term plan is headwork/Poncams/HKS cast manifold and the turbo you already know . With the real GT3071R yes , it needs the extra rotating assembly revs to do what the GT3076R turbos do airflow wise and even then its not the same effect . Compressor tip speed rises quickly with diametre so the centrifugal forces give a different effect . From the maps the mid trim GT wheels seem to give the best compromise of airflow vs adiabatic efficiency (heat rise) so thats where I try to be . As far as innertia with the GT30 turbine goes they are reasonably light for their vane area , possibly the greatest difference between it and the GT28 NS111 turbine is not only diametre (59.9mm vs 53.85mm) but blade count (10 vs 9) and trim size (84 vs 76) . This is why I think Garrett is very silly not giving us the 60mm OD version of the NS111 turbine , I put this to one of the Garrett engineers in the US once and he said exhaust flow would be less with a 60mm NS111 vs our 60mm GT30 UHP turbine . I still think there's a need for it but perhaps the economics of producing a dedicated series of turbine housings to support it are not worth Garretts effort if millions of GT30's are still going out their door . So untill they do or produce a less than 84T version of the GT30 UHP turbine we are stuck with the continental divide between it and GT28 turbines with only compressor and housing A/R juggling to help span the gap . Getting the engine itself as good as it can be pays off power wise but it goes a bit beyond cheap bolt ons . Nothing new here . The obvious solution if you want high Hp is to start out with the RB26 top and bottom end because it has more of the things needed out of the box . Even then porting and cams is still a big help . Always comes back to budget and effort/determination , cheers A .

Actually it was a GT3040R or as they are called nowdays GT3082R - exhaust side of GT30R with compressor section of a GT3582R . I've got 2c to spend but my thoughts are based on other peoples experiences not my own . Firstly reliable sources have proven that R33 RB25 DET heads/cams are already a bit lacking for 2.5 litres let alone 3 litres . Putting more cubic inches under these heads means port velocities are going to be higher at same crank revs or same when the larger one is at lower revs . It seems these heads are lacking exhaust port/valve flow expressed as a ratio to inlet port/valve flow . If they are limited on the exhaust side nothing you do to the inlet side will make any significant difference because its not the major restriction . Pumping losses mean power losses and reversion lowers the detonation threshold to the point where retarding the ignition timing (to save your pistons etc) kills off power production . The known methods of oncorking the top end are porting/maybe slightly larger exhaust valves , and better cam profiles . Slotting in a better direct fit exhaust cam would most likely wake it up but good results would also rely on the exhaust manifold / dump / cat / pipe and mufflers having adequate flow capacity . Actually before changing anything I'd be measuring exhaust manifold pressure just upstream of the turbo and comparing it to boost air pressure (at the compressor outlet) . Tapping into the exhaust here is the go because its the location where all of the engines exhaust gasses are collected and ducted into the exhaust housings inlet . Measuring air pressure at the compressor housings outlet is best because it takes into account any flow losses in the ducting/intercooler/throttlebody/inlet manifold etc . Losses in this area mean the turbo (turbine) is working harder to overcome flow losses and helping to create restriction on the exhaust side . My best guess is porting esp exhaust side and mild cams . It would be interesting to know what tuning strategies your tuner uses for off boost lower rev conditions ie adequate advance and clean mixtures . Also fuel octane ? Another thing that often gets overlooked is maximum boost vs maximum revs . You may find that dropping the boost a bit will allow the maximum revs to climb a bit , the lower boost pressure (and exhaust manifold or backpressure) means more revs for the same port velocities and maybe a little more advance with the lower max boost . Food for thought and 2c gone , cheers A .

The kindest thing anyone ever did to an Australian built Nissan was to throw all PBR/Girlock hydraulics as far away as possible . Irks me to say it but local content brake components are rubish compared to JDM bits . Rally fraternity hate PBR/Girlock cylinders because they are built to a price not to a standard . Thanks anyway cheers A .