Lithium

Yeah for sure, have played with all of them to see the general trends on them - we've had pretty consistent results with DIN which is the main thing I am worried about. Because enough has been mentioned I decided to recalculate the peak numbers mentioned to SAE J1349 correction, peak power would have been 241kw in the dyno plot shown above and on soft timing when it crept out to 20psi we saw just over 260kw. How do those numbers fit with what you'd expect? Will try and get another dyno run with it when we work out what has caused the random onset of boost creep, and try and get an SAE J1349 corrected run.

not to be rude or nitpicking but that dyno is using din (american scale) which gives higher readings. should be on SAE2004. It gives higher readings than some of the dynos over there, yes - but it is what it should be as it is what we have been using for years and what we are used to. If I had completed the tune as I wanted etc without time and patience constraints then I would have pissed around with getting another print out with a different calibration for the benefit of people here but I figured that given the difference between the corrections is not huge and the main purpose was to show how it comes on etc I figured it would be still interesting to some.

Here's a plot from the tuning with boost about as stable as we could manage:

This turned out to be a very frustrating day on the dyno - after doing plenty of testing on the road before booking the tune etc, the thing decided to be a dick on the dyno and we lost a good couple of hours trying to resolve a major boost creep issue that we had never seen before. We ended up giving up on doing that with paid for dyno time (quite hard to secure a booking for this kind of thing) so we decided to try and make the best we could of the situation, which ended up being able to hold roughly 16-17psi up to 5800rpm and then try and get the boost control sorted later, then just tidy up the last bits of fuelling on the road as the main purpose of the dyno was really to get a picture of what timing the engine wanted on a variety of different loads and ethanol blends - which we achieved. End result on E77 was 250kw @ 5800rpm running about 17psi with full boost at 3500rpm on a 9 second run which is pretty decent, I reckon. Power was still climbing with more rpm, so if we could have held 17psi the full way it would have made more than 250 at that boost level... and it was also very keen on power gains with more boost. We saw over 270kw on 20psi with soft timing at just over 6000rpm before we gave up on trying to tame the boost control, so there is plenty more power in this setup. Unsure at this stage whether the issue is a Kando Dynamic quality issue or if something else in the setup decided to be funny, will update if it turns out to be a Kando fail however it must again be noted that the car never previously had a boost control issue - though it does sound like it may have developed a few days before the dyno and at the time the owner thought nothing of the cut out he experienced thinking it was something else.

Lol wow, oops

Had a little lol at the idea of a single -9 on an RB26, that would certainly be responsive and 'make power'

Err, no? The different colours are hp, torque and boost, it's just a new 6262 versus and old 5857 in that comparison.

You really are terrible at this, work with us - read our answers and answer the questions you are asked properly, I have no idea why some of us are still bothering. What fuel will you be running?

He said hp, not kw

So you've not really given us any of the input we've asked for in order to make sure you're given the right suggestions, and not paid attention to the recommendations we've offered - then mentioned a different option to what anyone here has mentioned with no "why"? Why does this thread exist, again?

Does Chequered have any GT3582R or GT3076R on a stock RB25 from that dyno to compare with? It'd be really interesting to see the difference, looks like an awesome result - nice work Be interesting to see how they go on pump gas, too!

Yeah that is not what those turbos would be comparable to, they are much larger compressors than -5s and higher flowing for their size so while the lag may not be as bad as the increased size might suggest, it will still be quite noticeably laggier but they will also punch seriously. Definitely a big single is the way to go for that requirement, there isn't really anything in the modern billet brigade to fit that small a requirement. There are 55mm HTA compressors but not sure that they are intended for GT28 cores and their flow is likely to be more like -9ish and better response if they could be used so too far the other way. The EFRs start at 62mm and likely to end up -5ish in spool

There is a guy (mentioned this stuff recently in this thread) on the UK forums that installed a pair on his and from memory it had no surge issues or anything, but his engine failed before he managed to get a full tune into it If the compressor doesn't choke on the turbine or smaller compressor cover (not convinced it won't) then I'd peg it to be capable of outflowing -10s and spool somewhere between the -5s and -10s. Hard to say though

There is an option, I'm just not certain how good it would be - Owen Developments in the UK do a few custom FP based combos which FP themselves don't release to address customer requirements in the UK: http://www.owendevelopments.co.uk/article/76/NEW_Skyline_R33-34_twin_GT2668_HTA_turbos/ They've also sold HTA4094R turbos and if I remember a couple of other interesting HTA based units which I am fascinated that FP themselves don't market.

