Dale FZ1

And a simple Google search of "Garrett 700177-5018" lead to this link http://www.turbofast.com.au/GTseries.html which indicates it is a GT30 family turbocharger that uses a TO4S compressor (7 blades). That makes it a GT3076R There's really no science to those searches and you'd have found out long ago what your specs actually are. All that aside, do you actually have it fitted and running, and if so what do you think about it? Those specs support same/similar flow capacity as the 6 bladed GT3037R so I'm interested to hear how it goes in service.

Don't look at the compressor cover as being a determining factor for surge - that housing is pretty much a carrier for the air being forced in to the engine. The overall size/spec of the turbine, and the size/specification of the impeller within the comp housing are what I understand will dictate the general flow characteristics of the turbocharger. Force the compressor to turn fast/hard/early and you can get to the point of trying to push more air than the engine can ingest at certain load/speed ranges. That leads to the rapid oscillating column of air and the surge condition that gives the chuff/chuff / chirp/chirp noise. Changing from a 0.6 A/R to 0.7 A/R comp housing won't change a whole lot. That is a size ratio only, it does not describe an absolute size. When that number does become relevant is when he housings were designed within the same family. Then the bigger number indicates an ability to pass a larger air mass. An example of this would be the Ford XR6 GT3582 - 1.06 turbine, 0.50 compressor housings. I've seen people swap in a 0.70 comp cover to provide a bit more top end flow capacity. Also compare the 0.82 GT35 turbine housing, and it will flow less air mass than the 1.06 - but it will spin the turbine faster/earlier and give a different sort of response. Garrett and Borg Warner offer some very good tutorials to explain all of the above, with pictures to assist. Check Discopotato03's post and it's quite clear that just because something called a GT30 has a 0.70 A/R comp cover does not automatically mean it is a GT3082. It could well be a 7 bladed TO4S based GT3076 (which I think could not be legitimately called a GT3037 because the comp wheel does not belong to the 37 series). Point being you have to look at the signs, and source the CHRA spec sheets. Check out the number of blades, read the part number and cross reference it to what the manufacturer badged it as. The picture posted by DRD-OOF shows a 7 bladed comp wheel - that should be a fairly strong indicator as to what he has got. Technical differences aside, I think it would run pretty well. The main disadvantage that I see is lower compressor efficiency at high speeds that leads to higher inlet temps and a touch lower absolute power output from the engine.

Nic you might find that by welding up that slot in the collector divider that some stressors are introduced into the manifold. Could be counterproductive if it induces cracking, and you might find that the manifold requires facing after the heating/cooling of the weld process. Main point is that the gap is so small I wonder if it would produce any quantifiable result for the effort? A cast alloy elbow could be easily and cheaply welded to the compressor outlet., making for a bit tidier plumbing. I did so with my GT3037, no problems. The dump pipe flange might be better done with either 10mm or even 12mm plate. More metal to play with should = less movement/warping when you weld. I think the result will be better than using that cast V band outlet you see them sometimes come with. That casting does not look like a good flowing bit of gear, more suited to quick removal for servicing than anything. Work on a big diameter dump - 3.5 inch should fit in that area without much problem. Otherwise all good, keep us posted.

The HX35W (for wastegate ) designation indicates it is internally gated. Any pics I've seen show only one valve, however none of the BMW installations have complained of poor boost control that I've seen. Most often there has been a bit of biff n barge about whether the owner has got optimal performance from a truck turbo on a petrol engine, whether they should have spent more money and got something "better" etc. When I first became aware of these units, the biggest problem fitting them that I could determine was likely to be physical size - but evidently they require spacing much the same as the Garrett GT30 IW units.

