discopotato03

My vote goes to inexpensive freshened NA RB30 bottom end . Bash the appropriate VG30 turbine housing on your std turbo for starters while the funds amass . Extra cubic inches will be the cheapest horses here . I reckon more power in a usable state of tune makes a better overall package . Only testing part is the head mod for the VCT oil and water passage . Everything else should go bolt plug .

Inside HKS's unique TO4Z compressor cover , as Doughboy said slightly different diffuser area . Shh ! Don't tell cruiseliner ... And a couple of extra pics why not . Note how the compressor backplate is iron and not aluminium , would not be surprised if Garrett used the same one from the old TO4S 60-1 turbo . Had they used an aluminium GT40 series backplate/cover they may have been able to get a similar effect diffuser wise . I suspect the TO4Z CHRA is just a comp wheel change to the BB P trim/60-1 cartridge with the cover reprofiled and the backplate machined out from ~ 76mm to ~ 84mm . Simple and cheap . Probably cheaper for HKS to get a custom comp cover with a larger diametre diffuser section made than to alter Garretts cartridge (backplate) . A little O/T but that GT37R cartridge with the Z's (TO4R) compressor could very likely out do the TO4Z .

Not 100% sure but don't C210's have Chapman Strut rear ends like a 240/260Z ? If so the DR30 semi trailing arm IRS won't fit . Off the top of my head DR30's had the shortest large diametre R200 CV half shafts so worth a look . The challenge will be getting them to bolt up to the C210's inner axle flanges ie not the diff end the other end . Need to see which axle bits (ie the bits supported by the wheel bearings) are available . Maybe some of the DR bits wil mix and match . Talk to Stu at SWR , they live and breath Z's . Cheers A .

T51R KAI . Cheers A .

Yep my bad , Garrett (typically) don't market a 52 compressor trim version of the GT3071R "WG" . I'll list these CHRA's and trims so you can tell whats what from the ID tag no's . 700177-0004 Turbine 90 Trim Compressor 56 Trim 700177-0003 Turbine 84 Trim Compressor 56 Trim 700177-0002 Turbine 84 Trim Compressor 52 Trim . Seems to be HKS option only 700177-0001 Turbine 84 Trim Compressor 48 Trim . Don't take this CHRA number as definite . HKS option only . I doubt the 90 trim turbine would be any more responsive than the 84 , more likely less so for the same gas flow . Going larger on turbine trim is a way of reducing flow restriction if its lacking . Keeping the same exducer or major turbine diameter generally means same shaft torque or drive power but less restriction in a larger wheel trim . I feel the better off the shelf solution (assumes Garrett will market propper IW GT30 exhaust housings as well) would be the real GT3071R probably in the real IW Garrett GT30 T3 flanged housing in .63 or .82 AR ratio . Actually the Pro S GT3037 housing would fit as well and have possibly better volute/nozzle shape and wastegate valve and vent path/dump pipe . This gets you the full sized 60mm 84 trim GT30 turbine in a propper GT30 exhaust housing driving the 71mm 56 trim (GT35 series) compressor . Personally I'd prefer Garrett make that GT30 turbine available in 78 trim and fit the 52 trim GT35 series compressor for best all round performance . It may struggle to reach 400Hp but the wide mid range and superior boost threshold would more than make up for it . If you want your engine to stay forever young you don't want to be forever at the redline . Cheers A .

ATP Turbo (US) advertising these IW housings for GT3076R and GT3582R . Also making this flange up for fabricated dump pipe . Cheers A .

Detonation is the greatest enemy , water injection is one way to keep combustion temperatures down to a level that the end gasses wont spontaneously ignite before the spark initiated burn gets to them . There is no guarantee that more boost will make more power . More airflow helps but greater exhaust restriction just creates more reversion . The unknown factor with that kind of water injection is equal water distribution between all six cylinders . It only takes one not getting enough water to detonate its piston to death . Also I would be a bit concerned about that injector before the intercooler because there's no way to tell if its filling up with water . When water vapor cools it condenses and could be winding up in the foot of the IC . Cheers A .

