G30-770 vs PT6062 on Street RB26. Or Other ?

[Butters]

So I have a Nissan Cefiro with an RB26.   It is my daily drive and I take the kids in it often.

I'd like a turbo setup that gives me 500-600rwhp on e85 but has great response and power in the lower rpm range.

At the moment these two turbos look like the best options, i welcome others.

 

My current thoughts are I have used Garrett for 15+ years and they have been nothing but excellent. I have seen a lot of people having issues with precision's but its hard to call as they are often on full race cars that replace pistons as often as they do turbos.  The lack of water cooling on the precision worries me too as I will be doing runs to the shops, not sitting idling but shutting off.

The precision's seem to consistently out perform the garrets though in both spool and outright power.  Garrets GTX range seems barely an upgrade from the GT range. I have seen good results on the G25 -550 but very average ones on the G25-660 and nothing really so far on the G30.

 

 

[GTSBoy]

I think the cult of Precision is winding down now. The choices seem to be more in the Garret G series and the BW EFR. EFRs are very well proven in the power range you're talking about.

[Lithium]

Do you have any preferences in terms of flange? As per Gtsboy, surprised you didn't mention the EFR range and did Precision - Precision are not really big players at this kind of power range and Borg Warner are arguably king, the G series looking like at best they are only just catching up to the EFR range.

I haven't found a single result for G30s, yet- not for lack of keeping an eye out. I would love to see a G30 770 on a set up like this so just do it

I suspect that it has a chance to be a banger of s thing for that power target, not just saying that because I want to see someone do it.

If you are feeling adventurous the Xona Rotor XR7164S with the trick UHF turbine looks mega interesting but could be raising the hand for being a guinea pig.  There are at least local dealers for Xona now and the results for the UHF range that I've seen so far have been pretty nuts so an intriguing option. 

 

[Butters]

Guess I would be looking at an EFR 8374 to make this sort of power ?

[Butters]

Not got the manifold as yet so flange choice is open. T4 split would be nice as it gives the most options but I do release the G30 is v-band only at the moment.  

[Lithium]

17 hours ago, Butters said:

Not got the manifold as yet so flange choice is open. T4 split would be nice as it gives the most options but I do release the G30 is v-band only at the moment.  

Yeah, knowing Garrett they won't do the G30 in T4 split pulse - they haven't seemed too popular.  Would be nice if there were more standard V-band options, tbh I haven't looked too far into it but I'm not sure how far the v-band option for the G30 range will stretch.   Be nice if you could go all the way to a G35-1050 or something else with the same flange.

[GTSBoy]

I'm at the point of wondering why all turbo manufacturers don't just say, "Right now, as of this moment, no more flanged housings. We're only doing V-bands and all of you boost monkeys are just gunna have to come with us."

After 3-6 months of predictable internet moaning, the new world order would be in place and none of the GenZs would even remember that you used to be able to get them with a flange.

[Lithium]

1 minute ago, GTSBoy said:

I'm at the point of wondering why all turbo manufacturers don't just say, "Right now, as of this moment, no more flanged housings. We're only doing V-bands and all of you boost monkeys are just gunna have to come with us."

After 3-6 months of predictable internet moaning, the new world order would be in place and none of the GenZs would even remember that you used to be able to get them with a flange.

I'm ok with this when collecting <4 cylinders, but otherwise twin scroll + v-band don't work for me, and throwing away pulse conversion also doesn't work for me, so your idea has flaws

[GTSBoy]

I dunno. I've bought 5" & 6" v-band sets out of China over the last couple of years (for other applications) for only a handful of dollars. There doesn't seem to be any reason why a v-band can't be large enough to flow all the gas you want and there isn't really much of a reason why dividers couldn't be arranged to provide sufficient separation through the joint area. Tolerancing would become more critical perhaps. I imagine a divider that comes up out of the turbo's inlet flange that meets a split divider coming out of the manifold. By "split divider" I mean a divider that is not as narrow - is wide enough for a slit in the edge facing the turbo's divider. The turbo's tongue then slips into the other one's slit** and doesn't go all the way in to the bottom of the slit. So there is some room for thermal expansion, something of a labyrinth seal to reduce cross talk in the pulses. (I've had similar ideas for twin into single wastegates, except that they're not as critical because when it matters most you can get the wastegate's poppet valve to close up on the divider.)

 

**It's not as dirty as it sounds.

[Lithium]

lol.

 

My concern is more that I've heard bugger all people using the divided v-band housings, but when I have heard of it - it seems people are having issues making manifolds sturdy enough to have a nice collector to suit the flange and not end up cracking or anything else less than ideal.  

[GTSBoy]

I think there will soon be a revolution in manifold design and manufacture techniques. We're seeing it in industry now with the various rapid prototyping options that are around. But even with what I do, it is becoming so easy to draw something with a fairly complicated shape and get it cast in high grade stainless in China and shipped to Australia in a week or so. So I have no doubt that manifold collectors and the like will start getting drawn by the more skilled workshop operators here in Oz and done using similar methods. It's all getting increasingly possible. It just seems difficult if you remain in the hand fabbed tube manifold world and don't look elsewhere. I'm not saying that whole manifolds will get done that way, but the tricky parts to make by hand (so that they work and don't break) could certainly be done using new techniques. All it needs is someone to take the plunge and start. They will build up a design library and work out when it is better to cast, or when you should just 3d metal print, etc etc.

[Lithium]

This is true.  Drifting off topic but more people are already showing up and designing cast manifolds, I have been pondering whether to invest some time with a design I've been playing with elsewhere which would probably earn scowls but have a lot of advantages with little disadvantage.   No point having the tech we have now without using it.

[GTSBoy]

If it is castable, I can point you to a prototyping outfit in China that do good work for not many buckkeroons. What you do is send them a 3D drawing of something that is quite similar to what you want (but not actually exactly what you want) for scoping & quoting. If you don't decide to go forward, your IP is not sitting in someone's office in China. If you do decide to go forward, you send them the actual design and your commercial relationship with them gives you warm fuzzies (while they probably steal your shit anyway!)

[SimonR32]

6062 is bigger than mine in terms of outright power so it's way more than you want.

Ryan's 240Z goes 600hp with a 5558 on a RB25, so that's easy enough for your goals

[r32-25t]

1 hour ago, SimonR32 said:

6062 is bigger than mine in terms of outright power so it's way more than you want.

Ryan's 240Z goes 600hp with a 5558 on a RB25, so that's easy enough for your goals

They claim the 6062 makes more but I’m yet to see a result that backs it up 

[Lithium]

10 hours ago, r32-25t said:

They claim the 6062 makes more but I’m yet to see a result that backs it up 

There have been some pretty big numbers from them to be fair, definitely more than a G30-770 will support but while I haven't seen results from a G30-770, it seems pretty reasonable to expect it to spool better too.  The G30-770 is a more sensible match to this power range I think

[Butters]

There have been some pretty big numbers from them to be fair

 

Any examples on hand ?  

Google gives me US dyno results from 480-750rwhp and none on a nissan.  Always so hard with American dyno's to actually know what power that really is, not yet seen a 1/4 mph to get an idea.

 

 

[Lithium]

On 01/11/2019 at 2:59 PM, Butters said:

Any examples on hand ?  

Google gives me US dyno results from 480-750rwhp and none on a nissan.  Always so hard with American dyno's to actually know what power that really is, not yet seen a 1/4 mph to get an idea.

Not on hand, sorry - but I have seen results (1/4 mile and dyno) which have been enough to make me treat the 6062 as though it should be treated a larger turbo, both in spool and power capacity than you'd expect from the wheel sizes.   650-750whp on a US dyno is about the area I was thinking, which is pretty decent from a 60mm turbo - normally more what you expect from a good 62mm.

Edited November 3, 2019 by Lithium

[hattori hanzo]

On 04/11/2019 at 6:45 AM, Lithium said:

Not on hand, sorry - but I have seen results (1/4 mile and dyno) which have been enough to make me treat the 6062 as though it should be treated a larger turbo, both in spool and power capacity than you'd expect from the wheel sizes.   650-750whp on a US dyno is about the area I was thinking, which is pretty decent from a 60mm turbo - normally more what you expect from a good 62mm.

anyone got any results out of aus for the 6062? 

[WMDC35]

There's 1 in the 25 dyno results a couple of pages back