Great work Nic - have a go. Should have some prospect of a driveable match to the 30DET, depending on impeller and housing specs. They seem so variable depending on original fitment. Make sure you post some pics up, and this thread should probably be moved into the 3 litre section eventually. If your housing is split pulse, then the spacer plate should be cut to accomodate that. You might be surprised what's available from the US, as there is a reasonable number of these things being installed on BMWs. Worth a quick search before asking someone to do a one-off, considering the labour costs associated, and also you're likely to get something laser cut and a very accurate match to the ports on manifold and turbine. For studs look to any half decent exhaust shop, truck parts supplies (maybe, but usually not many metric parts available), or an engine reconditioning workshop. Studs will just screw out, they run a conventional right hand thread. Use either a double lock nut, or vice grips clamped on nice and tight. Recommend spraying some WD40, Inox or Lanoline on the studs and leave it penetrate a day or two before having a go, and don't be that surprised if you have one break.

Definitely a juggling act on design, and retaining heat energy is something I'd consider important. No doubt most fabricated tubular type setups would suffer greater losses than cast ones, unless ceramic coated I guess. For the DIY blokes it's easy to disregard the cost of your own time when you've got the gear to do the work, but if having to pay a workshop yes, then a set of 6boost or similar manifolds starts to make good sense. Incidentally, are there any pics floating around of the 3>1 manifolds 6boost make for the RB26? Interested to see what the collector design looks like.

Can you find or post up any pics? Be interesting to see.

That's the way I read it too, thinking WTF?? Be interesting to have that clarified - I'm hoping his countless hours haven't been wasted by putting a thimble full of oil into the sump when it was going to need 4-5 litres?. Without all the plumbing hooked up the vid seemed to show a lot of noise coming from the inlet side (valves opening and closing), compressor inlet, and exhaust. Bit hard to listen for lifter noise over all that, but you'd nearly have to expect a bit of bleed-out if it has been sitting for some time. Then again, if it's got no/low oil pressure the noise might be something else.

Up to a certain power level, the basic engineering (shape and cross sectional area) should flow heaps, with the restrictions multiplying at each poorly matched junction (ie. head to manifold, manifold to turbo, turbo to dump). At the factory rated power level it wouldn’t be a problem, but proper finishing work = “free” power due to efficiency gains. I reckon you’re in the box seat Richard, with that Tomei gear at your disposal, but the guys who are cost-limited surely wouldn’t be too far behind with a set of properly finished stock cast items? Be interesting to see which way you go. I like the general way GTRSean went with port matching, but going off pics maybe needed some more work around the short side radius at the collector? Those sharp edges looked a bit abrupt. It’s great to see guys getting their hands dirty, learning what makes their car go, and sharing the experience.

Dan there is plenty already available here. I searched RB30 turbo under Forced Induction, and in 5 seconds this thread was found: http://www.skylinesaustralia.com/forums/Vl...p;hl=rb30+turbo Otherwise, a "highflow" does not affect the A/R of a housing. Nissan did not advertise the specifications of the RB25 series turbocharger, but search and you will find pictures and the sizes of the impellers. I know because I posted them up over 2 years ago The RB30 series turbo is not even slightly similar to the RB25. Check the link to the above thread. If you're not sure of the specifications of a turbo being advertised, ask who performed work on the thing, and contact that company directly. cheers

The GT3582 combined with a 0.82 housing on a RB30/25 should provide a great linear type of result – ie keeps on climbing with rpm. And looking at the overlays it does so, while the 2835 tends to flatten off across 120-150km/h with a bit of a kick at the end. I’d be chasing that smooth progressive delivery any day. If you want a searing mid-range rush, slip a 0.63 A/R housing onto that GT35. It’ll be anything but “boring”, but just don’t expect it to be easy to drive and achieve traction. Power-down is important if you want to go fast, as opposed to feel fast. Either way, looks like you’ve got a pretty good setup overall. The numbers are there, with room for more. I didn't notice any complaint about whether it goes fast, just the feel. Before you do anything, take it for a good run at the track (or strip), and let us know what you think then.

Why so? His plots overall look fairly typical for the type of development work undertaken. He explained some sort of problem and why the run was aborted, so still worth including for a general comparison. I'd say that the problem might be more likely rooted in a tock ECU going into the good old failsafe R&R. Demonstration of the lift in area under the curve aka power density aka average power might help people what to expect with their mods too. I'd rather look at torque plots though.