I think you'll find the smaller GT2835 Pro S housing is .68AR ratio and very likely intended for RB20's . Be a bit careful with GT2835 turbine specs because some are 84 trim and some are 90 trim . Compressors can be 48 or 52 or 56 trim so this can change results markedly . If the HKS .68 IW housings are gathering dust the RB20 fraternity should think about snapping them up cheaply and putting them on the otherwise useless Garrett GT3071R "WG" , the version with the 84 trim turbine and 52 trim compressor . Should be pretty responsive on an RB20 and run out of exhaust and airflow approaching ~ 400 Hp . I'll check up the trims and get back on that idea . Cheers A .

Honestly my opinon only - the GT2876R are dogs . I would sooner throw money away on those ridiculous "turbo zets" and use them for paper weights . Trying to force a 53.8mm turbine to drive a 76mm big trim compressor is just plain dumb . Look them up on the turbobygarrett website - they clearly state not for a performance application , I can't see any use for them in anything . Buy at your own risk - its your money/choise . Fours and sixes , can't really compare . As has been said the 2L six has ~ 330cc pots vs the 2L fours ~ 497cc pots . You are burning a greater mass of air and fuel in the four and venting a greater quantity of exhaust gas per cylinder - this makes a huge difference to low speed engine torque and the ability to excite large turbos . The RB20 has had many birthdays since it last saw any factory level development where the 4G63 has been a constant evolution that is still ongoing . They have come a long way with mechanicals and controls since the early VR4's . If there had been a 4 cylinder version of the RB26/30 it would have solved many arguments . Cheers A .

Very much so . Would show up the RB20's lack of torque in essentially low CR form . If Garrett get around to making the GT30 IW exhaust housings in .63AR ratio then the real GT3071R would be a much better thing . HKS's GT2835 Pro S could be Ok but expensive , 3071R a better thing IMO . As Joel mentioned IW exhaust housings need to be properly designed for high performance petrol applications . HKS's Pro S housings are probably the best for the GT30 turbines but not cheap . Truthfully the combination of compressor and turbine have a large say in potential wastegate problems . Its this holey grail of equal turbine inlet pressure and boost pressure that lets the waste gate regulate properly . Main problem with RB20's is that they're right on the cusp of GT28 and GT30 turbines flow wise . HKS seemed to nail it with their cropped version of the GT30 turbine but dropped the ball with compressor choise . Had they asked Garrett to make a GT30 turbine based cartridge with a smaller turbine trim ie 76-78 instead of the garden variety 84 trim the GT30 based turbos would be very responsive with small to mid trim 71mm or GT35 series compressors . I guess the expensive nature of the Pro S series turbos made HKS err towards the larger compressor trims , sort of more bucks for more power potential . I think they expect most RB20 people to be happy with GT28 turbine based turbos and the rest go with 2835's or GT3037's etc . It is possible to bitzer together a good turbo based on Garrett guts and HKS exhaust housing but not cost effective and O/T in this thread . Cheers A .

Sorry , sifted through this thread too quickly - I though I read full boost at 5-6000 and 2.8L . Online before first coffee ... Yep TO4Z the best big all rounder IMO . If money is an issue you could buy the Garrett cartridge and add the HKS turbine housing to it . Is the power number because you want it or a sales thing because T3 flanged manifolds are available and a large exhaust housing GT3540R would pull pretty well and be cheaper again . I'd be careful how much I spent on that car if its to change hands in the near future . Cheers A .

