Lithium

Not sure what I think of the GTX2867R and HTA2868, both very high flowing compressors for the GT28 hotside - probably not bad things, but the GTX2863R kindof excites me more when looking at the match to the turbine, and also the flow for it's size - given it is a legit 44lb/min turbo with only a 63mm exducer. Like the other two turbos, I don't really feel any of them have much of a place on an RB unless perhaps you are slugging it out with an RB20. The only place for GT28 turbines with RBs is if you are putting two of them on, imho. The HTA3071 would be a lovely beast if response is your first and foremost target - a .82a/r twin scroll one would pretty much be craziness

Holy crap - make an effort.

Was just discussing this car last week with a mate too - there was hype about a come back but it never happened, would love to know if there was anything further or if anything still exists. Maybe Heat Treatments wrecked the fun?

Yeah 375+kw from an HTA GT3076R - check out the back to back of a normal GT3076R to the ForcedPerformance HTA done by 34GeeTeeTee in this thread: http://www.skylinesaustralia.com/forums/topic/426059-forced-performance-hta-turbos/ - better than the GT3076R in every way, basically the ultimate RB25 turbo upgrade at this stage Bush bearing isn't more reliable, just much cheaper to rebuild when they do fail.

You reckon that much? I would have thought it would be that WITH the housing

That is on 98? And RB30? ;-)

Get a Super94, do both? ;-) Sent from my GT-I9505 using Tapatalk 2

Whp? What kind of dyno? A few variables to consider there, including setup etc - 550whp definitely getting up there but within the realms of possibility. Would expect you would need solidly in the 20psi range to do that, so I would guess full boost in the low 4000rpm area though all dependant on how the setup is done and how dyno reads etc. Sent from my GT-I9505 using Tapatalk 2

http://www.nissanroadracing.com/showthread.php?t=3297

You won't find it or get it in this thread - go the Hypergear thread if you want to see that. I will chase up a guy I know with an HTA3073 on his SR, will see if he has got any further with that Sent from my GT-I9505 using Tapatalk 2

Yep you definitely have to take indications from what someone says when they drive the car too, having done road tuning on cars with TD06SL2 turbines I have a reasonable idea of what to expect - you take it all into consideration, I was far from calling the SL2 setup laggy - more so saying that a BB HTA71 would be VERY responsive. Remember one of 34GeeTeeTee's points of note he had about his car is the dyno did not do justice the way the car drives and responds, so far. Given his made around 50rwkw more on a rolling road dyno with a better boost curve, that bodes well even if you choose to believe that something has happened which exaggerates it's performance. This kind of thing (dyno not doing the real world response proper justice) will often be the case with these turbos running light billet comp wheels compared to traditional units - same goes for comparing journal bearing turbos with BB cores, BB turbos show their best when driven in the real world versus on the dyno.

Sorry I misinterpreted your last question, I thought you were talking about purely Garrett based HTA turbos - not alternatives to FP based hybrids. That isn't a bad result, response isn't bad for a journal bearing turbo making that kind of power and gives an idea of what a billet 71mm can potentially do. I have no reason to think the 71HTA would make any more, or less power - though I'd expect a HTA3071 to come on a fair bit better than that, so maybe my previous call (depending on if it is true that this dyno does read like Mainlines/DDs despite this forum saying for years Dynapacks are inflated) should be adjusted to say a VERY responsive 340kw+ would be realistic.

Not at all taboo - the HTA wheels are the main point of this, and I have thought the same thing myself. A TD06 SL2 HTA71 would be very very interesting thing on an RB25 (imagine it with a BB core!!!), And yes, I also follow the Kando results - I just didn't venture into that kind of range as there is no freely available option at this stage, I think we've even mentioned to Stao (or that it would be good if he could) do a hybrid of sorts using an HTA wheel. Now FP are making their own BB cores, wonder if they will look at doing "universal" non-Garrett based HTA BB turbos - the new Super94 sounds like it may be a first of that kind of thing, and the results are nothing short of phenomenal... if the reports are accurate it almost does to the PT6766 and old HTA3794 what R34GeeTeeTee's HTA3076 did to the old GT3076R: ^ That is on a T3 flanged HTA Super94

.63 IW HTA3071 on a stock block E70 RB25? Hard call. Maybe 330rwkw, with ridiculous response? Very little to work with on that one, but that's the first area that comes to mind for me. I'd expect it to be giving a very solid push in the back in the low 3000rpm range, too.

