Turbonetics Gtk Series

[STATUS]

Yeah, it's certainly not the most responsive of things but has held up pretty well for me thus far. I've been hanging to get i tuned with the 2.2 as we were only able to do a run in tune before the manifold gave way, but with that it was doing 225rwkw's at 14psi and was making 20rwkw's more at 3900rpm than it was with the 2l, and 20rwkw's more at 3200 despite the big cams. I'd like to find out what it's limit is, but some niggling problems have kept me from it so far.

I remember having Athid's 180 on the dyno and mine on the same day, and the curves were quite similar and power similar too. Interestingly I'm making 30rwkw's more at 3910rpm than the 312rwkw L2 dyno with the 264/172 combo, but Athid's S15 dyno creams it at the same RPM by around 30rwkw's!

Ikeya formula goodness.... if only i could afford one.

[juggernaut1]

The only problem with the 3076 TS is that the .78 A/R TS housing is becoming challenged for flow. Hence this is the reason Geoff Raicer is recommending the 3071 to Dane (as he recommended to me) as it provides the best transient response but also the comp flow is more compatible to the ex housing flow. Users of the 3071 setup that have switched to the 3076 setup have reported more mid and top end, but its not mind numbing but "noticeable" from the seat of the pants feel as reported by those who've done the upgrade - although I have yet to find a back to back 3071 and 3076 dyno comparison with a TS .78 AR ex housing - I might be the first.

Due to the limited TS ex housings for this size Garrett turbo (although I did manage to find myself a used .82 TS A/R) - I suspect this is the reason Geoff is now recommending the BW turbo's as the GT30R equivalent is available with a .85 TS A/R.

As for traction - I'm running 290rwks (TS 3071) with sydneykid suspension coilover kit on my s15 and I'm impressed with the way the car get its power down from 2nd gear on with the TS setup - however, I suspect the short runner Hypertune intake might be dulling the mid-range and so help traction in this regard, whilst extending the rev range.

[STATUS]

Int gate SS gt3071 and gt2871 @ 20-21psi on 2l sr20 both big lift 264's. GT2871R would not reliably make any more power even at more boost. GT30171 was a new engine so customer had specified a limit of 20psi, no doubt at 22-24 psi is would have made more torque and cracked 315-odd rwkw.

[Lithium]

Wow, 308kw is really good power from that turbo - imagine that with a TS setup the spool should be not far off the GT2871R too!

[discopotato03]

Actually thinking about it Garrett are doing both the GT3071R and GT3076R in Evo 10 specific TS turbine housings and last time I asked him Geoff was impressed with their design - except for the gate issue .

They are being cast and machined up in I think 0.73 and 0.94 A/R ratios - AND they're designed for an 84 trim GT30 UHP turbine not the diesel GT32 turbine like the 0.78 one is . An expensive option but a Garrett Evo GT30 housing with the gate sealed shut and external/s may be another option .

I know you won't go the GtiR throttle system but just remember this , Nissan wanted that AWD Pulsar to be the Rally spec go getter and had the body and suspension been better thought out it could have been a lot better than it was - weight distribution and cooling issues were biggies though .

With Rally throttle response is everything because when you flatten it often it means living or dying at the bleeding edge . The ITB's give you more of everything everywhere meaning torque and the point I'm making is its engine torque to get you cracking , it doesn't matter weather the torque comes from better breathing or a small turbo but having a tight leash on its delivery makes a huge difference .

Really everything you are trying to do is tied to making good controllable torque over as wide a range as possible . Multiple throttling is effectively trying to do what twin scrolling is doing on the hot side , minimise interference from adjacent cylinders only this time its air going in instead of exhaust going out .

Where you win is that you have very accurate control of airflow where having accurate controll of turbine speed is very complex and difficult to nail .

Nissan were not stupid when they put the RB26 together and like the GTiR engine was aimed at homologation for competition cars . The 26 gets ITB's for very good reasons and the twin parallel dryers very closely mimic a twin scroll single , the twins make wastegating a snap on a production car and as we know don't work too foul on a real race car either . Imagine what a GTR would have felt like with say the BB VG30 single turbo and a plenum manifold with a single throttle body on the front .