Never mind the sound, what's the difference like on the road?

Back to the original question posted, after deviating You may have been advised to go with a cam spec that was selected by the factory to work in a forced aspiration environment. Obviously that's with fuel consumption and emissions as big factors in the equation. Depending on your own requirements, changed overlap and ramp rates could be beneficial to power production/delivery especially when using a far more flow-efficient exhaust manifold and turbine setup. It would be interesting to check back-to-back the differences with a 20DET vs 25DE cam specs, but you may find the only real difference is fuel consumption due to blow-through of the inlet charge. Running the cam specs through the cam doctor program may be a big help to clarify likely outcomes and eliminate guesswork. However if you know what that head/cam setup has been capable of in another previous engine build, why deviate from the known?

The ceramic coated housing shown in the linked advert has the word Garrett cast into it, suggesting it is a genuine Garrett casting. The turbine/wastegate discharge area is not a "true" GT30 style design, but is very very similar to the GT25/28 style. All of which would make one suspect that there is an error in the description fields, perhaps regarding the A/R and the use of a T3 flange pattern. None of which means it couldn't be made to fit, but would want some further discussions with the seller before purchase so you end up with the product you think you're going to get. Garrett advertise a GT3071 using a T25 flanged housing, which in fact uses a slightly smaller 56.5mm turbine as per the HKS GT2835. The difference is that HKS actually cast theirs with a T3 mounting flange.

Not straying from the question posted, but the key difference between GT3082 and GT3582 is the rotor size in the turbine. 60mm vs 65mm OD at the inducer. The actual housing is basically the same but with some differences internally to deal with the larger rotor. It means that when you look at the rear of an assembled GT3582 vs GT3082 it will have a bigger hole to vent through. Bigger hole = bigger mass flow capacity as you would see from the flow maps available from Garrett. So for a given A/R eg. 1.06, the GT30 turbine will show a lower mass flow and efficiency than for a GT35 configured the same way. That is where your difference in "rated" power comes from. Depending on the overall goals and mechanical spec, it may be a better bet to go either with a GT3582 or a GT3076.

Got a couple of variables there you'd need to work on. What turbine A/R? What spec are the rods and rod bolts? The cam specs suggest pushing the effective rev range upwards - ie. moving the torque curve to the right. Turbine housing choice will move your torque curve around as well. Some who've used the GT3040 suggest it's great/useable/driveable, although the compressor flow is likely to outstrip the turbine flow capabilities. For the higher rpm and power capacity the cam specs suggest, perhaps chase a GT3582, and make sure the bottom end is built to withstand 8000rpm? I tend to think for some applications the XR6-T version is quite a decent match for a RB30DET. Possibly a bit of a soft delivery down lower, but the relative lack of turbine backpressure allows it to hold decent torque as revs rise. Be interesting to see a dyno sheet for mr rbman. Otherwise recommend putting the specs through a Cam Doctor review and see what the predicted results are

The best way to fast times is through light weight, but I think I understand what you're chasing. Seriously, I'd say the auto is actually your friend in getting a Stagea to move its lardy arse. The GT3076 / 0.8 A/R combination is by no means laggy or slow to respond either in part or full throttle use. Being a larger turbine than the stock RB25 setup though, it is best described as responding "differently". It puts a smile on your face every time the revs come up, because it's smooth, progressive, and there's a lot of it. With a bit of stall, I'd say few SS utes would hang with you at any stage if running that combination.

