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Lithium

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Lithium last won the day on February 20 2018

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About Lithium

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    Rank: RB30E

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    lith@clear.net.nz
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    Wellington, NZ

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    2007 Mazdaspeed Axela
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    Mr Lith

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  1. Nice work! Hope you are going to have a better filter than that on it, though haha. So it's still a reasonable way away from dyno time then?
  2. Turbine inlet pressure. Speaking overly simply, the wastegate works on the balance of boost pressure, turbine inlet pressure, and spring pressure applied to the valve. The spring pressure offsets that to start with, but you can manipulate pressure on top or bottom of the wastegate using various methods to get more and more control of the balance across the valve.
  3. As much I was half just giving a cheeky wind up, I did actually underestimate how configurable the Syvecs is. My limited experience with it so far has been a general look over the software and specs for a project I will be involved with to investigate whether Syvecs was going to be appropriate overall for the project. It was the front-runner by default as it is they provided the only real stand-alone option we are aware of which we could get capable of controlling BMW DCT ... but was still worth doing due diligence. After this discussion I went a lot deeper into the boost control (and a few other) bits. As you say, in terms of the "motorsport" related features it is really quite packed right from the outset - looking forward to having a play with one when the aforementioned project reaches that stage. Tbh I think a LOT of us want to see an EFR8474 on a strong RB setup and are looking for a guinea pig. What answer are you expecting, here? No point if you are going to stay with injectors which can't keep up with your existing fuel setup however, so depends on whether you are willing to bring the rest of the car up to spec to handle what the 8474 is likely to be able to offer. If you do, please don't use a .92a/r hotside on it.
  4. I wouldn't have really thought targetting a max compressor tip speed would be an ideal boost control strategy, or do you mean have a compressor tip speed as a somewhere between a limit and a target, so say (to be overly simplified about it) you set a 30psi target boost pressure from 3500 to 8000rpm, with an additional 127,000rpm max turbine speed so it maintains 30psi unless turbine speed hits the limit, then bleed it back? It does sound like it would be fun to experiment with, however. Motec (and some other ECU manufacturers) also have log analysis software which would be able to do functions like you describe there in regards to the correlating shaft speed to wastegate position if you have the sensors attached. At first thought I'd be surprised if there is a constant correlation between those two but the data would be very interesting to look over. As you say, "as delivered" most started ECU packages (Syvecs included, I thought?) don't really use the shaft speed for targetting - so much as for setting a limit before stopping the party if things go past currently defined limit, as opposed to a closed loop control trying to target the shaft speed. Does sound like an interesting thing to have a play with in M1 Build if I end up with the time and opportunity to do some testing with that kind of thing, though.
  5. Seen nothing at all Still a bit dark that the G30 & G35 have seemingly been considered the least relevant for release when they are the most interesting, at least to me.
  6. Do you have a wideband on it or anything? That FCon must be harder and harder to find people to tune, are you likely to stay with it?
  7. I just assumed they used a pic of the old EFR9180 they ran, but perhaps it was a prototype one they ran which didn't have the black compressor. Either way they've had an EFR9280 on the car since last year and the results they were talking about were definitely the black series.
  8. Thought I would just throw this in here...
  9. Looking like it's coming together nicely, and yeah the EFRs aren't the prettiest - a shame they seem to have done an aesthetically nicer job with the SX-E range.. though that doesn't make things go any better. Also I can't remember if it was discussed earlier, what fuel pumps are you using? Your injectors really should be capable of supporting a fair bit of power.
  10. Yeah not too surprised that the EFR9180 was out, I would 100% expect the 6870 to outflow it - and by a bit of a margin. The boost threshold however is a definite surprise. Interesting how some results can vary! Hard to know what to make of it.
  11. First time I've ever seen a 6870 come on earlier than a 9180, what other changes were made?
  12. Lol Jesus. I should have proof read, but yes I did and I'm sure people get it but thanks haha
  13. OK, I've just read through a bunch of comments which flowed on from here which I agree and disagree with to a varying degree but as usual there is a little mis- or half-information that I don't feel like anyone considering them are getting enough to make an reasonably informed decision and for a change I actually have time on my side today, so I'll answer with more than just the easy "I agree with Micko". Like always, this is just my view point - I don't profess to know f**k all and know there are people who do or will imply that I don't, so take that as you will but I think it's worth at least using things people say to base your own research before deciding whether it's bullshit or not. ESPECIALLY when it comes to injectors, as they literally supply the fuel for your combustion - debating turbos is one thing, making a decision which could cost you a very expensive engine is a different thing altogether. There are a lot of different things in this topic so I'll try and put some light on the things that usually are or should be on peoples minds about them. This whole post is SPECIFICALLY about "Bosch 2200cc" / ID2000 injectors. So I'll focus on these things for the two major areas people talk about these, firstly the relatively academic/harmless area people debate about these injectors and then will ramble about the bigger issues. ID2000s vs Bosch 2200cc injectors Straight up, they are the same hardware. Injector Dynamics themselves do not hide that fact, and put a lot of work into matching them so strictly speaking they are "better" than just going with generic Bosch 2200cc brands. Check out the link here: http://injectordynamics.com/articles/does-dynamic-matching-really-matter/ There is likely to be less pain tuning ID2000s than generic Bosch 2200cc injectors, but that is missing the point... there is likely to be problems at some point, the question isn't so much if - but how bad, exactly how bad will be under a different heading. So yeah, that Injector dynamics page IS accurate but it's kind of glossed over things and made out like their injectors will fix drivability issues and the flow as tested has a very