I notice in the early days of the discussions on these turbos, the common wisdom seemed to be only go for the RS if you're looking for relatively big power as the RS is laggier than the R. However, I've seen a few posts lately saying there's b*gger all difference in lag and to got for the RS if budget allows. I also see on alot of the vendors website the RS advertised as a fast spooling turbo. In addition, I see alot of people that wanted an R in the early days, now have an RS in their sig? Can people with direct experience of this comment?

Have a look at the graphs in the PTS unichip thread. The 0.64 RS spools about the same as the 0.64 R - maybe 200 rpm difference. The bigger housing RS is more laggy.

You can get 340+ bhp with the R as proved by myself and Sheiks - but both our cars have headwork and are balanced. Cars make 350 + on the RS with standard block and head with the right ancilliaries.

If you are that way inclined then you can run more boost on the RS - up to 1.8 bar midrange - where as the R is on the limit at 1.4 / 1.5. If you want to spend a lot of cash and get serious power then the RS is the way to go. If you are happy with a shade over 300 then go for the R. If you want 300 with very quick spool and midrange then go for a hybrid.

<img src="/forum/images/graemlins/smile.gif" alt="" />

There is also the R/RS hybrid which is what Markus got 378BHP and 340lbs/ft torque on (also with headwork)

John

In terms of performance, a hybrid is for me! I'd very rarely get the opportunity to exploit any more than 300BHP. When I first started thinking about a new Turbo, that was my choice (I thought I could get one relatively cheap). However, I've big concerns over longevity, I don't want to shell out for a Hybrid that will last 1/3 of the time of a GT28R(S), especially when they're the same price. The thought of handing over £750 for a reconditioned turbo just doesn't seem right! I'd prefer to go for a GT28R(S) with straight induction that will spool up similarly to my standard turbo (with the added benefit of a massisive top end) rather than a hybrid that could go bang within a few months/years. <img src="/forum/images/graemlins/frown.gif" alt="" />

the GT turbos are much stronger than the hybrids due to design. Th RS turbos are slightly better designed as well ive been told but god knows what the difference is over than the vanes used for them. it depends what the car would be used for. Knowing the roads south of the borded, but not by much, i would say a GT28r would be best for a daily driver with teh right mods, like straight induction and H&S downpipe, it should spool up well.

This was the conclusion I had come to, I might go for the RS if I can get a good deal. Re driving down here - it's a completely different expereince to the UK. I used to live in Bristol/Bath ... lots of great roads - had loads of fun on the way to work... now it's pure frustration - it's nearly pointless having anything over 30 BHP, let alone 300BHP <img src="/forum/images/graemlins/crazy.gif" alt="" />

Sounds interesting David. Are westward fitting for you?

Well its kinda pointless unless you have soemthing to take all the potholes in and can overtake very quick in my experience the roads are twisty pothole ridden things all over the show which lets the country down loads i feel but keeps it looking good i guess and tourists out as well <img src="/forum/images/graemlins/laugh.gif" alt="" />

@Ally - not sure who'll do the fitting, haven't bought it yet, will probably be westward or ECC!

@Kingpleg - I said nearly! It's still possible to have loads of fun (just about)... <img src="/forum/images/graemlins/laugh.gif" alt="" />

Was looking at some of the PTS results, Markus's figure is fairly massive! Sean_C got some nice results with this turbo also - my setup will probably end up being more similar to his. What's the spec of the R/RS hybrid? Is this the one with the RS compressor cover and the R turbine? What's the advantage of this over a plain R or RS?

I also have this turbo you get the best of both worlds. Faster spool up and higher boost/flow. Don't get the on/off feel with the RS it's nice and progressive. Here is the map for it:

http://jayman.bulldoghome.com/photos/bdres/jayman_bulldoghome_com/gt2860R_707160-5_comp_e.gif

Wrong map there, that's for the GT28RS <img src="/forum/images/graemlins/wink.gif" alt="" /> This is the GT28R compressor map

Doh, you are talking about the the 28RS hybrid so your compressor map is correct <img src="/forum/images/graemlins/grin.gif" alt="" /> I still think you will find it fairly on/off though as the turbo comes on boost relatively late and hard but it will spool ever so slightly quicker than the standard 0.64 turbine.

I think you will find my map is correct as this is the map for the RS:

http://jayman.bulldoghome.com/photos/bdres/jayman_bulldoghome_com/gt2860RS_739548_comp_e.jpg

This is the map for the R:
http://www.atpturbo.com/root/maps/images/gt28rcompress.gif

And this is the map for the Hybrid:
http://jayman.bulldoghome.com/photos/bdres/jayman_bulldoghome_com/gt2860R_707160-5_comp_e.gif

Your graphs aren't making sense there because you show three compressor maps two of which are for the 28RS yet they are different?! The hybrid 28RS uses the same compressor as a normal 28RS it is simply the turbine wheel which is taken from the 28R.

