Looks Like Garrett Slipped Another Gtx30 Variant In .

[M@&k]

Haven't had a heat shield on since the exhaust was fitted a couple of years ago. Asked to see if they could fit one this time around but they couldn't find one in decent condition. Was something to revisit when I take it back for next checkup.

I actually quite liked how they kept the solenoid in the stock position, but I see your point.

[Ben C34]

Haven't had a heat shield on since the exhaust was fitted a couple of years ago. Asked to see if they could fit one this time around but they couldn't find one in decent condition. Was something to revisit when I take it back for next checkup.

I actually quite liked how they kept the solenoid in the stock position, but I see your point.

With the solenoid the empty port would probably get cop attention. Perhaps just screw a fitting in to and run a hose off somewhere to disguise it.

Acl make heat shielding material. Pretty easy to work with and gives great results.

[Lithium]

I've missed most of the updates, been very very busy - but looks really good. Did you get a chance to take it out for a drive over the weekend?

[M@&k]

Yeah I did go for a decent drive on Saturday. In higher gears it's making positive pressure in low 2k rpm, but doesn't really get up and boogy until high 3s. The new power band will take me some time to get used to. I noticed it drop off boost when shifting from 2nd to 3rd, but I strongly suspect this was due to me short shifting which is probably a habit picked up from driving the stock setup. I still need to find some quiet roads where I can more safely have a proper crack.

While I'm loving the power when it's on, I still feel like it would be nice if it came on maybe 500rpm earlier so the extra power is in easy reach on the street rather than being a stretch.

As I said I definitely still need to spend more time getting used to it first. Not as crazy as 90% of the setups on SAU but a long way from the basically stock car I'm used to. If I don't get used to it in a couple of months I may consider changing to the 0.63 housing. I assume that wouldn't be a majorly expensive undertaking.

[Lithium]

That really a bit surprising, I did suggest earlier that I could see the potential for the mix of small wheel which needs rpm and big a/r housing making a bit lazier than it could be but still - that sounds at best no better than my GT3076R which at face value doesn't seem right though perhaps spinning up a smaller compressor really makes that much difference?

To put into perspective - here is my old 0.82a/r GT3076R on what should be a pretty equivalent setup to yours:

... internally gated, stock manifolds and motor etc. Your car clearly is going to be performing well - I don't doubt it'd be fun as it is, but I definitely want to try and work out what's going on as amongst other things I was one of the people supporting this choice and was expecting more impressive response (I was also banking on the 0.63- but still) and I've not really gone wrong in the past.

I'd like to think you shouldn't need to do anything else other than the 0.63a/r housing to change it into a different car, but *normally* it doesn't make that much of a difference. Maybe in this case it could be more about shaft speed than inertia - the whole exhaust fed system makes a compounding effect, so perhaps it might fire up much quicker relatively speaking (to a 76mm compressor) with the lower inertia when the exhaust speed goes up, but maybe not? I am gonna do some pondering.

[Ben C34]

Goes to show the whole turbo sizing mystery is a dark art filled with mystery

The turbo is a very mysterious and powerful device

...and it's mystery is only exceeded by it's power.

Edited July 7, 2014 by Ben C34

[AngryRB]

How hard would it be to put a Hta compressor wheel on rather than change the housing?

She might break free of the dyno then..

[Mick_o]

It'd be as hard as removing the turbo and sending it to Mr Robert at FP I actually think the HTA68 wheel would liven things up a bit.. But I think the HTA73 wheel would be much nicer! Works damn fine on my Evo lol!

How hard would it be to put a Hta compressor wheel on rather than change the housing?She might break free of the dyno then..

[discopotato03]

I don't agree with your viewpoint but at the end of the day engineers and manufactures have to try everything real world to get a real result , then move things around a little to dial in their desired result .

I think in this case the consensus view was to treat the 0.63 housing with suspicion because they don't always suit peoples likes on GT30s with larger compressors and housings .

Units like GTX3071Rs and GT/X 3076Rs are going to have higher pumping capacities and higher tips speeds and the 0.63 housing can be a bit marginal on flow once those compressors are run towards their limits .

It might be interesting to compare the lower compressor flow rates and wheel speeds to see how the GTX67 compressor compares .

To my way of thinking if your getting positive pressure at low revs in high gears that sez that greater throttle opening is probably sending more exhaust pulse energy down the line to the turbine and getting it going . The same engine revs in lower gears divides the engine load by the gear ratio reductions so the throttle opening is often less meaning throttle dampened exhaust pulse energy .

A smaller AR turbine housing will increase the exhaust gas velocity through the turbine blades everywhere and in theory spin the turbine faster lowering the boost threshold across the throttle/load/rev range .

I'm sure if you changed to a 0.63AR IW turbine housing (direct exchange) and liked it the 0.82 one would be easy to sell because these housings are a considerable part of a complete turbos price . Or , if you decided later to use a larger GT30 turbo it's cheaper to buy and add your own housing .

Just on this when last at GCG they told me Garrett is keen to ditch these IW GT30/35 T3 housings because larger markets are opting for external gates and V band fittings .

Don't know how long stock will last so maybe check availability with your supplier , cheers A .