Yeah they are definitely bulkier - though the T04E housings aren't exactly tiny, all R34GeeTeeTee's needed was intercooler piping upgraded in size which isn't a packaging issue so much as it just was a change from one compressor outlet size to another. These turbos are the same size as GT3582Rs etc, which have been mounted in all kinds of ways - included on stock manifolds on RB25s so I doubt it would be much more than a pain in the butt to install. If I had to be honest, my confidence in the 71HTA being good for an RB25 is not enormous - not to say it wouldn't be, but that compressor is usually used as an entry-ish level bolt on for EVOs and while the response is insane etc, they all seem to be pushing a reasonable amount of boost to make reasonable power. An HTA3071 on an RB20 with a .63a/r housing however would be ridiculous, I'd say they'd be EXCELLENT for each other. Going by R34GeeTeeTee's response etc, I'd say there is no point going smaller than the HTA3073 - that is a fairly decent step down in size from the HTA3076 and you'll definitely feel the difference, but it still flows well. It should make for quite lively acceleration in all cases - the HTA3071 would probably fit very well as a GT2835 or GT-RS upgrade with minimal (if any) compromise in spool/response but how much more power will available to be made in the 15-20psi range which should on paper be the top range for that turbo size... I don't know. If I *were* to try the HTA3071, I'd be tempted to use the .63 housing - too... which is a bit unlike me, but given how fast it will come on and how high speed suited it will be, not to mention the fact that I actually suspect that while it is rated to 51lb/min it will flow a reasonable amount less than a GT3076R in the 15-20psi range it'd be used for. I reckon a setup like that would be very VERY responsive and not have the nasty EGT and backpressure issues the GTRS etc have. If the compressor starts maxing out it will be easier to manage, especially on pump gas. I am not really convinced that using E85 to mask excessive exhaust pressure means that you are making it better, so much as allowing power to be made while still thrashing everything ultra hard - I'd not expect awesome turbo etc life doing that.

It's a bit hard to read - so to be certain what I ended up doing is working out that every vertical line represented 185rpm... which makes the line that 280rwkw intersects is the 4070rpm mark, which is why I used a loose number. 4000rpm, or 200kw are a bit hard to determine the value from the opposite axis from exactly.

Ah yeah I can agree with the FP Red/Black etc - though they aren't far off, the compressors are the same and there is debate on what works better all around... David Buschur felt the GT3076R HTA performed better than an FP Red would in his case, though he was using a TiAL housing on his and a very serious motor etc. The main purpose behind the FP Red/Black etc is they are direct bolt on units for EVOs, if FP thought the wheel/compressor combo could be better for the "universal" versions there is a good chance they would have made them with them. Maybe they still will...

In regards to the dinosaurs - they have done well, and still do... a lot of FP turbos make good use of proven Dinotech - plenty of it does great! There are lots more than just that result which prove that the HTAs work very well, just this is the first on a Skyline with a back to back with an equivalent and well known Garrett which brings things closer to home. It seems there is no winning. Here is a turbo which makes excellent power with excellent response, and there are people wahhing that it isn't doing much despite it doing it ALL better than one of the best choices for an RB25. Either the extra power doesn't count because most people wouldn't push it that hard, or the result isn't that stand out because it is making similar to a relatively cheap (but way laggier) turbo. 200kw by 4000rpm for some time was seen as the standard target for an awesome match on an RB25 - ignoring the fact that the target for this turbo is more transient response than building boost at specific rpm, how many other RB25s are making 280rwkw near that mark? What mods would be required to get an RB25 do that and pull 390rwkw on the top end with a budget turbo? And on that note, you guys also realise we are talking about just the turbo - and not saying that going to an HTA replaces all other mods, like anything it can be added to the list to develop a result?