Wow that curve is pretty awesome - man a twin scroll HTA3076 would make for an incredible street RB25 setup, next step for Owen's car? HTA3582 would be just nuts, probably similar response to a normal GT3076R but good for nearly 100rwkw more haha

Hard to say, really - probably be quite noticeably laggier, and going from Bri73y (396rwkw with a VERY free flowing exhaust and stock GTR intercooler) and 34GeeTeeTee (391rwkw with reasonably quiet 3" exhaust + screamer pipe, good FMIC)'s results the compressor and the .82a/r turbine housing are getting to their limits in parallel - so upgrading one end or the other may not give very rewarding results. A 1.06 housing could potentially cause lag that I am not convinced would be justified - it would be an interesting thing to see, but it wouldn't be a thing I'm go out of my way to recommend people try as I'm much more confident that the HTA3582 would offer a safer more acceptable balance of spool and power. Bare in mine the HTA3582 is likely to spool much like the stock GTR turbos (the HTA3076 better than stock) so really makes it hard to end up with a disappointing result, so long as you aren't looking for over ~400kw on pump gas or ~450kw on E85... as thumbsucks. Your thoughts? Sent from my GT-I9505 using Tapatalk 2

Hard to say, really - probably be quite noticeably laggier, and going from Bri73y (396rwkw with a VERY free flowing exhaust and stock GTR intercooler) and 34GeeTeeTee (391rwkw with reasonably quiet 3" exhaust + screamer pipe, good FMIC)'s results the compressor and the .82a/r turbine housing are getting to their limits in parallel - so upgrading one end or the other may not give very rewarding results. A 1.06 housing could potentially cause lag that I am not convinced would be justified - it would be an interesting thing to see, but it wouldn't be a thing I'm go out of my way to recommend people try as I'm much more confident that the HTA3582 would offer a safer more acceptable balance of spool and power. Bare in mine the HTA3582 is likely to spool much like the stock GTR turbos (the HTA3076 better than stock) so really makes it hard to end up with a disappointing result, so long as you aren't looking for ~400kw on pump gas or ~450kw on E85... as thumbsucks. Your thoughts?

^ nailed it :-D

You've effectively regurgitated what you said on the first page - who knows what you mean by power and response. Some people get the giggles off 240kw @ wheels, some people can happily live with full boost at 5500rpm. Get a GT6041, it will make some power and will respond eventually. I stick by my initial suggestion, anyone who isn't keen to commit on EXACTLY what they are after but want something quick and streetable then I reckon an FP HTA GT3582R would be the perfect thing for an RB26 based GTR. Should be good for 350+kw on pump gas or 400+kw on E85, and good boost by 4000rpm.

I even asked you to On that note, DYNO PLOTS???!!!

Because going to a bigger single is winning - and it seems people are more keen on winning these days Twin scroll HTA3586 would go nicely!

What do you have for it currently

What would be nice would be an HTA equivalent of -9s IMHO, something that flowed a bit more than -5s but spooled better than any low mount bolton option currently available. Wonder if the would bite :-D Sent from my GT-I9505 using Tapatalk 2

He's a tinny bastard and got one of the mutant late model R33s with strange bits on it haha Nope, though I personally wouldn't go for the HTA2868 twins that are available - I doubt the combination would match up overly well to an RB... especially when squeezed into those little housings. Owen Developments sell them though, and someone installed a pair on his GTR but then had an engine failure which set him back something fierce so not sure if or when that will be back together. It seems folly to me to try and push past the "-5s" flow at this stage in those housings, I guess the closest to a setup like that which I would like to see would be more like upgrading low mount T517Zs to use the 68HTA wheels, probably less likely to surge and generally be a better match.

If you are looking at performance these days then turbo tech has moved along to a point you don't need to stress about an in between. Get an FP HTA GT3582R, will give SFA response (if any) to the GT3082R and make more power than the GT3582R