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Lithium

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Everything posted by Lithium

  1. Hahah that looks pretty familiar. I do very similar, before matchbot I just had an array of spreadsheets I used but MB does help/make me a little lazier than I used to be but handy because I don't have as much spare time as I used to so anything which makes it easier ftw. It's kinda handy that it dumps all the working out so you can effectively map turbine flow maps from other manufacturers out by adjusting the turbine expansion ratio and monitoring the turbine corrected flow, just making sure that you take into account the correction factors used for each. He's effectively talking about how much leverage is applied to each side of the WG, you need an ECU which can control two separate boost control solenoids independantly. One is for controlling how much "opening force" is applied to the gate, and the other for how much "closing force" is applied. If you can apply the full boost pressure to holding the gate closed, and non of the boost pressure to opening it - then you in theory can go way past the sprung pressure... but being able to fine tune both sides means you should be able to limit erratic behaviour as you reach boost targets. The closest to this you will achieve with the typical "single direction" boost control setups is using a 4-port boost control solenoid - the example you linked is slightly simpler again, "single direction" but with a 3 port solenoid which means you never have the option of applying full pressure exclusively to either side of the gate.
  2. Gotcha. This is on the OS 3.15? It hasn't got a big tube manifold or something, has it? And with the turbine rpm pick up tests are you doing it on the road (ie, where there is gearing and weight of a vehicle involved) or is it steady state against a dyno? Depending on that lot, what you say paints the picture that could be interpreted to say that inertia isn't your primary problem and that it's got a lot to do with how your exhaust energy etc is being harnessed. 13Bs I guess aren't exactly lacking in creating exhaust energy I guess. That short-runner/high exhaust energy thing is why I kinda view twins as a no brainer on Vs and singles, and it'd be nice on the straight 6 if it weren't for the fact that everything was so cluttered that the benefits are arguably some what scuttled by the fact that pushing exhaust gas into the turbine isn't the only factor involved in making an engine perform What kind of spec is the best power vs drivability RB-based setup you're encountered so far?
  3. There is actually some info on twins, a member has been running twin EFR6258s on a "good" RB28DETT setup in a track car for years and also tried the EFR7163s briefly. Here is the dyno results with the EFR6258s: And his comments on the EFR7163s:
  4. What size engine and what kind of setup are you talking about re: this 3500rpm test btw? 3.2 with an EFR9180? I doubt Borg Warner are going to do a big enough EFR to justify an upgrade from a 9180, though I don't know for sure. How much of a rush are you guys in to change? Fairly safe to say that there is very likely to be changes in the turbo market before the year ends...
  5. The only people I know who may have a chance of providing this kind of data is @bri73y or @Full-Race Geoff
  6. That's pretty interesting, and pretty impressive really. I would not be in the slightest surprised if the rpm delta improves going to twin EFR7163s, to compare this kind of acceleration it'd be more accurate (though not perfect) to compare tip speed. 60,000rpm/s rate of change = 286m/s/s acceleration, which you need around 77,000rpm/s to match with the EFR7163s. I've never seen any inertia data and I've seen people make big assumptions one way or another, I'm not going to do the topic the injustice of me speculating wildly on that like it could be easy to fall in to. If we're going to end up with some real world data then we may as well wait for that and see where everything sits - hopefully there aren't other variables at play, like manifolding as close to equivalent and engine spec exactly the same otherwise it'll lose the meaning a bit. There really are two different discussions happening here though, from what I can tell - and it's probably worth identifying it so we're not all talking cross purposes. 1) Are the EFR7163s a better match for what RICE RACING is trying to do? By the sound of it, quite likely. 2) Are they going to be more responsive and/or drivable than a single EFR9180 with all other things equal - I'm not so sure, but very interesting to see. If they manage to be then that is a HUGE thing.