[Lithium]

Agreed that the HTA68 would probably be more interesting on an RB25 with a GT30 hotside, but I'm not at this stage convinced that the GTX-67mm is (solely?) to blame for the response. Again not totally sure what is, I do wish it was the .63 housing - however.

I don't agree with your viewpoint but at the end of the day engineers and manufactures have to try everything real world to get a real result , then move things around a little to dial in their desired result .

Not sure who you are disagreeing with here, but have to assume it's not me because it looks like our overall thoughts are more or less the same.

[AngryRB]

on the dyno graph it looks like it hit a wall around 4000rpm then regained its path, maybe its because of the boost curve or the VCT? still a decent bottem end though with that lowish boost and 98. More time spent fine tuning it and raising some boost in the right places would probably bring 200kw plus at that 4000rpm point and give it a different feeling to drive again, unless it was deliberately held back due to knock levels at that point.

Edited July 8, 2014 by AngryRB

[Dale FZ1]

I'd suggested early on from the advertised performance map that this 67mm compressor needed higher rotational speeds to do its thing, and didn't buy the theorising about windmilling contributing to lower boost thresholds.

Mick's views that the tight bends in cooler piping costing hp and some response hold weight, and there may be easily available gains by making changes there.

The fact at this point remains this 0.82 turbine combination is making things happen in the same engine rpm range as other GT30s using bigger compressors pumping at lower speeds.

Leads me to conclude that advice I received a few years back was correct. Turbine choice/spec has the biggest bearing on turbocharger response and engine response. The compressor is the dumb device being driven by the turbine, and if it doesn't spin fast enough, early enough then it won't do the business.

I'd have some concerns whether the 0.63 IW housing is the best choice from a boost control standpoint, but if the targeted boost is going to be 18+psi that might be academic only.

[Mick_o]

Yeah I don't think the 67mm GTX has given its all yet and with the current setup a Hta wouldn't help anything. As Dale said I am willing to bet money if you changed the cross flow cooler and ran some less restrictive pipework. It'd change the game (provided your exhaust isn't a restriction)

I saw a result with the same setup my 33 had and it only went 258kw from memory I looked over his setup and suggested ditching the cross flow cooler and some new pipework. He did he threw a Plazmaman cooler and pipework in and made 280kw on the same dyno with a slight touch up of the tune.

[Mick_o]

I think intercooler pipework is often overlooked alot I've learnt this 1st hand with my skyline the custom work I done to my car shortening pipes and removing bends helped no end to me achieve the result I did. Even more so with my evo! Some of the 1st basic mods on an evo are to ditch the factory restrictive pipework. Evos are quite a well sorted package from factory and when you consider they are over a decade newer than most 33's. They learnt alot in than time period getting stuff right. But when you think about it if a decade later the pipework is holding things back, imagine how much of a resriction the old skyline stuff would be?

[Manuel Kasko]

What type of pipe work can you run an a R33 gtst though to increase flow?

I always thought that the hole under the battery tray is actually a defect. I can't see a way you could improve the pipe work without doing this and running it over the front of the engine bay.

[Mick_o]

https://www.plazmaman.com/shop_itemdetail.php?itemid=153&cate=73

This is basically what I done with my car Dan..

Probably the shortest best run you can buy in kit form.

[wolverine]

I have >270rwkw out of a Plazmaman return flow on the yellow pig so I am not convinced that a Blitz FMIC is the issue.

I am no fan of split dumps either but I doubt this is having a significant negative effect.

I would love to see the exhaust dropped next time it is tuned to rule out any restriction there...just in case.

Regardless of all the above speculation I would pressurise the intake to double check there are no leaks (ahem Mick )

To me it looks like most other 0.82 Garrett GT30 turbine seem to deliver...just like Dale says this is the most likely thing that has determined the final result.

[Manuel Kasko]

Cheers Mick

Looks a lot better than most of the kits people run from eBay etc which come right across the front of the bay and over the fan etc.

So you think this would make a noticeable difference to a blitz return flow setup that uses stock return?

It still requires the cut under the battery tray which may or may not be a defect. But at this may just be misinformation that I have read.

[M@&k]

That Plazmaman kit is exactly what I was originally considering, but was talked out of it.

Daniel, cutting into the chassis is almost certainly defectable, but I understand it is possible to get it engineered so long as your car isn't fitted with an airbag. If it does have an airbag stock then you run into big trouble.

While I agree this type of piping would improve overall efficiency, I feel like the best bang for buck would be to change the turbine housing. I expect this would have the biggest effect on response and wouldn't take much spanner work to change and just a touch up to the tune. I guess a higher rated actuator at the same time might be a good option too.

Would make an interesting back to back, but for now I need to get some more km's in. Hardly had a chance to drive it. Might see if I can get some video clips similar to Lith's showing response in different gears.

[scotty nm35]

Cheers Mick

Looks a lot better than most of the kits people run from eBay etc which come right across the front of the bay and over the fan etc.

So you think this would make a noticeable difference to a blitz return flow setup that uses stock return?

It still requires the cut under the battery tray which may or may not be a defect. But at this may just be misinformation that I have read.

The blitz kit is fine, it will easily support 400kw. I agree there is always a better result with smoother bends, but the factory stuff in the engine bay won't hold you back that much.

Cutting the battery tray is just stupid these days, as I said there are other options if going cross flow.