Lithium

It is already a pretty intense result for a smallish trim 76mm compressor attached to a GT30 hotside, to hold 28psi up top efficiently the way it is making power you would have be shooting for around 430 rwkw! I think if you were aiming for that power then I think it really would be time to start considering something GT35 based and a built motor :-)

Discuss? I think we've done PLENTY of that Time to enjoy it.... and I'd like to place a booking for shotgun when I am over for WTAC in October It's certainly a nice change from the GTX3076R which adds the power, but more lag - instead of less Bewilders me that the HTA3076 has been around so long and Garrett could bring out something that doesn't perform as well and have it look like it could become the new black.

That should be a LOT of fun, what fuel etc will you be running?

More on this GT3794R HTA prototype, it is now released as the Super94HTA and apparently spools better than and makes more power than both the PT6766 and the GT3794R HTA... it has been tested on a Mitsi AWD drag car which has run the previous turbos and on a slippery track this weekend it ran 8.4 @ 177mph - huge MPH for a car running a T3 based turbo. So anyone certifiable who was looking for something in the 6766/3794 size range - they are now available to buy: http://store.forcedperformance.net/merchant2/merchant.mvc?Screen=PROD&Store_Code=FP&Product_Code=NTFPSUPER94&Category_Code=Turbo-FP

I think contacting FP is your best option, though they have this page of "stuff" which shows that at the very least provide an upgrade option which they perform. I'd hope you could buy a CHRA too - but haven't looked into it http://store.forcedperformance.net/merchant2/merchant.mvc?Screen=CTGY&Store_Code=FP&Category_Code=Turbo-Upgrade

Lolwat? R34s are the fat ones :-P Sent from my GT-I9505 using Tapatalk 2

It's 11% more pressure at 24psi. If neither turbo are maxed out, then all you are comparing by running at 20psi is spool and then relative setup. If there is a power or power delivery advantage then the odds are it is something in the setup, or the dyno reads higher. That's the only reason I am saying that removing 4psi of boost is missing the point - after full boost has been reached all you are comparing car setup, not turbo.

I know, but running it on 20psi means all you are looking at is response - so what other point is there of him running it at 20psi? A level 24psi does make more sense for a sensible comparison versus 28-24, but any lower than that is kindof stupid if we are talking about advantages of different turbos. His turbo CAN run a level 24psi - if someone else can't or won't, then guts... the advantage to this setup is that it can and has been run to that level and make the numbers it does on that. The reason it didn't do it with the GT3076R is he couldn't - again, he upgraded partly so he could do that. So actually for comparative purposes it makes MUCH more sense for other people to try and run 24psi if you or they want to see the real advantage - R34GeeTeeTee has stepped up to prove what its worth. If others aren't going to or won't prove that theirs can match or better it, bummer. IMHO. Running his at 20psi would just be showing what it would be like if it couldn't run more boost, ie if it were an inferior turbo

Presumably when JEM redid the flex fuel tune they poured straight petrol into the tank to change the percentage down

Running it on 20psi proves nothing - you could think this turbo is no better than the old GT3076R aside from coming on a bit earlier at that boost level. Sure, the 28-24psi spike is going to make the midrange look artificially higher but in most cases that is actually the reason a car with a similar setup will make more torque than another, unless one has a restriction (which CAN be the turbo maxing out). If you want to see where it hits 20psi, follow the dyno plot to that point. Also I am not at all convinced of the hub dyno vs rolling road dyno comparison being equal in this case - when we were discussing this HTA3076 upgrade I investigated lots of JEM's dyno results to get a feel for what to predict the power potential of it as, the numbers which are coming from the hub dyno in this thread and the HG one are often showing cars with stock cams etc making similar or more power per psi than what you would see at JEM's dyno with cams/head work etc. I'd be happy to be proven wrong, as I like to be able to see the wood for the trees and help EVERYONE improve their understanding of everything but I am just calling it how I see it at this stage.

Probably too many levels of extrapolation going on to really tell too much - we don't know how much power one or the other has as an advantage due to varying factors, it'd be interesting to see a comparison with an normal SS2 but I would be pretty surprised/impressed if the SS2 can match it. The 28psi is a peak figure, dropping straight from that point and 391rwkw was achieved on 24psi. To be fair I expect the T67 and HTA3076 to be capable of very similar power, they both seemed to be viewed as around 59-60lb/min turbos so that wouldn't surprise me at all - and yes, the T67 represents exceptional value for money... like anything in this game the extra cost doesn't tend to present a proportional increase in performance, but you definitely to get the higher level. An HTA3582 would probably be every bit as good to drive as the T67, and it sounds a bit like 34GeeTeeTee's is closer to a TD06-20G in response so I'd guess what you are paying for is having the same power with the response of the next size down.

So far I think the HTA3076 has made more than any of the T67s have - I could be wrong, but I haven't noticed any matching 391rwkw on a Mainline or Dyno Dynamics. The rpm readings from the Mainline were a bit hard to work out but could tell that at 4000rpm the HTA3076 had more than the VNT, albeit not massive amounts more (and again the VNT was on a hub dyno) - and the HTA made more power peak... without the risk of having moving parts in the exhaust stream which could fail. Will be interesting to see how Stao gets on with reliability as otherwise it is pretty sweet!