Garrett must have updated their compressor maps because ever since I have known the GT28RS i.e. the last 2 years (and I think everyone on here!), the compressor map has always been the one I showed and is still used by ATP Turbos. Did the 28RS not get the name "Disco Potato" after the odd potato looking compressor map that I linked to? The GT28R compressor map is the same as my link.

TurboJ,

The map you show for the hybrid is the one that's been used for a long time for the GT28rs on all the websites I've seen including ATP themselves?

Why do you think it will give you the 'best of both worlds'? will it spool as quick as a 28r and as much top end power as a gt28rs <img src="/forum/images/graemlins/confused.gif" alt="" />

Joe

'best of both worlds' means that it is less on/off (a symptom of the turbine wheel on the RS), provides useful power at lower rpm and has a better top end than a 28R.

I haven't driven a car with one on so can't attest to these features, but Markus consistently good 1/4m times at Forza Italia tells more than one story. I don't think anyone has put in as many sub-13s times one after another in one day.

John

Yes, I presume it was meant as an 'in-between' unit between the gt28r and the gt28rs in terms of spool up and power. <img src="/forum/images/graemlins/smile.gif" alt="" />

Yes, very good times he has done there,.. very good <img src="/forum/images/graemlins/smile.gif" alt="" />

Joe

Looking at the PTS results the R/RS hybrid seems to give as much power low down as a GTI-R hybrid, but not quite the slam of a Superspool on similar setups - very tempting!

David,.. who else has the r/rs hybrid then? I was looking at SeanC's pts results with the r/rs hybrid and Markus's results on the graphs (they're on spearate graphs)....,but the spool-up appeared not as good as my 0.64 gt28rs??

I know you can't really compare with RR printouts in terms of spool-up, so not making any judgement with this,.. but be interested to know which ones you were referring to? are you sure you're not looking at SeanC's T28 hybrid results because his GT 28 r/rs results are not on the comparison graph as far as I can see?

PTS Torque comparison

SeanC's results GT28 R/RS hybrid

Joe

i was just manually comparing Sean_C's R/RS result with his own Superspool results and to Hamster's GTI-R results! No graphs I'm afraid, just looking at the results and writing them down on a notepad <img src="/forum/images/graemlins/frown.gif" alt="" /> I think deep down I want a superspool or at least something that isn't all top end power ... just want something that will last as well!

I had a GTi-R hybrid for 3 years, until finally the oil seals went on it, but it did have a hard life tbh.

I've driven coupes with standard turbos, T28 hybrids (GTi-R), GT28r, and GT28rs (0.64 and 0.86), and I think really you need to be looking at either a superpool or a gt28r maybe the r/rs hybrid,..maybe.

the GT turbos are a lot more efficient design, and if it was me (its not <img src="/forum/images/graemlins/wink.gif" alt="" /> ) I would consider a GT turbo, the bearing design is far superior, and ok, thay are not quite as quick spooling as a T28 hybrid, but they make up for it everywhhere else and really after 10 minutes behind the wheel you really won't notice that much of a difference in spool-up.
The prices have now really come into the gt turbos favour, and ok they can break,... but really how many have broken?,... hardly any, only a couple of the high boost guys, whereas the journal bearing turbos oil seals are going all the time.

However, if you want the ultimate low down spool up, responsive turbo that will be plug and play then a superspool will be your thing <img src="/forum/images/graemlins/smile.gif" alt="" />

regards

Joe

First of all this is what I think about the maps. Garrett first release the GT28R with a 55trim comp and 62trim exhaust as we know this is the map as they rate it upto 310bhp:
http://www.turbobygarrett.com/turbobygarrett/catelog/Turbochargers/GT28/GT2860R_707160_7.htm

Then they produced the GT28R with a 60trim comp and 62trim exhaust but I have never seen a proper Garrett map for this. This is the GT28R we all know rated to 340bhp and buy from ATP but according to Garrett’s website it don’t exist?

http://www.atpturbo.com/root/maps/images/gt28rcompress.gif

Then there is the GT28RS that’s what ATP call it but NOT Garrett with a 62trim comp and 72 trim exhaust which is the disco potato we all know rated to 360bhp
http://www.atpturbo.com/root/maps/images/gt28rscompress.gif
or
http://www.turbobygarrett.com/turbobygarrett/catelog/Turbochargers/GT28/GT2860R_707160_5.htm

Then there is the GT28RS officially made by Garrett which they call the discs potato which also has a 62trim comp and 72trim exhaust but the maps are completely different.
http://www.turbobygarrett.com/turbobygarrett/catelog/Turbochargers/GT28/GT2860RS_739548_1.htm

I think the problem is ATP list different turbos to what Garrett list so that is where the confusion lies.