Indeed - the GT transient response being better than the GTX seems to be a recurring theme, so treating the GT as a control - the case seems to be: For the size it seems to be: GTX - Flow comparable to the next size up compressor, responds mid way to the next size compressor HTA - Flow almost comparable to the next size up in compressor, responds mid way to the next size down compressor In the case of Mat's HTA - if he turned his boost down to 16psi, I'd say the curve would look much like a GT3071R equivalent - but then at 20psi it makes power like a full GT3076R... and THEN you keep turning the boost up and realise that it will make power close to what you'd expect from an 82mm GT-series compressor! This is why they make so much sense to me, you can go with the HTA3076 whose compressor behaviour looks like it perfectly matches the point the GT30 hotside limits - there is no wasted turbine or compressor flow, so heaps of power potential BUT not fully utilising it means the worst case scenario is you make GT3071R power with GT3071R spool, or if you want- GT3076R power with GT3071R spool. If you were never going to get silly, then you could go with a GT3073R and make GT3076R power with better response than a GT3071R - who knows what that'd feel like!

As mentioned earlier in the thread, the GTX tend to spool at best the same as the equivalent GT - but really they usually are laggier. The HTA tend to respond better than the equivalent GT. Both tend to make ~10% more power, give or take. The GTX are often a little more aggressive flow wise than the equivalent HTA, but that would partly because they are bigger trim and generally larger compressors - which is also part of why they tend to be a bit laggier. So far the general consensus from people who have built cars using both combinations have preferred the HTA. The HTAs (and GTX) have been used heaps on GTRs, so a bit of experience in that world - this thread should give a bit of an idea from some of the big names in R35 tuning: http://www.gtrlife.com/forums/topic/79848-gtx3076-vs-hta3076both-has-63-ar/

I would love to do a build too, time and money are a challenge - and I get quite a bit of a speed fix playing with other peoples cars Will see how the next few months goes though, starting to get a bit restless and have accumulated a few ideas

Nah, haven't done much with my own car in years. This is the closest to a build thread I have from way back when GT3076Rs weren't common, and nothing to do with these turbos - http://www.skylinesaustralia.com/forums/topic/189495-rb25det-with-a-real-82-ar-gt3076r/?hl=+gt3076r Sent from my GT-I9505 using Tapatalk 2

Probably not, same hotside and no other changes in the setup. The GT made the power so clearly was able to flow the air to do it, so the odds are the only difference will be the HTA spools and responds better. There is the possibility the HTA may hold better power after peak is reached however. The only reason in this kind of comparison that one would make more than another is if the turbo can't supply the air that the engine wants. So no more peak power, but in the real world a faster and nicer to drive car as that same power is more easily accessible - and done with less stress as it has much more in reserve ;-)

Are those two setups exactly the same turbo? Probably irrelevant, GT30s and TD06s are quite different beasts - an RB25 (let alone an RB26) with a .82a/r GTX3071R would make an RB20 with a .63a/r GTX3071R look silly at every point in the rev range, I'd put money on it. I'd strongly suggest the .82 over the .63 in this case, personally.

Yeah that has been a bit of a negative for Garrett based turbochargers for a while, however Garrett do proper T4 twin scroll exhaust housings for GT35 wheels now - so it should be quite doable A friend of mine has an HTA3586 with the ATP T4 housing in his new GTR and that is going to be a bit of a monster, too. Should be hitting the rollers soon with a new upgraded fuel system and E85 - I expect it will be fairly silly! Should be able to report results soon. The same engine/turbo setup was previously in an R32 GTSt and not E85 but met a sticky end: