Looks Like Garrett Slipped Another Gtx30 Variant In .

[discopotato03]

"A bit like putting an RB25 in a Supra" . Nope that bit wasn't V8 .

I wouldn't think a 6.2 or 7 litre Ch-evvy done right would need turbo/s in a lightish car .

A .

[Lithium]

What I meant by that comment is they put a Toyota V8 into a Nissan chassis when the Nissan brand has far better and easier to acquire V8s - for the sake of purity as well as performance I thought it was a weird way to go. Agreed with a 6.2+ litre V8 not needing turbos to get the performance, and they probably fit nicer... but turbo V8s definitely tickle my ticklish bits and the idea makes me happy.

[GTScotT]

"A bit like putting an RB25 in a Supra" . Nope that bit wasn't V8 .

I wouldn't think a 6.2 or 7 litre Ch-evvy done right would need turbo/s in a lightish car .

A .

oh right. this didn't make sense to me as a supra comes with an equally laid out motor.

anyway, doesn't matter.

[M@&k]

Apologies for thread bump, but was interested in more opinions on this turbo.

In particular I was interested in thoughts on how the GTX67 compressor might go with the cropped GT30 turbine. For arguments sake let's assume it's in a decent T3 turbine housing (e.g. HKS Pro S style).

So, any thoughts on performance of GTX3067 vs. GTX3067-WG on RB25?

[discopotato03]

Simple enough because it's a turbine change but would the result be better than a standard GTX3067R ? Those HKS Pro S turbine housings may not be too easy to get and they lock you into a unique dump flange .

I think in this case I'd leave the std GT30 turbine in place because you can always use larger comp size GT30 cartridges in the existing turbine housing ie a GT3076R . Even if you went up in T hsg size as least the dump is reusable if it's the GT30 style IW one .

A .

[M@&k]

Hmm, yeah good point Disco. I guess I'm kind of hung up on the HKS GT2835 Pro S. That's the turbo I really want, but prices (new) are just stupid. Have been wondering if there is a way to replicate it for a decent price. I guess the stuffing around isn't worth it given all the off the shelf options available.

[discopotato03]

Best guess is similar results . The Garrett has a tad more turbine in a tad smaller AR housing so the result is probably quite similar .

If Mafia got good spooling from a 0.63 AR GT3076R 56T then it's hard to imagine a smaller comp wheel and housing update doing worse .

I think flying results with a 0.68 AR 2835 Pro S is a bit under 300 wheel wasps and that's about where the GTX67s map points to IMO .

Probably comes down to money - if you could get a 2nd hand runner 2835 Pro kit for the right money and you like them do it . If not consider a GTX3067R . I can't promise ~ 300 out of it but gut feeling is possibly 280-290 on ethanol if everything is spec'd and working well . It should be responsive too but so far no ones had one on a 2-2.5L inline six AFAIK .

Can you live with almost 300 at the bags ?

A .

[M@&k]

Yep that's basically the target. Will be running 98, so figured 260rwkW would be absolute minimum I would be happy with (otherwise might as well get GT-RS?), although really would be aiming for 270-ish. Not interested in engine rebuild just yet, so sub 300kW is the plan.

First big upgrade for me, so having trouble pulling the trigger. Pretty confident this turbo will do what I want. Just a bit paranoid about buyers remorse later, haha.

Anyway, I guess that's the nature of these things. Certainly wouldn't be anywhere close to a semi-educated decision without the loads of info on SAU.

[discopotato03]

Well there's a few ways to look at that turbo and the biggie IMO is where to go if it juuuust falls short of expectation .

The positives are that it's more compact on the compressor housing side so may not need the T3 spacer to clear the exhaust manifold . Compact means less lethal looking to hostile eyes ...

The negatives are that it's a dead end because it's unlikely bigger turbine housings would do much for it . To go further means another turbo and quite likely another turbine housing . My thoughts only but I think Garrett reached the GTX wheel flow limit for that T04B comp housing with their 67mm wheel . The next size up is the T04E housing on the GT3076R and GTX3071R/76R . AFAIK the GT3076R 52T is the mild option for the T04E though there may not be a big difference between it and the 56T version . Whatever the difference - it should be on the right side of its bigger brother spool wise and even more so compared to a GTX3071R . It's what I have and my hopes are that it will be reasonable spool wise for a turbo that can crack 300 wheel wasps with not much left in it .

Only you can know what you want to end up with power wise and the thing to avoid is buying two turbos to get it right . High ethanol content fuels will help you get the best out of a turbo if it's marginal size wise so that's a possible option too - provided you can get it locally .

Lastly you can try too hard for a fast spooling turbo and it can be challenging to work around if its a bit limiting on the hot side .

Over to you , cheers A .

[M@&k]

It should fit without a spacer I believe. I see the GTX3067R as being roughly the same flow wise as the GT3071R, but hopefully with better spool to improve the mid range a bit.

What's the latest on your install? Pretty keen to see results.

[wolverine]

Why do you think the spool will be better? The GTX wheels work at higher boost pressures which seems to make them relatively docile for transient response in my limited experience.

[M@&k]

I figured the smaller compressor wheel would take less effort to spin up. The 3067 still has its efficiency island peak at moderate boost pressures (e.g. 2 to 2.5 pressure ratio). So not hugely dissimillar from the GT3071 I would have thought?

[discopotato03]

I'm nearly out of rear brakes ATM so that's taking priority .

A GTX3067R would be a bit more compact than a GT3071R .

I don't want to start a war but it seems that HKS got the best all round results with the 71mm GT compressors and they did it with the cropped GT30 turbine and their unique turbine housing . I think it's obvious that they'd have tried the full sized turbine first before getting Garrett to shorten the blades a few mm - bit higher gas speed to liven the compressor speed up .

Honestly Garrett must have tested the GTX3067R and I think if it had been a flop they would put their reputation ahead of customer R and D .

Woolverine has good things to say about his 2835 Pro S and if you PM him he could tell you how he got his . I hear they are not available new anymore but there may be some old stock out there if you want to spend the coin on a new kit . Just remember that the only non Garrett parts on those turbos is the housings and dump pipe , the cartridges should still be available new .

Heaps of threads to read here at SAu on 3071Rs and 2835 Pro S turbos .

A .

Edited December 8, 2013 by discopotato03

[discopotato03]

I did a bit more searching on this GTX3067R but still nothing conclusive . The thing is that it's a 47 lb/min compressor side which in bleeding edge theory might get 470 worth of airflow but this is the real world . On the site I was just at someone claims that 9 hp/lb of air on E85 is doable so maybe 420 crank ? I can just as easily suggest 8 hp/lb on 98 ULP so 380 crank ? All theory - based on hot air ... Even if the 420 or 380 was the case it isn't going to to be either at the wheels .

It's hard for me to see this turbo as being much more than a GTRS with a bit better hot side .

This whole 300 kw/400 Hp at the bags seems to be hard to do neatly with Garrett turbos because it's right in the crossover of compressor housing sizes B to E so you just miss out or overshoot . To get 49-50 + lb/min flow means the E housing and either 71 or 76mm compressors .

My gut feeling is that this turbo , or the similar GTX2867R , is better suited to two litre fours and that 2.5L sixes need bigger housings and enough free flow to let the engine work properly off boost . It should be making ~ 25% more torque anyway so sizing the dryer to boost a little later wouldn't be a bad thing .

A .

[M@&k]

...

It's hard for me to see this turbo as being much more than a GTRS with a bit better hot side .

...

Agreed. But then I would describe the HKS Pro S in the same way. Although it had the 56T instead of 52T compressor right so I guess a step up on cold side too.

Gah, I dunno.

[Lithium]

I did a bit more searching on this GTX3067R but still nothing conclusive . The thing is that it's a 47 lb/min compressor side which in bleeding edge theory might get 470 worth of airflow but this is the real world . On the site I was just at someone claims that 9 hp/lb of air on E85 is doable so maybe 420 crank ? I can just as easily suggest 8 hp/lb on 98 ULP so 380 crank ? All theory - based on hot air ... Even if the 420 or 380 was the case it isn't going to to be either at the wheels .

