M@&k

Not necessarily. While I thought it would make more power, it's always been the response that I've been mainly disappointed in. From the tweaking done so far, and in particular the last work (post #326) which didn't give any gain, I get the impression the compressor is basically maxed out for flow. If that's the case then I would think (or hope) the turbine housing isn't the limiting factor, and might be able to lower the boost threshold with the 0.63 housing without giving up much top end.

Have contacted Paul from streettotrack as per Wolverine's suggestion. If no joy there, and no other options, will try ATP. Any idea how much shipping would be?

They didn't realise there wasn't any available until they tried to fill my order. I got the impression they ship direct from Garrett Aus and don't hold stock themselves so they weren't aware there wasn't any stock in the country. He said they'd update their website now they know.

It sure is, and I tried to buy it through them, but they refunded my order saying they couldn't get any stock.

Having had the dump remade twice now to suit this Garrett housing, I'd be reluctant to change dump pattern again. I'd still keep the 0.82 housing in case of later upgrades (e.g. to HTA3073).

Funnily enough I've been thinking about the HTA3073... but not ready to spend on changing turbo's again just yet. I'm actually pretty happy with how it's going at the moment, just it's always been bugging me about what it might be like with the 0.63 housing, which it probably should have had from the beginning. Will see how I go sourcing a housing first. What style piping do you have? Goose neck over the cam covers? Or over the radiator shroud?

I've tried getting my hands on a 0.63 A/R IWG housing, but have been told no stock in Australia and Garrett is no longer manufacturing. I believe Disco mentioned this before too. Option now is to source from US, or second hand (annoyed I didn't get the one AngryRB was selling now). Only US supplier I really know of is ATP turbo. Any other suggestions?

Something which sits in the 50lb/min flow range would have been my second guess... Such a tease.

Let me guess. They're finally releasing the NS111 turbine in GT30 size?

I had a stainless 3" exhaust from turbo back made up with twin outlets. Cost just over a grand, and gave good gains on stock turbo (~185rwkW, pod, exhaust, nistune) while staying fairly quiet. One of the best mods bang for buck I've done.

Ok, so I've had some more work done to try and eliminate things which might be holding the GTX3067 back: * Dump pipe changed from split dump to bellmouth * Actuator changed from 8psi to 18psi * Replaced cat (which was an older model high flow) with a 100 cell high flow After the dyno run to check power etc, the sum effect of the above was... zero. No change in peak power, no improvement in boost threshold. Tuner said boost control is much better now, and that the dump pipe no longer gets as hot. His recommendation next is to change out the turn-flow intercooler, but I'd rather look at mods for better response first if anything.

Hey, I had to cut my reo and front bar for fitment. Was surprised actually, as I thought they were supposed to fit without cutting.

The forced induction quick reference guide on here has a few threads about the EMU. I think the point most are making is that you may be fine with the EMU, but your best chance of meeting your goal would be with a stand alone ECU.

There's also some companies offering bolt ons (exhaust side at least) for the GTX2860/63/67. Probably better off getting Hypergear to refurb a stock turbo, but throwing it out there for interest. SonicPerformance is doing turbo with housing: http://www.sonicperformance.com.au/Turbocharger-Upgrades/Nissan/Skyline-_dash_-Single-Turbo/pl.php Kudos has a kit on GTX2867 only: http://www.kudosmotorsports.com/catalog/garrett-turbocharger-kit-garrett-gtx2867r-nissan-skyline-r33-gts25t-r34-25gtt-rb25det-special-introductory-price-p-1459.html

Thanks gents. Will get in touch with George @ Venom. Point taken that there's no point worrying about legality between 200 or 100 cpsi given other mods won't pass anyway. Still have some minor concerns about getting annoyed by fuel smell. Will ask George.

Thanks John. All good points, but I'd rather avoid the smell if I can. I read in another thread that one guy was looking to change to higher cell count because he was getting annoyed with the fuel smell. I suspect I'd feel the same way. Is there much difference between 100 and 200 cpsi in terms of smell? Also agree bigger would look more legit

Peeps, many people with praises of 5" body Venom cats, but from what I understand they only come in 100cpsi. I'd prefer to get a 200cpsi version but they only do 4.5" body versions in that rating. Anyone had experience with those? For reference, I'd be looking at 3" in/out, 4.5" body (450 series). Power wise < 300 rwkW. Also, anyone heard of any issues with it not looking like a stock cat? I mean from avoiding yellow sticker perspective.