I wish somebody can just put it all straight as I’m now getting confused <img src="/forum/images/graemlins/confused.gif" alt="" />

Thanks Joe, initially my gut instinct was to go for the Superspool. Then, after thinking about the practicalities (cost/reliability) I had kind of come to the conclusion that the GT28R was the right choice. Then I heard that the RS isn't all that laggy after all... but maybe it is? The R/RS hybrid is another option, but I think I need to do more research. I'm not in a hurry, my current standard turbo is OK, so thankfully I can take my time <img src="/forum/images/graemlins/smile.gif" alt="" /> I'll keep on trawling through the graphs on the forum - there's alot of info to take in <img src="/forum/images/graemlins/crazy.gif" alt="" />

Dual ballbearing technology on the CHRA does not make them bulletproof. I have had a ball bearing race failure which potentially is far more dangerous than a plain thrust bearing assembly failing because you end up with a pile of tiny steel balls spat out that can end up in your sump or in your intake

They are more reliable as a whole but mine lasted less miles than my standard turbo lasted and I don't run high boost most of the time (1.25 bar is my standard boost). I don't think anyone on here has done high mileage with a ballbearing turbo either aside from myself.

Ok I have been doing some research into this ATP’s GT28R is not a GT28R It’s really a GT25R they just name it different.
So there GT28R
http://www.atpturbo.com/Merchant2/mercha...tegory_Code=GRT
we are really buying this:
http://www.turbobygarrett.com/turbobygarrett/catelog/Turbochargers/GT25/GT2560R_466541_4.htm

Which is rated to 330BHP

The GT28RS ATP sell is really the GT2860R
http://www.atpturbo.com/Merchant2/mercha...tegory_Code=GRT
we are really buying this:
http://www.turbobygarrett.com/turbobygarrett/catelog/Turbochargers/GT28/GT2860R_707160_5.htm

Which is rated to 360BHP

So that leaves the real GT28RS (Disco Potato) this which ATP DON’T sell:
http://www.turbobygarrett.com/turbobygarrett/catelog/Turbochargers/GT28/GT2860RS_739548_1.htm

but if the specs are the same GT28RS (Disco Potato) and GT2860R then why are the maps different?

So basically when you buy a GT28R from ATP you are really getting a GT2560R
And when you buy a GT28RS from ATP you are really getting a GT2860R

Now that just leaves the Hybrid. Mine is a GT2560R which now has the GT2860R compressor.
So I have a 60mm 62trim .60AR compressor with a 53mm 62trim .64 turbine
So my question which compressor map do I use?

So really the thread should be called GT2560R vs GT2860R because thats what we are really discussing but these damm yanks confused people by renaming turbos.

I run the R/RS Hybrid as well and made 301Bhp using 1.35Bar at PTS when i was in for my remap.

Sean_C was using aquamist and 1.45Bar and got 310.

I think Markus runs about 1.8Bar. <img src="/forum/images/graemlins/shocked.gif" alt="" /> <img src="/forum/images/graemlins/crazy.gif" alt="" />

The most noticable difference between journal and roller bearings is the amount of low down torque you get with a journal turbo.

hmmm on the garrett site the specifications in terms of trim and housing sizes are the same, yet the GT2860R, the one we've all bought is capable of higher airflows?

Joe

It's also worth noting that at 300bhp the thump of the GTI-R at 3000 rpm is hard to control - lots of wheelspin in 2nd gear. With the 28R despite the higher power I now have it comes in more progressively and spin happens at about 5,500 rpm in my case - in some ways this powerband is easier to use - but then the 3000 rpm thump is kinda fun. <img src="/forum/images/graemlins/smile.gif" alt="" />

Personally I'd go for the R/RS hybrid - or the 0.64 RS, but like I said it really depends on how far you want to take the car. <img src="/forum/images/graemlins/smile.gif" alt="" />

<img src="/forum/images/graemlins/love.gif" alt="" /> <img src="/forum/images/graemlins/love.gif" alt="" /> you bet it is, its a 2 hands on the wheel sort of acceleration, damn its addictive <img src="/forum/images/graemlins/laugh.gif" alt="" />