It's hard for me to see this turbo as being much more than a GTRS with a bit better hot side .

This whole 300 kw/400 Hp at the bags seems to be hard to do neatly with Garrett turbos because it's right in the crossover of compressor housing sizes B to E so you just miss out or overshoot . To get 49-50 + lb/min flow means the E housing and either 71 or 76mm compressors .

My gut feeling is that this turbo , or the similar GTX2867R , is better suited to two litre fours and that 2.5L sixes need bigger housings and enough free flow to let the engine work properly off boost . It should be making ~ 25% more torque anyway so sizing the dryer to boost a little later wouldn't be a bad thing .

If you are talking crank hp - with a good setup and tuning you should be capable of getting just over 10hp per lb/min on BP98 and around 12hp per lb/min on E85... at least that is what I use when making thumb sucks of what to target. I think the GT28 hotside is a little weak for anything capable of flowing much over 40lb/min on under 20psi, so the difference in suitability between an HKS GT-RS and a GTX3067R on an RB25 may be bigger than you'd expect... I'd be far less quick to object to a GTX3067R on an RB25 than I would be an HKS GT-RS/GT2871R, not that it's saying much because as you now I am not a big fan of that combination

Just hypothetically speaking of course. Would need to see some actual results, but I'd say it should be able to get in range on 270kw - depending on dyno, I'd have no issue with saying it'd be capable of hitting it on a hubber but it may struggle to go over 260kw on the harsher reading rolling road dynos on BP98. I'm guessing that such a turbo would feel wicked under foot on an RB25!

[wolverine]

I'm sure it would be fine but you are in the territory of a good hiflow. Why bother? Get hypergear to bolt it together with all the super slippery lubed to the max unobtanium bearing centre and save a lot of head fark.

I have done too much head fark over the years.

[M@&k]

Yeah I think this is what has been gnawing at me lately. If the 3067 is not going to do much more than 260kW at the wheels, then might as well get a Hypergear bolt on and not have to worry about a new dump/front pipe.

Always had it in my mind that the 3067 would be able to do 270rwkW with potential for a bit more (280) after cams. What I really want is for this to be a Pro S replacement with a bit newer tech and for half the dollars. But just because I want it to be that way does not make it so unfortunately...

[M@&k]

Have been looking at comp maps for GT2871-52T, 3071 56T, and GTX3067. Pic below shows comparison.

Speed lines are all 120,000 rpm.

Efficiency lines are all 76%

At a pressure ratio of 2.2 (roughly 18 psi), the GTX3067 looks like it will only do a smidge more than the GT2871. So perhaps shouldn't expect much over the GT-RS top end. It does seem to be quite a lot more efficient at mid flow, so more mid range. More mid range than GT-RS is not what I would be looking for though.

Not sure what to make of the difference in speed lines.

[discopotato03]

Nah keep the balls rolling .

Actually I think there is a bit more to the 2835 Pro S than a GTRS . HKS went from GT28 and T04B sized housings to GT30 and I think T04E ones . The physical dimensions of the wheels didn't change lots though the turbine trim went from 76 to 84 . And compressor trim from 52 to 56 .

Yes the GTRS has its limitations and part of the compromise is being an almost direct replacement for the std Hitachi ceramic turbo . Really aside from water and oil lines a GTRS falls in between the std suction hose and dump pipe , and straight on the manifold . Quick easy reliable and tunable - within limits .

Don't forget what you replace when you flick the standard fragile hissy fit turbo and remember what Japanese workshops charge .

The 2835 Pro is more of the same but you get the exhaust and inlet bits to make it a bolt on system .

Also these kits were out long before Garrett made IW T3 flanged GT30 turbine housings so in those days you had to use some bastardised alternative T housing and or went external wastegate .

There are still gaps in the range but they are closing and there are more alternatives too like from FP and BW . And Hypergear as well .

A .