Ryan the one advantage you do have is an auto gearbox which allows revs to flare and mask any lower end torque deficiency @ 2-2500rpm. My setup (0.87 Pro S / GT3076) in the ECR33 didn’t exactly lack torque down there, but it just got progressively stronger as revs came up. More like a “proper” sports car. Autos really do make things easier for turbo matching because you’re not as conscious of driving into the effective torque range of your engine due to the fluid transmission coupling. The biggest difficulty with the 0.63 IW GT30 housing seems to be providing adequate boost control. You may have read the experiences of BHDave, and how he attempted to reach a happy medium in keeping things around 16-17psi. Mafia is the only other person I know of with a 0.63 housing, and he’s up around 20psi by choice. Evidently Mafia can hold that sort of boost without too much problem, so the tighter scroll must produce a flow dynamic where the wastegate can only vent so much and forces the rotating assembly to higher speed than targeted. I have driven Mafia’s 0.63 / GT3076 in isolation from my 0.87 setup and can offer this opinion in the drive: Sub 3500rpm the 0.63 felt more lively by a noticeable, but not massive degree. Also noticeable was the power tending to plateau/drop around 6500, where the bigger 0.87 doesn’t have any real feel of choking. The 0.63 didn’t feel snappy or difficult to drive, and the bigger 0.87 doesn’t feel laggy. It is best described as more linear/progressive, and the extra flow up top offers a broader rev range to use. With a heavy Stagea to lug around, having an engine that holds power through to 7500 may not be that useful however. If you could get any other owners out there with actual experience using the 0.63 IW GT30 combination, it would be great to get their opinion. BHDave indicated that the boost/engine response he got was fantastic, but the setup really needed an EW to control things properly. Incidentally I think you’d be doing very (VERY) well to hit 270awkW with a GT3071 0.63 combination, notwithstanding any other clever additions like Mafia has with water/meth. I'll reiterate that the power delivery on Mafia's car is not sudden/abrupt/light-switch like. It was definitely very streetable, and the only question mark relates to whether there is an inherent boost control issue with that 0.63 IW turbine spec. Summary: I like your thinking, but there are question marks over the 0.63 IW setup while the 0.82 IW has not earned any reputation other than good when matched to an RB25. If you can accept a power cap, then the smaller/faster turbine in a HKS GT-RS, or equivalent GT2871 high flow may well give a pretty good hit of bottom - mid range torque that a heavy wagon would need to feel nice on the road.

If you're running a 2 valve RB30, sounds like a Rajab style cast manifold? If so there would be quite a few VL boys with experience in this area. Most experiences here seem concentrated on RB20/25/26 DET / TT If you're looking to delete some coolant/heater lines around the manifold, probably ask yourself what you want to achieve, and you'll probably ge the answer whether to delete or retain. Colder climates and whether you can live with an engine that takes a bit longer to get to operating temps should be a part of the equation. I'd be sure there are good answers at boostcruisin.com Let us know how you go.

Get a 1 bar actuator and run the wastegate the HX35 is supplied with.

Unless the housing has been modified, there should be a number cast inside it, just near the mounting flange to indicate the A/R. Logic says that the -82 suffix would indicate a 0.82 housing, but they've put a model number of 3071 that does not appear true to type.

How has the post-mortem gone? ie I would want to know exactly what caused the failure since there had been no contact between piston : head. If the bearing is only gone for #1 I'd probably concentrate there first. Oil pressure may have been fine, but is there any chance of a blockage in that journal? Alternatively, maybe have a close inspection of the piston, rings, lands etc and look for evidence of knock. I'd think that detonation/knock serious and prolonged enough to cause bearing damage would have seen similar probs throughout and not confined to #1.

Results look good - you should be happy and I bet it drives great. Peak figure is in the right area for the spec, and you'd probably agree it gives nice progressive delivery. One thing I might suggest if you have the facilities and time, is to play around with timing under 4000rpm and see if you can fill out the curve in that area - you will feel the difference. By comparison I found mine made these outputs @ revs: 2800 - 100hp 3400 - 150hp 4000 - 265hp 4600 - 340hp Can't scan anything up at the moment, but main idea is that you probably have some untapped reserves down lower if prepared to play with the tune. Keep us posted with results of any more tuning and/or efforts on the track.

The phrases "power density", and "area under the curve" spring to mind when seeing the results. What were your goals when making the change?