  7. Sounds good! It'd be awesome if you do get some results, both dyno and real world. There is no magic or mystery in the idea that if you can make decent use of 25% more flow that you will go faster, whether you use a single or two turbos to get either result. One of the fastest GTRs in the world around a track will be going from a 9180 to 120lb/min of high mount twins so look forward to seeing how that comes together too
  8. Yeah, pretty sure we've all discussed this before - though it doesn't really fix the room for dump pipes, intake piping etc however it seems some people have got reasonable setups in there which may allow the turbos all the breathing they need. The other trick with dual plenums (or twin turbos in general) is if you really are doing things properly and carefully, you probably should have separate load calculations done for each set of cylinders with it's own turbo. @AdapTronic 's Modular ECU supports tuning separate banks where dual plenums are involved, dealing with the fact that even with a seemingly symmetrical mechanical setup will result in the two banks having different flow and different boost characteristics... which is potentially being a significantly bigger trap (which is more often overlooked) for making a tune which doesn't suit the engine perfectly than the typical concern people have tuning RBs where they give a little extra fuel to certain cylinders. Yeah absolutely, I wasn't saying that 3.2litre at 11,000rpm is the same as a 2.2 at 11,000rpm - though perhaps I got a bit hung up on the idea that 6500rpm is a lot of rpm when it's about the equivalent to a 3.2 at 4500rpm. The concept I was getting at still applies, though - if you have a setup where the 9180 is rolling over at 7500rpm, a pair of 7163s might give you a fairly decent amount more usable rpm with less of a cost at low rpm. So laggier, but the amount of torque spread at the higher end more than makes it up - you just shift you rpm range to the right a bit. No issue on the inlet side in which setup? I believe there is an issue with the inlets on low mount twins on an RB, but definitely not with a single on a V6 - totally agreed with the exhaust being the big issue with a V6 single turbo setup, different problems but similar end result where a turbo doesn't perform as well as it could with a different environment. Yeah gotta say, a serious full house 3.2litre with a pair of 7163s would be very interesting to see - the potential is strong if they can be made to work in unison with each other than the engine at the higher end of their power potential. The way I view it however is that it's the equivalent to going to a bigger turbo setup that suits the higher needs better, a bit later in the rpm but potentially has a slightly better cost vs reward... which is often the case when you end up with a parts match that better suits the target. It's not so simple as "one size fits all".
  9. Sorry I should clarify here, I am all for twin turbos on V6s - which is is a completely different engine bay configuration to a straight 6. With a straight 6, twins have to be kept on one side of the engine so they end up tripping over each other's plumbing as well as other things that need to occupy engine bay space - there seems to almost always end up being compromises made which could negatively affect the performance of the turbochargers... which may otherwise be capable of better performance. With a V, a single turbo needs to be fed by exhaust gases from sets of exhaust ports facing in opposite directions on the opposite sides of a V - ending up with different, but still relevant compromises made in exhaust manifold and piping design over what would be ideal. It's easier to make an optimal single turbo setup on a straight 6, and it's easier to make an optimal twin turbo setup on a V6 - the results usually seem to reflect that in practice, from what I've seen so far. That aside, Indy cars spin to >11,000rpm so I'm not sure I'd refer to them and EFR7163s as a "low rpm" setup. Spinning a highly efficient 2.2litre engine to >11,000 sounds like a thing which could easily result in the EFR9180 choking the engine a bit, while I don't know at all for sure - it wouldn't surprise me too much if the gains, even if not power gains, are in adding width to the power band by holding power better at the higher rpm... not picking up more power at the basement, but "helping" at the lower end by allowing gearing/shift points which are better suited to the huge rpm they've built those motors to live in. If you have a comparison between an equivalent and a single "true split pulse" setup going through gears it would be really really interesting! Definitely all keen for data which can help back up, or justify re-assessing my opinions. It's all part of the mission to work out how to make things go better
  10. Is the boost control issue sorted? Still looks a little on the lazier size
  11. Interesting, more power seems like a no brainer - but you expect some improvement in response as well with the twins? I am assuming you're talking at least EFR6758 size? Please share results if you do it, if there is any "cake and eat it too" solution over the EFR9180 on an RB I'd be quite keen to see it - but I definitely don't have anywhere near the confidence that the twin kits will deliver to suggest someone change... but in data we trust.
  12. Hi, sir... I found this thread doing a search and it is nice I was asked (as often happens) to try and match a nice turbo for a mates RB25 track car with some very specific requirements, ie ball bearing, within a limited budget, T3 open flanged and able to make around 450kw @ hubs on E85 on a Dynapack dyno. I did some crawling around and decided to pay more attention to the GTW3476R than I had really given it previously (Garrett took AGES to release flow data for them) and I was actually pretty blown away by the match that they give, at least on paper. They actually look like an awesome combination from that point of view. How have you found you found yours so far? Real world response etc fairly acceptable for the power you are making? Was that power figure "all in"? Cheers
  13. "Since this first step is all about low-end torque and throttle response, I thought the HKS route would be the best option." Riiiiiightttt
  14. Yeah flat shift and other antilag strategies are all awesome as well, and given @Piggaz has a sequential with flatshift etc also - I suspect it's not going to be the worst. I guess it's a shame he doesn't have transient (like off/on versus gear shifting) data from prior to the 1.05 as that's probably what will suffer the most on with the change to that 1.45 housing.