For that 5-6 full boost I'd be looking into Garretts GT4088R , these are available in Australia now and I think retail was ~ $2700 . The trick I'm told with them is to use the .72AR comp cover and not the smallest .85AR exhaust housing ie at least the .95 or 1.06 . Geoff Raicer from Full Race Motorsports in the US really likes them and makes good exhaust manifolds inc if I'm not wrong one for the RB26 . While the TO4Z's seem to work well I can't help thinking the P trim turbine is not up with the times , right diametre , right trim , dinosaur design . Cheers A .

Hi all , found an interesting read at a site called "Nissan Performance Magazine" which is a monthly online American blurb . If you search for that NPM site and click on the September edition , four articles down is the one that partly contains the article on the VQ35HR engine which seems to be the update to the current 350Z car engine . Towards the end it hints that there may be a 3.7L turbo version with Cosworth developed heads for the next GTR . A good read for Nissan Performance enthusiasts . Cheers Adrian .

Whats rock bottom cash price for four rims and I need proof that they are GENUINE GTR33 rims and not the heavier cast rogue copy . I'd like four pics of the individual rims inside and out . No cracks chips bends buckles accepted . If I'm to trek from Sin City to Melbourne I don't want a wild goose chase . Over to you , A .

Hard to find Pics . These are of the GT3788R or St3 version with the 52T 88mm compressor same as in GT4088R . Stage 1 and 2 have 50T and 56T 82mm compressors , stage 2 probably same as GT3540R and stage 1 not sure yet . Has possibilities , cheers A .

Nah , copper tops get a bit of salt and pepper rounds the hackles but no grey ! Yep , big for street RB25 but some like them that way - not for me to judge . Don't know about the 8000rpm bit , an RB25 in basic terms is just a more conventional or less competition oriented RB26 with 60 odd less cc's and one turbo . If it pulled up at 4000 that makes a 4000 rpm wide power range assuming you were going to go to 8 . No GT30's dont have the exhaust flow I'm after and unless the 52 comp trim GT3037 (HKS option only) was used the flow ratios are not good enough in my book . GT3540R is basically a scaled up GT3076R (real GT30R) . I'm not saying they're a bad thing is just I think there may be better (not off the shelf) options for a low boost setup on an RB31DET . The GT35 turbine is quite good though still Garretts older thinking of big or 84 trim . I'm going to hold out for (at this stage) the GT37R turbine which is a tad larger (72.5 vs 68mm) but in 78 trim rather than 84 . The 82mm 50 trim comp would be a doddle for such a turbine to drive so should make for good performance with very little exhaust restriction . I'm hoping to have a scaled up GT28RS or discopotato (that echo again) but for 3L rather than 2L . Bullocks Taters ? At this stage the turbine housing (GT37R) is huge and heavy but if it was assembled in a TO4Z bearing housing (basically same but clamps to exhaust housing instead of 4 bolt/ear type ie GT4088R) housing options could be TO4 or GT35 type . Will post some pics of elusive GT37R but OT in this string . Cheers A .

Hands strictly above the desk Joel !

You can find it and its maps at turbobygarrett.com . Click products/turbos and scroll down . I don't think it shows these housings yet - .63 , .82AR ratio IW GT35 turbine side . Cheers A .

I have seen it done to rally cars , lightweight means of stiffening up the shell .

Dale as a generalization the GT3540R should make similar power to one with a free floating housing (meaning non gated) unless the gate cannot pass enough exhaust gas to properly regulate turbine/compressor speed and boost rise . We now have all three AR sizes .63 .82 1.06 with IW so have some flexibility . The important thing to remember is that its not possible to run the smaller AR housings and expect the waste gate to make up the flow difference of a larger AR housing . Boost pressure is regulated by the waste gate actuator which uses a pressure signal from the compressor side not the turbine side . Exhaust manifold pressure/turbine inlet pressure/back pressure is dictated by firstly the turbine/housing and everything south of the turbine inlet . different sized exhaust housings are made to taylor turbine/compressor speed from the available exhaust gas velocity . It really is a juggle of turbine/housing size vs compressor size/capacity to pump air . If you use small AR exhaust housings on turbos with large high flowing compressors (GT3540R's one is capable of 70+ lbs airflow so 700+ Hp's worth of air) the higher exhaust gas velocity though the smaller volute passage brings the compressor up to positive air pressure type revs and if the engine is not running fast enough to swallow it you end up with either compressor surge or medocre low boost performance . Its my opinion only but a .63 housing on this turbo is too small given its air pumping capacity , if the .82 is too laggy its trying to tell you its too much turbo - or compressor anyway . If smaller trim compressors were available in this turbo it may just work . Another maybe is to use port shrouded compressor covers to avoid the surge issue . RB30DET's seem to handle the 1.06 ok and even the .82 for a roadie that does not use huge boost pressures . I hear people say that it works ok on RB26's as well though they are probably expected to lift their skirts at 4000+ rpm . I guess a serious track Rb25 with gearing etc to suit could use a .82 version . Gary and others have said that even GT3076R's can be a bit much on a daily driven RB25DET so the GT3540R being larger could be expected to have a higher boost threshold . This is normal when comparing a 500 to a 700Hp capable turbocharger . Power numbers are impossible to quote because the same turbo will give vastly different results on a real race engine compared to the production version it was based on . You can base turbo power potential off the maximum airflow it can efficiently pump (this is usually expressed as pounds per minute) though exhaust flow and turbine efficiency is just as important . Out of here now , need some sleep (I know how Roy feels) . Cheers A .

Sometimes auto bits outlets and Hardware stores carry this kind of thing . Cheers A .

Hi all , I got to look at a couple of these this afternoon - yep .63 and .82AR ratio . The Garrett part numbers for the housings themselves (according to the packaging) is 771300-5 for the .82 and 771300-6 for the .63 . The waste gate flat valve looks to be the same size as the IW GT28 housings and there is room for a larger disc as well . Doing a "high flow" on this valve is common practise on souped up XR6T's so no reason why these could not be modified the same way . BUT - always that but - the greater the area of the disc the more area exhaust manifold gasses under pressure have to work on to try and force it open . I kid you not and don't laugh , I've seen people using what looked like old bed springs trying to keep this valve shut . The rule is if you run high boost pressure do everything you can to have the exhaust manifold pressure down somewhere near inlet manifold pressure . You don't need massive exhaust manifold pressure to drive the turbine just sufficient gas velocity by thermal expansion . Back to those housings , Brett at GCG has I think five of each AR size ATM so be quick if you need one soon . Had I been better organised I would have had some pics but no doubt they'll turn up . Cheers Adrian .

Yes very interesting , hope they are available in quantity ! Dale the CHRA number would be the same for any cartridge with the same comp/turbine so its the complete assembly or unit number you want . Something worth noting is the part number stamped on the side of the exhaust housings mounting flange in the second shot . This would almost certainly be the turbine housings part number . What I want to know is can these housings be grafted onto the GT37R cartridges because they have the potential to be better than the GT3540R cartridge for the larger/est RB - just need a suitable exhaust housing . Cheers A .

Yes I agree with Slide . I think he is telling you that the RB25 and VG30 versions use a larger diameter compressor wheel with a matching larger compressor cover . These would accept 70-71mm compressor wheels more easily than the covers on the smaller RB20 type compressors . This makes the RB25's turbo (housings really) a bit more flexible with compressor options . So in other words unless you want to stick with 60mm diametre compressor wheels ie dinosaur T3 wheels or a GT28BB cartridge the RB25 is the go .

Yes the flange on the exit side of the HKS is slightly more compact than the Garrett one but then compact is good in most engine bays . Being in the US means that you could probably track down a suitable HKS housing from one of the HKS dealers - can buy separate . The T3 housing will have issues with the GT30 turbine because it was designed many years ago to suit low tip height T3 turbines . The turbine and housing type really are a matching set designed to work with each other . Cheers A .