http://cgi.ebay.co.uk/GSRACING-GSR-...arts_Vehicles_CarParts_SM?hash=item33551b3e11
Also in this months jap mag
Also in this months jap mag
fro people who want big power and stay british
- Thread starter nimhbk
- Start date
Im sure Makaveli Seven off here will be on at some point to tell you a bit more about these as he works for holset. There's been a fair bit off discussion on these turbos on here and the modifiers but as of yet i believe they are still untried on a gtir. Would love to see what results they produce though.
Makaveli_se7en
Member
Far better than any Garrett, in fact you should all buy at least 10 and keep me in work :lol:
In all seriousness though the problem i see with that turbo is the problem I see with all Holset turbos on petrol applications, in that they still use a Holset cast iron turbine housing. Which is fine for diesel, not so great for petrol engines due to the higher exhaust gas temperatures. In all fairness though our turbo's are designed to be used on diesel trucks with warrenty periods cover up to a million miles, so whether it would ever become an issue on vehicle that may only ever do 100,000 miles in its life time is debatable.
There is also some very amusing marketing bullshit in that advert:
1. Reseacrh into smaller turbine housing - one phone call to our after market division (in fact I'm pretty sure we also make a couple of smaller housing for that turbine wheel if it was required)
2. Super compressor wheel - all of our compressors are super thank you very much :roll:
3. Twin scroll on a 4 cylinder I debated in great detail on the modifiers forum, but I don't think it will offer much benefit over a single entry turbine (although if it was going on a 6 cylinder it would be a different story)
4. "legendary bearing system" - I suppose journal bearings are pretty well known.
5. Sounds amazing - The amount of time we spend on noise research and baffles to hide that noise for oem's :doh:
Having sounded quite negative, I do think it is an interesting option and fills the 525-600bhp hole which Garrett have in there catalogue. There are several 200sx that are running them with good results, one guy on Nicoclub.com went as far as saying none of my cars will ever see a garrett turbo again: http://nico.zeroforum.com/zerothread?id=384139
In all seriousness though the problem i see with that turbo is the problem I see with all Holset turbos on petrol applications, in that they still use a Holset cast iron turbine housing. Which is fine for diesel, not so great for petrol engines due to the higher exhaust gas temperatures. In all fairness though our turbo's are designed to be used on diesel trucks with warrenty periods cover up to a million miles, so whether it would ever become an issue on vehicle that may only ever do 100,000 miles in its life time is debatable.
There is also some very amusing marketing bullshit in that advert:
1. Reseacrh into smaller turbine housing - one phone call to our after market division (in fact I'm pretty sure we also make a couple of smaller housing for that turbine wheel if it was required)
2. Super compressor wheel - all of our compressors are super thank you very much :roll:
3. Twin scroll on a 4 cylinder I debated in great detail on the modifiers forum, but I don't think it will offer much benefit over a single entry turbine (although if it was going on a 6 cylinder it would be a different story)
4. "legendary bearing system" - I suppose journal bearings are pretty well known.
5. Sounds amazing - The amount of time we spend on noise research and baffles to hide that noise for oem's :doh:
Having sounded quite negative, I do think it is an interesting option and fills the 525-600bhp hole which Garrett have in there catalogue. There are several 200sx that are running them with good results, one guy on Nicoclub.com went as far as saying none of my cars will ever see a garrett turbo again: http://nico.zeroforum.com/zerothread?id=384139
I didn't know a lot about VNT's except experience in diesels and the latest 911 turbo but thought I always needed one for my R in the future once the technology becomes mainstream on petrol engines. Reading the Nico club post made me think "is that it?, full boost at 4.2K and 397hp?"
I did a search and found this article:
http://www.gtr.co.uk/forum/90348-hks-vnt-turbo-prototype.html
I'm now less convinced this is the great white hope and a little sad about that.
I'd be interested to hear makavelli7's feedback but maybe this is why he said its a good turbo for the gap in the 525-600hp garrett range?
If possible, a little closure on all this would be appreciated.
Jim
I did a search and found this article:
http://www.gtr.co.uk/forum/90348-hks-vnt-turbo-prototype.html
I'm now less convinced this is the great white hope and a little sad about that.
I'd be interested to hear makavelli7's feedback but maybe this is why he said its a good turbo for the gap in the 525-600hp garrett range?
If possible, a little closure on all this would be appreciated.
Jim
Link please George. I'm struggling to find it on the mods forum
Think it was me! , read quite alot about them good and bad .
Most bad things talk about the cast housings and the temps of a petrol engine , there seams to be a few people using them now ,so for half the cost of a garrett i was going to give it a go:-D
Makaveli_se7en
Member
The reason I said there seems to be a gap in the Garrett range is on the GT30 frame size you've maxed at 3076 (there is an 3082 I think but that’s quite a mismatch in turbine to compressor) which is good for 550bhp max, but most seem to hit around 530bhp with it. You then move into the GT35's (smallest of which is a GT3582) which to me seem to be 600bhp+ turbos. So there’s nothing really in the high 500's. Please correct me if you think I'm wrong.
Not sure why you’ve mentioned VGT’s all the HX turbos are fixed geometry, the HE series are VG. But I did skim read the first page of the link. As for variable geometry turbo chargers are far from a waste of time, none of the current generation of heavy duty diesel engines would be able to meet the latest emissions regs without them, which is probably why all the big turbo manufacturers have a variant of them.
I think that maybe this is where the issue lies, they have been predominately developed to control emissions on diesel engines (by providing back pressure to drive high percentage egr loops) rather than to give better transient performance on petrol applications. Porsche so far have been the only people to do this using a Garrett swing vane turbo. I think unless emissions regulations for petrol engines get tighter there is not a lot of incentive for oem’s to develop VGT systems given the additional cost of the turbo, electronic actuators and the increased complexity of the development of suitable engine control systems and this why it’s only been seen so far on a high end car like the 911 turbo. There is also the issue of higher egt temps on petrol applications which require exotic materials in the bushes for the swing vane mechanism (as used by Garrett, we use an axial sliding ‘nozzle ring’ which might be better suited to petrol, but has its own issues). Given this I personally see it will being a very long time before tuners are offering VGT turbo upgrades for fixed geometry turbos.
Having said that I found a guy in the states that had ghetto rigged a HE351 so that the VG mechanism was operating from the wastegate actuator on a 2l petrol engine (think it was an mx6 of all things) running megasquirt said he had got good results, so you never know.
Sorry for the long ramble, shouldn’t get me started on turbos (my job) or brake discs (my Ph.D):lol:
Not sure why you’ve mentioned VGT’s all the HX turbos are fixed geometry, the HE series are VG. But I did skim read the first page of the link. As for variable geometry turbo chargers are far from a waste of time, none of the current generation of heavy duty diesel engines would be able to meet the latest emissions regs without them, which is probably why all the big turbo manufacturers have a variant of them.
I think that maybe this is where the issue lies, they have been predominately developed to control emissions on diesel engines (by providing back pressure to drive high percentage egr loops) rather than to give better transient performance on petrol applications. Porsche so far have been the only people to do this using a Garrett swing vane turbo. I think unless emissions regulations for petrol engines get tighter there is not a lot of incentive for oem’s to develop VGT systems given the additional cost of the turbo, electronic actuators and the increased complexity of the development of suitable engine control systems and this why it’s only been seen so far on a high end car like the 911 turbo. There is also the issue of higher egt temps on petrol applications which require exotic materials in the bushes for the swing vane mechanism (as used by Garrett, we use an axial sliding ‘nozzle ring’ which might be better suited to petrol, but has its own issues). Given this I personally see it will being a very long time before tuners are offering VGT turbo upgrades for fixed geometry turbos.
Having said that I found a guy in the states that had ghetto rigged a HE351 so that the VG mechanism was operating from the wastegate actuator on a 2l petrol engine (think it was an mx6 of all things) running megasquirt said he had got good results, so you never know.
Sorry for the long ramble, shouldn’t get me started on turbos (my job) or brake discs (my Ph.D):lol:
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No apology needed, I knew it was your job which is why I raised it ;-)
Thanks for the feedback
I had expected you were suggesting the HP range as after a 3076 the Garrett range is a little limited until a GT35. I hadn't realised the HX's were fixed geometry so sorry for getting the wrong end of the stick but thanks for the polite explanation anyway 8)
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Makaveli_se7en
Member
A bit off topic but if you want a really cool turbo that shows off some of the future of turbocharging, check out turbo on the new Ford scorpion diesel engine:
http://www.autoblog.com/2009/08/31/beware-the-scorpion-2011-ford-super-duty-gets-all-new-6-7-liter/
Back to back compressor wheels with dual entrance
Dual entrance turbine housing
Wastegated VG mechanism
Shame its not one of ours :doh:
http://www.autoblog.com/2009/08/31/beware-the-scorpion-2011-ford-super-duty-gets-all-new-6-7-liter/
Back to back compressor wheels with dual entrance
Dual entrance turbine housing
Wastegated VG mechanism
Shame its not one of ours :doh:
Very clever piece of kit, I like the dual entrance setup. Obviously been designed from the bottom up with the layout of the engine
Empty Pockets
New Member
That turbo in the link isn't a proper holset, its made with a a mix of different parts based on a holset. It will not spool up any quicker than a ballbearing turbo (as it uses a journal bearing), the quick spool up sales pitch is due to using the twinscroll/split pulse exhaust housing WITH a twinscroll/split pulse manifold, without the manifold it will spool slower than the equivalent bb turbo fact. I have spoken lots to a guy who had one on his forged sr20det 200sx, that exact turbo in the link had it spooling at 5500rpm on a non-twinscroll topmount manifold. As far as twinscroll/split pulse set-ups on a four pot go, the evo boys have had good results, as was said on the other site, its the 'cost v gain' that scare's people off, not the fact that it doesn't work on a four pot lol.
Makaveli_se7en
Member
I have never said that twin scroll does not work on a 4 pot. I said that there is little benefit as the exhaust pulses are well separated anyway and that its not as simple as saying twin scroll are better than single entry. I'm surprised that it would make around 1500rpm difference, which is what it would suggest if the guy with the 200sx is spooling at 5500rpm and ebay are suggesting it spools like a GT30. I think it says more about the propaganda in the ebay auction, it may also be that using a divided housing on a single entry manifold is a horrible combination.
The guy on the Nico forum said his was spooling at 4200rpm with twin scroll and I have seen another (on driftworks) that claimed full boost at 4600rpm (starting at 3500rpm) with single entry again on a 200sx. Suggesting a twin scroll may gain you 500 rpm, which is not to be sniffed at. However it’s hard to draw comparisons due to potential differences in engine spec and as HX35 is simply a frame size, bit like saying GT30 and has many variants. To quote one of my previous posts:
It’s true that if you had identical turbos and the only difference was the bearing system the bb turbo would spool sooner, but only by a few hundred rpm. Where you see more of a difference is in the time taken to reach full boost, once the turbo has started spooling the bb turbo will reach full boost sooner than the journal bearing one. Ball bearings also create less bearing losses giving the potential for more power. However the rotor system has less of an influence than the aerodynamic components on the end of it (that’s what I tell the rotor systems boys anyway lol). An efficient well matched compressor and turbine with journal bearings would still out perform a poor turbine/compressor on ball bearings.
Again it comes down to cost vs benefit. Is it worth paying nearly double for a turbo to gain a few hundred rpm in spool? Also a journal bearing system can be rebuilt cheaply; ball bearings need new cores and tend to self destruct if a boost hose blows off. One possible way round it is polished billet journal bearing which are meant to offer bb levels of performance, but I cannot find any information on these.
I personally don’t mind paying through the nose for ball bearings and have a Garrett GT3071r and have just bought a GT3076r to replace it. At some point in the future I may try a Holset turbo if I can get the guys in special products to come up with something trick for me.
The guy on the Nico forum said his was spooling at 4200rpm with twin scroll and I have seen another (on driftworks) that claimed full boost at 4600rpm (starting at 3500rpm) with single entry again on a 200sx. Suggesting a twin scroll may gain you 500 rpm, which is not to be sniffed at. However it’s hard to draw comparisons due to potential differences in engine spec and as HX35 is simply a frame size, bit like saying GT30 and has many variants. To quote one of my previous posts:
Looking at the pictures of that turbo the only item I see that’s not a Holset one is the compressor cover, unless they've changed something in the core. I question the logic in changing the comp cover as they are matched to the impeller. Unless they are offering a warranty I see no reason not to go to our aftermarket division and see what price they’d do.
It’s true that if you had identical turbos and the only difference was the bearing system the bb turbo would spool sooner, but only by a few hundred rpm. Where you see more of a difference is in the time taken to reach full boost, once the turbo has started spooling the bb turbo will reach full boost sooner than the journal bearing one. Ball bearings also create less bearing losses giving the potential for more power. However the rotor system has less of an influence than the aerodynamic components on the end of it (that’s what I tell the rotor systems boys anyway lol). An efficient well matched compressor and turbine with journal bearings would still out perform a poor turbine/compressor on ball bearings.
Again it comes down to cost vs benefit. Is it worth paying nearly double for a turbo to gain a few hundred rpm in spool? Also a journal bearing system can be rebuilt cheaply; ball bearings need new cores and tend to self destruct if a boost hose blows off. One possible way round it is polished billet journal bearing which are meant to offer bb levels of performance, but I cannot find any information on these.
I personally don’t mind paying through the nose for ball bearings and have a Garrett GT3071r and have just bought a GT3076r to replace it. At some point in the future I may try a Holset turbo if I can get the guys in special products to come up with something trick for me.
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Makaveli_se7en
Member
Thinking about it a bit more (I will shut up after this I promise) I'm not sure I'd want to buy a turbo with some odd ball comp cover. There are no guarentees that they've done any form of containment testing what so ever. I for one don't fancy bits of impeller flying through the bulk head at me should the worst happen.
Empty Pockets
New Member
The point i'm making is this isn't a holset turbo, they built this turbo (from various other parts) as obviously you guy's don't make one to the same spec (otherwise they wouldn't of made it), therefore you can't phone up your r&d for flowcharts on a turbo you don't make, We will have to 'agree to disagree' on the benefit of split pulse on a four pot as it costs no more than any other high end/high power set-up, As said last time, having a twinscroll manifold without turbo will give you none of the quick spool benefits, and same the other way round. I will say in my opinion every 100rpm makes a difference, especially at the 550-600hp mark, money wasn't a consideration when i chose my turbo and i did look long and hard at using a "holset" for my set-up, i remember telling you about the egt problems with the housing and you being sceptical, something about loads of motorsport use in 600-something-hp dakar buggies with no problems? This 'based on a holset' turbo in the listing is comparable to a gt35, a gt35r will out perform it in spool up every time, The only thing going for this turbo is its price.