Fair enough. Sounds like an option and will put that on the table for discussion too. The other reason I've been thinking of getting the dump remade is to increase to 3.5". I realise it's probably overkill for what I have, but at least then I can rule out for sure as a possible restriction. Aaaand should be suitable if I go bigger later (e.g. GTX3071).

You may very well be right Disco. Exhaust was fitted when the car was pretty much stock, and before I knew much about what is needed. I imagine the current cat on there is pretty cheap. I was thinking of getting a 3.5" cat and reducing after, either just after the cat or towards the rear muffler... If I get it changed I figure might as well be a bit conservative to remove any doubts. What's the latest with yours anyway? Still sorting out injectors? I've never noticed any reductions in the pipe work anywhere. Tried looking in the rear muffler yesterday and didn't notice anything suspicious, but it's hard to tell as I have twin outlets on the back so can't look straight in. I'm certainly not against the idea, just that from many previous threads seems like a bellmouth dump is easier to get right. Given they'd have to patch up the hole where it currently merges, wonder if it wouldn't be easier to make from scratch anyway? At the end of the day I'll probably go with what Hyperdrive recommends. Just waiting for this bloody replacement wheel stud to be sorted so I can book in.

Thanks Mick. I'd be surprised if it's the stock cat as system was installed only a couple of years ago, but could very well be a low performance one. Looking at Venom cats; it's only $220 for a 3.5" 450 series, so will probably upgrade for piece of mind if nothing else. Regarding the intercooler, I remember you pointing out that was potentially an issue and the tuner agrees. Not sure what brand of cooler you pulled out but the Blitz SE one I have is 620 x 266 x 76 mm and piping seemed fairly large. I'm thinking I'll try with exhaust mods and stronger actuator first, and if I don't see a decent improvement then will consider Plazmaman intercooler kit as next step.

Have a couple of photos, one of cat (not sure if anyone can ID from pic), and one showing exhaust looking from rear muffler towards mid muffler. Have been doing some more research. Went back and had a look at Mick-o's results with the GTX3071 on 98. Comparing dyno plots; his 33 made more boost earlier, and more power everywhere. I appreciate there are differences in setups and whatnot, but seems like there's something not quite right with mine. Have overlay plot showing both which I could put up. Also for those interested found some interesting comments from a Garrett employee on designing exhausts to get the most from turbo engines. In summary, have as little back pressure as possible, try to have smooth expansion on outlet (as opposed to sudden increase), and properly designed split system is best, but well designed bellmouth is also good. Link here: http://www.tercelreference.com/tercel_info/turbo_exhaust_theory/turbo_exhaust_theory.html

I'll see if I can find out. For dump was thinking a 3.5" bellmouth and taper back to 3" at cat. Or maybe just get bigger cat at same time, I guess they're not that expensive in grand scheme of things.

Got in touch with Hyperdrive yesterday. Turns out there was some confusion about the turbo and he thought it was a T28 based turbo (e.g. GTX2867), which was why he wasn't surprised at power level. Once we clarified that it was a GTX30 with 0.82 housing he said he feels like it should be making significantly more and that he agrees the restriction is somewhere in the exhaust. Suggested next steps were a different dump pipe, larger open mouth as per Disco's comment above, and potentially check the cat to see if any restrictions there. I need to take the car back to get a wheel stud replaced, so will discuss plan of attack for new dump and if anything else worth changing at the same time.

I had my front rotors machined and it cost stuff all. I think about $60 for both. Certainly cheaper than buying new ones.

The split dump does strike me as being a suspect. The merge is very close to the turbine outlet (~100mm maybe), so I could imagine that turbulence generated might cause flow to get backed up in housing? Just to clarify, I'm not necessarily chasing more power. Just that if I can't get boost on well before 4,000rpm then might as well gone with a bigger turbo like GTX3071 or GT3076. It's 100% street driven at the moment, so what I'm really chasing is getting boost on earlier. Removing restrictions to make it more efficient and get the most out of it is also highly desirable. Tuner was, I believe, quite convinced that the turbine housing was the restriction so probably why he didn't suggest dropping the exhaust. I'm thinking of getting back in touch for further feedback from him given no one else seems to have found issue with this housing. Your thinking on turbine back pressure makes sense to me, but that could very well be because I want the issue to be something simple like restrictive dump pipe, lol. P.S. talking to a friend about this yesterday, and he said a restrictive dump sounds painful. Much laughter ensued.