Really volumetric efficiency is everything and the higher it can be over as wider engine speed range as possible is what its all about .

Please don't think I'm being negative but an SR20 in no exercise in engineering exellency , it achieved what Nissan wanted from it for a time but it is VERY much a compromise of a two litre four that can fall in length wise or cross wise (block length/height/bore size limitations) and a head that isn't really a hi speed thing valve train wise . There are going to be limits on how much capacity you can economically squeeze in because the block length and the rods short . So I believe the way to make them work is go for every VE advantage you can to get the most torque you can from them without turning huge revs . I'm not so sure the aluminium makes an SR20 light , I mob I knew roughly weighed a nude SR and an FJ20 and - the difference wasn't as much as they expected it to be .

Everyones going to have their brand loyalties but being the sl*t that I am parts wise I think theres a lot to like about Mitsys 4G63 turbo engine , Geoffs had amasing power out of those things .

Roy I know what you're saying about the AWD's making reasonable steerers look better but honestly 4/AWD can create nearly as many problems as it solves so need to be a super pilot to get the best from it .

A .

[badhairdave]

Out of interest, what have you put together lately disco?

[phunky_monkey]

Thanks A. If I were to do it again I may have decided to go down that route. Honestly I'm being stubborn with the plenum for a few reasons, but mostly because of the headaches I went through to get the thing on the car (12 months after ordering!) and dammit I want to see it work!

If I could do it over again I may have, but I want to see how it goes first. I understand that this is going to have an effect on the bits hanging from the other side of the engine but I'll take that into account.

I've actually just been chatting to Geoff and now I'm in a quandry. I'm pretty sold on his kit but am tossing up the 3071R TS or the Airwerks S200 TS with a .85 housing, and maybe the .76 housing sent too so I can test both (Geoff says they're relatively inexpensive, and the money saved over the 71 may make it worthwhile). The T3 S200 is untested by Geoff as yet, but the BW guys promise good things and he's inclined to trust them. Someone has to try it I guess, and as I'm such a big fan of the Blitz stuff then maybe it should be me... Geoff is recommending the 3071 as the quickest spooling of the bunch, but would definitely choose the BW over the 3076. As I wasn't sure between the 71 and 76 the BW may be something nice in between.

The S200SX was thrown into the mix too, but as it's a T4 I think it may limit my options if I don't care for it.

Trent: Great power production from the 3071 int gate. In Twin scroll form Geoff has seen 150rwkw's by around 3300-3400rpm, so definitely could be the best option.

[juggernaut1]

Dane,

I think you've sort of answered your own question.

Choose TS 3071 with .78 for the best transient response turbo. I can assure you it will haul out of corners and give you good a broad rev range. You still need a delicate right foot out of corners but it has a nice linear power curve which makes the car controllable, predictable and best of all easy to drive. Think of it like driving a n/a V8.

If you wanted more power than the 3071 I would go the TS BW200 (which is actually the BW256) over the 3076 with the TS .78 A/R. Looking at the compressor map IMO you will make more power out of the BW 200 over the 3076 as it flows a bit more air and is also more efficient at higher boost levels if you wanted to turn up the wick.

URAS: thanks for sharing the various dyno's as well.

Disco: No rose coloured glasses here re the SR20.....but still not a bad little package.....although valve train could have been better.

Edited October 20, 2009 by juggernaut1

[Lithium]

Borg Warner S256 dyno plots I've seen haven't impressed me that much to be honest, the problem is you don't always know how well things are working on any setup. I'd definitely sooner go a GT3076R than one!

[phunky_monkey]

You're right Ian, I have indeed answered my own question but now it's determining exactly how much I want and what compromise I'm willing to suffer. The 3071R is leader of the pack so far, but I guess it's my curiosity about the BW, as well as the positive reviews that's pushing me to try it out. Where did you get the info that it's a 256 from? Is it the same part number? It does look to be the same.

Lithium: I'm not going to go the 3076R TS I don't think, the 3071R and BW options seem to be shaping up as the turbo's of choice on the Full Race setup. The TS versions have not been compared form what I can see.