Agree, he has done a fantastic job of choosing parts and people to work with to get an amazing result and generally usable car. I am jealous!

It's not a Kando, there have been turbos I've known of for ages which would match of outperform these but are either more expensive or just not what people in this thread aren't looking for.

If I were to extrapolate from what I have seen elsewhere I would say prepare to see around around 400rpm more lag and maybe up around 460-470rwkw on E85 with the right setup and the end result shouldn't be too surprising.

They are wrong, the GTX is 54.1mm inducer which is almost the same as the HTA3076 (54.8). The HTA3076 would probably make the GTX3071R feel lazy, the HTA3071 would be something else methinks. Sent from my GT-I9505 using Tapatalk 2

After talking to 34GeeTeeTee about his driving impressions the dyno plot doesn't do it any justice (which to be fair I always knew would be the case, but still).... it sounds nuts, I am sure he will make a post at some point on the matter. If what he has said to me so far is anything to go by, then the HTA3071 would be porn for the likes of DiscoPotato and yourself.

FP do a HTA3071 (51lb/min) as well as the HTA3073 you are aware of, there are a few HTA2868s lurking around too. I most definitely do not overlook the HTA3073 at all, I had actually toiled over recommending that unit to 34GeeTeeTee when we first got to discussing upgrades for him which would give him improved response and no loss of power, but it became clear that he'd get a kick out of the extra headroom to go up to the 380-390rwkw (yep - we specifically discussed that power area prior to the tune). The HTA3071 has a 51.2mm inducer, 71mm exducer so is a smaller compressor wheel than the GT3071R - again like the HTA3076 vs the GT3076R, so you would be looking at something that would make power somewhere between the GT3071R and GT3076R but be stupidly responsive.

Yeah if you put much stock in virtual dyno we were seeing ~220rwkw at 18psi on BP98 with the PE1420, quite a lot more on E85... very impressive turbo, but it failed. The TD05 definitely flows more, can already tell at this stage. I don't know that spool will improve drastically.

Got the TD05H-16G installed and running on the car today - went out for a quick road test, on wastegate boost the "1bar actuator" actually held 11psi with no adjustment. With boost control set up it made 18psi by 3700rpm on the SR20, which is pretty much as expected. About 400rpm laggier than the PE1420, but runs 1psi more boost with the same wastegate setup and certainly feels like it has more "grr". Seems like a great match for what is expected of it

I'd like to take this opportunity to say BOOM! headshot. Can confirm the above setup is capable of 20psi by 3700rpm and 391rwkw, so plenty of change - courtesy of R34GeeTeeTee doing everything mentioned bar the built bottom end, and E70 instead of E85. I like being right, especially when I would look like a right douche if I wasn't See the attached dyno plot - has his 360kw GT3076R result to compare with the new HTA result, the old faithful GT3076R has no answer for the HTA anywhere.

Here is R34geeTeeTee's new FP HTA GT3076R results overlaid with his old GT3076R result shouldn't need to explain which is which So people have targetted 200rwkw by 4000rpm as being a benchmark for a good street RB25 - this exceeds that by over 30kw, and manages to also supply 390rwkw on 24psi. Where's that cake?

GT3076R vs HTA GT3076R... shouldn't need to explain which is which

I have been saying it for years now, but I will say it again - I think the GT3076R HTA from Forced Performance is practically made for an RB25 without it being deliberate. Christ, where do I start listing the advantages over the typical choices used on RB25s. Lets use the cast wheel GT3076R as a comparison, which is proven overall to be a good match for a stock RB25 road car to all but the scarediest of punters: - 56 trim GT3076R compressor wheel is 30% heavier - HTA should give better transient response, less load on the engine exhaust to drive the compressor which can effect EBP and therefore safety for engine, turbo, and potentially help power - Smaller hub (several mm) / thinner blades mean more air moved through the same surface area. ie, more airflow for an given aero design, more air moved for given shaft rpm (more + for response here), just generally better for moving air. - Better aerodynamics, basically can help response (building boost pressure) and flow - Bigger compressor cover with some sneaky porting (so I am told) to help with the efficiency theme - HTA compressor wheel has a smaller inducer, lower trim - aka better surge resistance, better spool for exducer size (ignoring mass and aero) - HTA compressor wheel exducer is no larger (vs GTX and other power upgrade options) which means that the whole rotating assembly can potentially get to higher rpm without certain speed of sound related issues which impede flow, also the higher speed the compressor can spin to the higher speed the turbine can spin to, which effectively increases the turbine efficiency Net effect is a turbo which on a dyno should show AT WORST no more lag over a GT3076R (potential for less) under steady load and a transient response more like a cast GT3071R, which can flow more like a GTX3076R and have a turbine which can effectively flow (due to the combination of the bunch) better than a GT30 would with an inferior wheel match. 20c says that as soon as someone FINALLY gets one on an RB25 and a decent tune on it, whether it is just a stock RB25 with basic boltons, or a full house one pushing the thing hard - it will be a very decent result.

Good to have people around who are willing to try and test combos so you know what works Your car has become a bit of a benchmark for the GT3076R's ability, I reckon!