discopotato03

When you say shim on bucket I gather you mean shim on top of the bucket like some Toyota twin cams ie 4AGE . Makes life easier than under the bucket and the labour intensive drama of cams in/out to set clearances . Cheers A .

Interesting , What does a 1UZ live in ? Landmine er Landcruiser ?

With parallel twins you need to work on the exhaust flow rate of half the number of cylinders ie 3 cylinder 1300cc for each turbo because thats what feeds them . Maybe you should consider the two RB20 Hitachi cartridges in the original RB 26's turbo housings and manifolds , at least it should then bolt together and look a bit more um .... functional . Cheers A .

Do I remember SK or someone saying there was a suitable piston ie 4AGZE that completes the package , are any piston mods necessary or std Toyota and at what cost ? Which head gasket ? Cheers A .

If I had the time/resources/interest to develop such a thing it would have two plenums 123-456 fed by two throttle valves . I believe it would stand a much better chance of even distribution over each set of three cylinders and halve the reversion problems . The 153624 order would draw from front back front back etc plenums . Engines such as the four cam twin plenum VG30 do it a bit like that though if memory serves me correctly they have a throttled balance pipe as well . The Porsche flat sixes have had separate plenums from the beginning . Difficult to package on a straight six Skyline but sometimes these things work . Nissan dualled everything else on the RB26 except the plenum and intercooler so who's will be the first ? Cheers A .

No probs and good points raised . With the bit about the wastegate and turbine acceleration the gate should not be open at all as the turbo "spools up" . The wastegate is opened normally by compressor outlet pressure to give constant boost pressure as the speed and air flow rate rises . The whole thing about well matched turbos is having low exhaust restriction so we can develop more power from less or sane boost levels . You are quite right saying that turbine flow maps are all about maximums in flow and pressure but they are the critical points with turbines . When your turbocharger is windmilling , light throttle cruise no positive inlet manifold pressure , turbine efficiency is not terribly important . Exhaust flow rate is important and minimum or no restriction is very important . The manufacturers are only interested in what happens when it starts to boost . Most current turbochargers owe their development to the world of Diesels with good reason . Next time your on the highway near an interstate semi listen to the way they load up and the turbo sound . They are designed to work over a narrow rev range (engine) and the turbo can stay on full boost all day and all night . They are designed to be efficient at full boost and survive it for long periods of time . The locomotive diesels we operate literally run flat out at 150kpa boost pressure for hours churning out 3000 Kw . Transient response is not just about spooling a turbo up from low but rising engine revs (and exhaust gas flow) . You could be rolling down a hill doing 4000 rpm with the throttle shut and turbo only idling (very little exhaust gas flow) and boot it at the foot of the next hill , if the turbo had heavy internals the transient response can be not real flash because of the innertia to be overcome . Very rapid transitions can make a modern turbo engine package feel like a larger NA engine torque wise . Cheers Adrian .

Does the RB30ET cast dump pipe fit , should not be too hard to find . 60 trim T3 with a .63 rear housing may be a bit laggy on an RB20 , if so the .48 turbine housing off a Z18 or late FJ20 may help . Actually I would have put the exhaust housing off a dead RB25 turbo on the original RB20 turbo or the complete RB25 turbocharger . The problem is hooking everything up around a non native style turbo - labour = expense . T3's in non stand apps really is scraping the bottom of the barrel technology wise - 30 year old stuff .

That turbo (GT32) is a problem , it has a twin entry or "split pulsed" exhaust housing and the integral gate looks to only vent one of the two entry passages . As I said the real GT30R (with the 6 full and splitter blades BCI-18 family GT37 compressor) goes under turbo number 700382-12 or -11 for the 56 trim compressor . The cartridge or CHRA no is 700177-0007 . For the 52 trim version (I have only ever seen this on HKS optioned GT3037's) the turbo number is 700382-9 or -10 . The cartridge or CHRA number is 700177-0006 . Easy rule of thumb is normally 76.2mm GT37 series compressors come in T04E type compressor covers whereas the dinosaur 7 bladed (full and spliter) TS04 wheels usually live in .70 ARR TS04 covers which normally have 2.5" outlet and 4" inlet . The stand out is the Ford BA XR6's GT3540R which has an 82mm GT40 compressor in a .50 ARR T04E cover , the integral gate and FORD cast into the exhaust housing identify's that one if its not been altered by sticky fingers ! Cheers A .

StockyMcStock , can you ask him nicely for a picture of the XR6's turbo's Garrett ID plate or tag please . That 370 RWHP on an RB30 sounds the ticket particularly with 13.5 pounds boost pressure (did I read it right) . Thanks Adrian .

I would be looking for a good 2nd hand open diff in the right ratio and swaping the rebuilt hemisphere . Differentials rarely chew out the crownwheel and pinion teeth . You could open it up and check the teeth (backplate off) . Its probable that the backlash settings (washers on the outer sides of the carrier bearing outer races) is not set correctly which gives the clonk noise between drive and overrun . R200's are pretty tough diffs and it takes huge abuse or no oil to really kill them . The hardest thing to do with any diff is to set the pinion height in the housing , without factory tools and lots of hours assembling and disassembling changing the ratio is very difficult . Cheers A .

Thanks again . I also noted the slight offset in the compressor outlet . Would it be pushing the friendship to see the compressor wheel with the housing removed . Cheers A .

Thank you very much great feed back . Pics of the turbine end on and from the side would be great . While I'm here the numbers on the ID plate would be interesting , my list shows the cartridge or CHRA number as 700177-0003 for th 84 trim turbine and 56 trim compressor . The turbine should merasure 51.6 by 56.6mm (84T) and 53.6 by 56.6mm for 90 trim . A couple of things to note , HUGE vent for the waste gate (2835) and the model specific outlet flange pattern on the HKS 2530 to suit the RB20/25 dump pipe . The thing I'm really curious to know is if the HKS GT3037 Pro S has a divider between the turbine outlet and the waste gate vent hole as the turbine outlet is larger again and there's not much meat with the 2835 housing . Cheers and thanks A .

I'm no expert engine builder but I have seen gudgeon pins walk out and run on the cylinder walls . Generally the locating circlip (sp ?) has failed and no longer locates the gudgeon pin . I'm told Spiral locks never fail if fitted properly , may be worth a look . Cheers A .

Variations in the GT30R series . Basically there are two turbine variations , The first is the std GT30 turbine , the second is the cropped compromise . Compressors come from two families , the BCI-18 series which are the propper GT series and CAD (computer aided design) developed with more modern fluid dynamics technology . The second are the old dinosaur T04S types developed in the middle 70's . Cost difference is due to late designs costing money to develop and like anything that gives superior performance - you pay a premium . Garrett is a business after all . If you want superior results you have to pay for them , same with oil tyres etc Part no's , these are to note the many variations available for Garrett and everybody else . Don't let the sharks tell you they're all the same because they're not , they have different characteristics to suit different applications . Do some research . Cheers A .

500 HP daily and 600 for dyno runs and response over power - from 2700cc's . The Americans have played with a system of a centrifugal supercharger blowing through an exhaust driven turbocharger with good results but it needs a bit of thought put into by pass systems . I don't know if there's any other way of making it streetable without more capacity - I would have given serious thought to the RB30/31 conversion as I'm told 600HP is a walk in the park with suitable hardware . The GT40R would do well on a street driven RB31 Dyno Queen . These are not common yet but will get some details . Cheers A .

I would use the S15 differential complete in an R32 if it fitted . I can't think of any logical reason why Nissan would change the pinion offset for the late R200's . I think you'll find the late ones are short because of the cradle type multilink IRS vs the semi trailing arm IRS with its cross member . Obviously pinion support on the short version is not lacking if GTS25T / GTT and GTR performance is anything to go by . I have a DR30RS 3.9 LSD with a good centre and wanted to know if it fitted the short type R200 . The 3.692 (3.7) would work well with the 3100cc's low down torque . Cheers A .

Did some research and found that the late short pinion R200's use the same carrier dimensions as the early ones . The crown wheel bolts may be larger but this is easy to fix . They can be drilled as the crown wheel locates on its inner bore not the bolts themselves . Lots of options ie Torson 3.692 (manual S15) for RB31DET in R32 . Cheers A .

At long last pictures of the Pro S integrally gated T3 flanged exhaust housing . Can we please have heaps of pics of this section particularly from the back . Note the wide channel exhaust escape path from the flap valve . Would it be possible to have some pics of it with the valve open and a light shone in the mounting flange hole . Bravo , thanks A .

If the cartridge is horizontal meaning the water fittings are at the same height its not important . If one is slightly higher I would make it the outlet or hot water return to the cooling system as it will probably thermosyphon better when the engine is shut down . The critical thing with water cooling is having the plumping rising to , through and beyond the turbo to preferably the highest point in the cooling system . Do not make the turbo a high point as steam bubbles will get trapped and where there's no water there's no cooling . When the engine is shut down at running temperature the water pump stops and there is no forced feed . The turbos exhaust housing and manifold being iron can store a lot of heat energy , when water cooled the water will boil in the bearing housing and the steam bubbles rise out the higher pipe and return to the radiator top tank preferably . The boiling water is replaced by cooler water from the lower pipe and on it goes - thermosyphoning . On the Bluebird I had with the other FJ20 the turbo would gurgle away for about 2-3 minites , you could feel the bubbles rattle their way up the top pipe into the head behind the thermostat and via the top hose to the radiator and overflow tank . Obviously this short but critical time is when the turbo is hot enough to bake the oil to the bearings and damage them over time . Note that the manufacturers only tend to use 5/16" or 8mm plumbing as it provides adequate water flow . Cheers A .

What about one off a Z32 or even an MR30 , if the resistance is right the old stuff is common and cheap . In fact if you got one with its loom plug it would be neat and easily replaced if need be . Cheers A

Dale FZ1 , if you divide the turbine major diametre into the compressor major diametre you get a more workable number ie GT28RS/GT2860RS is 53.8 divide 60.1 = .8952 x 100 = 89.52 . In other words the turbine major diametre is 89.5% of the compressor major diametre . For the real GT3071R (CHRA no 700177-23) substitute the numbers 60 and 71.1 to get 84.4% . The GT30R is 78.7% and the GT3040R is 73.2% - I think you get the picture . With that mention of NS111 and GT30UHP its really a combination of turbine AND native exhaust housing that makes them work correctly . In my opinion the good turbos generate a few pounds of boost at very low revs and don't do the massive torque rush when they spool up . I think its a case of low resistance to exhaust flow that does not go through the roof when the compressor gets up to speed . It also tends to be a bit more traction friendly and easier to drive close to the limit of adhesion . Cheers A .

OOPSH .

Thanks , from what I could find 200SX S15 manuals use a 3.692 and mabe some US spec KA24 powered 240SX's . The S15 torsen may be nice for a road car . Still looking into ratio of six speed R34GTT . Cheers A .

Hi cubes , so S13 short nose R200 is 3.9 to 1 . Can I assume that all the late R200's are the same except for ratio and the GTR's larger half shafts . I found a few links to people who put short nose diffs into early cars and with a bit of fabrication its not too hard . I've wondered if its possible to do this the other way round (long nose in R32) to get a 3.7 under its butt . Do any of the auto S13/14/15 R32/33/34 used a 3.7 / 3.9 . What did Nissan use on the six speed R34 GTT's ? Cheers A .

LOL no but I was a Fitter/Machinist till I worked out it didn't pay too well . Cheers A .