  15. I think most people seriously interested in EFR turbos are interested in them because they don't miss that basic point
  16. PS Mr @RICE RACING, if it's not inappropriate to ask - how does the EFR9180 hold on up high on the 3.2? I have a mate having issues with his 9180 RB32 build, it's falling on it's face at 6000rpm - like power is rolling over hard. He changed from 1.05 to 1.45 and it's made no difference at high rpm, and it happens at all boost levels. I'm not currently at all convinced it's the turbo though some sound like they're suggesting it is. It is also struggling to make the power it should be - actually barely making any more than a good EFR8374 setup would, imho.
  17. That makes for some good reading as is, thanks for sharing - lines up relatively well with how I kind of picture things. Obviously a 1:1 pressure ratio across the engine is ideal from the stand point of something that doesn't have to deal with transient conditions (drags, steady state etc) but I definitely feel that letting a bit of drift upwards in EMAP to ensure response etc is not the worst thing in the world. Hell, it seems only to be a semi recent thing where people start shunning anything over 1:1 for road/track cars when previously it was usually a target for drag cars. These days it gets more plausible because turbos etc are so much more efficient that you can float around 1:1 and still have fairly decent response. Obviously there is no one size fits all as it depends on temperatures etc etc etc, but I think a lot of people would shxt if they knew what most factory turbo cars, rally cars, and most serious race cars have run in terms of IMAP vs EMAP. In @Piggaz case however, it sounds like the bigger housing is not likely to really cost anything which is going to compromise his driving experience much - the 1.05 EFR8374 sounds like a response beast, and having surge issues down low is a nightmare I've had to deal with in the past and I can associate with wanting to try stuff to get rid of it... especially if part of your buzz is trying new things and learning from it. I'd probably have just gone a 1.05 EFR9180 to reslve it, but there is no secret I have a raging one for those turbos haha.
  18. Haha yes, I'm very very interested in this as well. The data geek in my is a little sad that there wasn't at attempt to run it up to max rpm with the 1.05 to get a flat out comparison of EMAP, IMAP and power along with spool between the 1.05 and 1.45 but I understand the position of being a tuner and also owner of a car and having your comfort levels etc. While 360kpa:260kpa EMAP:IMAP (1.38:1 EMAP:IMAP) is starting to build up a bit I didn't personally think it was over the top, especially when so close to the suggested max compressor speed - but who am I to question when someone is willing to try the big housing out on an engine which is as likely as any to justify the large one? ESPECIALLY with all the data @Piggaz has set up to be able to record. How the new housing affects spool, cylinder filling, surge, compressor speed, power etc etc is all very relevant to my interests. So much science! Looking forward to seeing how this comes out
  19. I've had a few false starts trying to add 2c to this topic but keep ending up tied up with other things, but I thought I'd at least throw this out there: It's one of the best performing RB setups I've seen, I love it.
  20. Will hold off the (like) until you post a dyno plot (y)
  21. Yeah good on them for being the guinea cops at that kind of expense, that is a LOT of unproven turbo to jump into using on a 2.8litre turn-corners-car. Will be very interesting to see how they perform in the real world, they do definitely seem to be not shy of pumping some air!
  22. Yep, from my experience with an 8374 on even an RB26 I can't see why you would go smaller... not remotely comparable to the lag of -5s haha
  23. They are out, just doesn't seem like a lot of people have tried them - or at least boasted about their results so far. It's probably too early to draw any conclusions one way or another from what little info is out there, it feels like there is potential there. The odds are there are a lot of people like you, who are interested and thinking about it but want someone else to try it first - which is very reasonable... but also means there is probably not much point holding your breath. The "next size up" G-series are likely to be more interesting to everyone, it was an interesting choice going for the baby size first.
  24. I wouldn't hold my breath, I certainly haven't heard any hints of anyone doing such a build and given they won't realistically be bolt on options I'd say most would go for known and easier/cheaper to fit combinations. There are VERY few dyno results out the for the G25s, and so far I've seen nothing worth really writing home about. The most indicative of any potential I've seen is an EJ25 powered Subaru with a .72a/r G25-660 on it putting down a bit over 500whp (~370wkw) on a Mainline roller dyno at 26psi with full boost coming in in the mid/low 4000rpm range. It's decent, but nothing to put the EFRs on notice.
  25. Nice - any more specifics? Been quite curious about the SX-E turbos and a few RBs seem to have them but no dyno sheets or hardly even any numbers, yours included now haha
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