[juggernaut1]

You're right Ian, I have indeed answered my own question but now it's determining exactly how much I want and what compromise I'm willing to suffer. The 3071R is leader of the pack so far, but I guess it's my curiosity about the BW, as well as the positive reviews that's pushing me to try it out. Where did you get the info that it's a 256 from? I haven't seen much info on it. Is it the single scroll?

Geoff Raicer re the s200 = s256. This turbo can be spec'd in single scroll (with traditional or misubishi ex housings) or twin scroll. I think there are two ex a/r in the twin scroll with .85 being the largest. From memory the BW has a bigger ex wheel than the 3071/3076 too.

Late clarification: the s200 is the twin scroll version and the s256 is the single scroll version..... just different naming for the same turbo but with different ex housings.

Edited October 20, 2009 by juggernaut1

[badhairdave]

In Twin scroll form Geoff has seen 150rwkw's by around 3300-3400rpm, so definitely could be the best option.

Got dyno sheet? Thats very impressive. Mines only just starting to climb past 100 at that point

Better than factory power at half the revs

[phunky_monkey]

I don't unfortunately Dave, but I was pretty damn impressed to. Though US dyno's seem to show more power than ours from what I've seen.

Ian: Cool cool, thanks. The S200SX T4 is the slightly smaller option also, but the T4 turns me off a bit... and it' unknown whether the .76 will work well in this application with the S256... hmmmm. All these numbers are hurting my brain

[juggernaut1]

Geoff suspects the 74mm T3 turbine wheel is more efficient than the 70mm T4 turbine wheel. So T3 sounds the way to go.

Edited October 20, 2009 by juggernaut1

[Lithium]

You're right Ian, I have indeed answered my own question but now it's determining exactly how much I want and what compromise I'm willing to suffer. The 3071R is leader of the pack so far, but I guess it's my curiosity about the BW, as well as the positive reviews that's pushing me to try it out. Where did you get the info that it's a 256 from? Is it the same part number? It does look to be the same.

Lithium: I'm not going to go the 3076R TS I don't think, the 3071R and BW options seem to be shaping up as the turbo's of choice on the Full Race setup. The TS versions have not been compared form what I can see.

Yeah I know what you mean, GT3071R sounds like the best for what you are after- but if a BW S256 was an option I'd put it 3rd to the GT3076R.

Managed to dig out a GT3076R and S256 back to back on the same setup, details of each turbo etc is clearly available so you can verify there is nothing unfair to hold the S256 back like what some of the BW sellers have been known to do when comparing theirs to GT-BB turbos.

Solid line = GT3076R, dotted line = S256.

Thread here for all details:

http://www.honda-tech.com/showthread.php?t=2220363

[STATUS]

Got dyno sheet? Thats very impressive. Mines only just starting to climb past 100 at that point

Better than factory power at half the revs

its all in the ramp rate, i would like to know the ramp rate for a car to make that sort of number.

[phunky_monkey]

Lithium: In the same scenario Geoff Raicer puts the 76 in third position, stating he'd definitely choose the BW over it... I did read that thread earlier this morning, but it's not a true comparison to what I'm after. However it is food for thought, and the response is not fantastic. It is a fair midrange loss to the 76.

Dave/Trent: On an old test done by yourself Trent, the T518Z 8cm made 150 by 3400rpm. Geoff thinks the 30R kit will have the same response with more top end on my engine. I'll ask for a chart

[discopotato03]

A couple of things go against both the GT3076R and the GT3582R in their usual form . Firstly the turbine housings are not twin scroll and secondly the turbines and compressors in both cases are usually big trim sizes . They do quite well with big A/R turbine housings on them but thats not the way to go about making them responsive in the lower mid range . There are very few options with both of them and in most cases they are only compressor trim sizes ie 48/52/56T for the GT3076R and available from other GT BB turbos 50 and 54T for the GT40 compressor .

Garrett has changed their thinking with turbine trim sizes but ATM thats only really available on the GT37xxR and GT4088R turbos , 78T instead of 84T .

I had a quick sniff around some BW turbo specs mainly because Geoff mentioned a while back that some of their turbos are doing better than some GT BB Garretts and are cheaper to buy . I suspect that BW are using reasonably big diameter wheels in those turbos with big A/R turbine housings but with smaller trim sizes than most of Garretts GT series units .

I guess the theory is big diameter wheels for large diameter diffusers and nozzles and with small/med trim sizes (inducers/exducers) to pick up efficiency and response . With big A/R housings it does make for a larger overall unit but if thats what it takes ...

The small frame Garrett GT's (GT2554R-GT3582R) I think were intended to be as compact as possible as well as being a generation ahead of the T25-T04S range .

What have I built , very little with my own hands because I have no workshop at home and revolving shiftwork makes it difficult at times .

My old Subaru daily is a far cry from what I drove home from Melbourne two years ago . Its now AWD with close ratios and I dug up the highest spec variant of its engine in this land and had it rebuilt . Coated pistons/head porting/256 deg NA cams/bigger exhaust/massive anti roll bars (thanks SK)/Koni rear coil overs/five stud hub kit to fit which basically puts me into Impreza brake and wheel territory . The 13x5's will be replacede by 16x7's and the matching brakes from a MY00 Rex .

Next on the list is an exhaust header because the factory one is garbage as is the tiny RHB52 VF2 turbo . I had GCG build up a spud spec turbo thats basically a GT2860RS but with the smaller GT2554Rs compressor wheel and housing and the smaller 0.64 turbine housing on the hot side .

I still have to buy a wire in computer to replace the AM radio the engine lives with ATM and I'd like that to be a ViPec V44 , just waiting to see if they can do one for me with high current injector drivers . Then I can use FJ turbo 360cc squirters to replace the little 240cc std ones . Fuel pump was changed for a VL turbo one .

My R33 hasn't got past the PFC and 34GTt IC yet but I had one of the Woolafs old heads ported and larger exhaust valves fitted by Harris , has Poncams in it too .

GCG managed to get me a 52 comp trim GT3037 from Japan and the plan is to hang it off a HKS cast manifold I've had for a while . I've been talking to RIPS about a modified RB25 lower manifold modded to take GTR ITB's and hopefully into that will go a set of Nismo 740's I have too .

Fingers crossed someone still has the R34 GTR IC for it and eventusally it will go in to .

Recently the flywheel was lightened and Jim Berry did me a clutch for it which is really nice to drive .

My 33 came with fresh SK type Whiteline/Bilstein suspension and a set of 17x8.5 Rays wheels and I had Michellin PP2's fitted so it points quite well .

So lots a bits and lots to do , A .

[juggernaut1]

Thanks Lithium for that link re s256 vs 3076. The following spec's are lifted from that link:

Here are some measurements I took of the turbos:

Borg Warner S256:

.50 A/R compressor housing

Compressor Inducer 56.0mm

Compressor Exducer 85.95mm

Turbine 75-76mm (odd number of blades couldn’t put a caliper directly on it just a ballpark figure)

Turbo with .70 A/R 4 bolt housing: 21 lbs

Turbo with .85 A/R 6 bolt housing: 23.2 lbs

Garrett GT3076r

Compressor Inducer 57.0mm

Compressor Exducer 76.14mm

Turbine 59.90mm

Turbo with .63 A/R 4 bolt housing 15.0 lbs

Turbo with Tial .63 A/R v band stainless housing 11.2 lbs

Now I just had a look at the BW S200 specs and this is what I find (based on my conversion from inches):

Compressor Inducer 56 mm

Compressor Exducer 80 mm

Turbine Inducer 74 mm

Turbine Exducer 65 mm

So my earlier suggestion that the S200 = to S256 (based on comments from Geoff) are not correct unless the specs on the 256 have changed since the tests in the above thread link were done.

Therefore, compared to the S256 (in the above test with the 3076) the S200 has the same comp comp inducer and a smaller comp exducer by around 6mm. In other words the s200 has a smaller trim comp wheel with what would appear to be the same size exhaust wheel of the S256. But the s200 still has a bigger comp and possibly turbine wheel than the 3076.

So the S200 would be a more responsive turbo compared to the S256 and then add twin scroll on top of that and it will be more responsive again. More responsive and power productive than the 3076 in TS format...quite possibly.

Edited October 20, 2009 by juggernaut1

[T04GTR]

dont be afraid of non ball bearing.

one thing not mentioned is boost pressure between the bw and garrett. but who runs 35psi on a track car anyway

il be testing my bullseye s372r soon.