small range of error at higher pulse widths - which is kinda true, however they have only plotted down to 2ms total pulse width. Below is a scatter plot showing rpm vs actual pulse width from a car using these injectors on BP98, I've set any load points plotted which are under atmospheric to show as green - as it comes into the transition to boost area it will go through from orange to red. Notice how much of the driving around this car does exists BELOW the 2ms range plotted by ID in their graph? (note, the flat line around 1ms is due to the affect of a combination of short pulse adder and dead time settings). These injectors have quite short dead times relative to the flow that they have, and as the linked article suggests - not every injector is made equal. A significant thing about this is that the dead times between any two injectors can vary by a small amount, if that amount is still significant compared to the average (or the configured....) dead time and you have injectors which flow a heap of fuel for a small amount of open time then the amount of variation in flow between each injector can be very significant. Because of this fact, as the pulse width gets shorter the potential for deviation in relative flow between each injector increases significantly - the unmatched ones going exponentially different by 2ms, and the ID2000s even are starting to show the trend. It'd be very interesting to see what would have happened if that chart was shown down to 2ms, it is a shame that they didn't show results closer to the 1ms mark - my logging essentially shows that basically all typical driving on pump gas will be done below the pulsewidths that they will be operating with. Those variations in flow DO matter if you give a shit about drivability, it is the kind of thing that causes shitty starts, hesitations at transient throttle, less than ideal idle quality and such forth. They can be glossed over by tuning them to run richer mixtures, but still bear in mind that this is a band aid - and one that's not lovely. The variation in flow between cylinders in different situations is still going to be there, it's just been masked. This may not bother everyone, and will obviously be less of an issue with E85 where you immediately add >30% to your pulse widths for a given amount of airflow - but then this is the most trivial concern with using these injectors, so I'll move on to the bigger concerns. These injectors are CNG injectors The implications of this seem to be mostly poorly understood or communicated. I'm not going to profess to know heaps about it to be honest, I am not an injector engineer and don't know a lot about how they work *but* this whole tuning lark is like that. Everyone knows some of the picture, doubt the f**k out of anyone who is 100% confident on everything they are talking about. I do feel there are some basic points which aren't questioned or discussed and they are pretty meaningful here. Hear me out... When the "CNG injectors" thing comes up, it is usually when discussing E85 use. That is kind of true, they are not designed to use E85. People talk about them being "OK" if they use stainless internals.... welllll..... that is only part of the picture and that certainly doesn't make them safer. It is true, they aren't designed to use on E85 - but that's more to do with the fact that E85 is a fluid and they are NOT DESIGNED TO WORK WITH FLUIDS. Any fluid. Here is something from the horses mouth: So what does this mean? I can't say exactly what the behaviour inside is, how long it takes, how likely it is to happen etc but I have had the misfortune of having to deal with cars running these injectors and I am finicky enough to analyse the shit out of everything and identify things that are not working the way they should be and try and work out what or how the problem is occuring. A lot of people don't run into issues, from what I've seen they are either lucky or just are not paying enough attention to realise what is going on. Likely a bit of both. What I do know is that these injectors can change how much they flow over time when used with fluids. That can be a mixture between immediate, and longer term. There are PLENTY of cases where people have run into tuning issues or even engine failures and returned them to a supplier who has tested them and found that where they previously were ~2200cc/min at 3bar they are now <2000cc min with possibly a greater margain of error between the injectors. That has been previously deemed not enough to cause the issues seen, they've been given some love and back to their previous flow level and everyone has been happy. At least temporarily. This is where things get scarier though, their flow behaviour can change on a much more minor time scale. Like in the period of half an hour, with no tune changes, the same IAT/ECT and basically all typical variables within a range where you would expect a minimum variance in flow. I'm talking well over 10% in flow, with a significant error between each injector. It seems like it can be associated with fuel temperature, and likely is - however this is not a consistent error... corrected volumetric to mass flow calculations which take into account fuel temperature will not fix this, as it isn't about the density of the fuel changing. It's about how the actual injectors are delivering the fuel, essentially delivering an inconsistent fuel volume for the same pulse width at different times. It is not a huge leap to make to assume that this can be attributed to the whole "swelling behaviour of elastomer seal in liquid media" thing - which is not a one way street with this kind of material. Basically they can swell and contract depending on temperature and exposure to fluids, the elastomer seal is designed to stop a gas from seeping past the injector when the injector is not meant to be allowing fuel through - and the upshot of this is there is a thing which is not intended to be used in a way which can cause it to swell and contract means that the rate which it does it is not consistent in any way. They are meant to be dry. The upshot of this is that when you hear about these cases where a car has had a lean out on these injectors and hurt an engine, the injectors have blamed for being "blocked" due to E85.... that absolutely can be the case, but every now and then you hear about the injectors being tested and they've turned out fine and things get messier - this is where the horror starts. You don't need E85 to cause this issue. You don't need foreign contaminants. The injectors can return back (more or less) to the flow behaviour they had before and not give any hint that one or many of the injectors at one point during operation may have dropped to <2000cc/min of flow on a car tuned assuming 2200cc/min flow potential. A cylinder which was happy running 30psi on E85 at 11.5:1 (petrol scale because most people seem to talk in that even on E85) may not be so stoked with running 13.0:1. The same car can richen up or lean out further depending on the mood of the injectors, and there is no way for you to know how when, if or how bad the problem will happen but based on what I've seen it would be foolish to use these injectors and not expect it. There are other things which E85 and methanol, or even MTBE (which is used in plenty of other fuels and have similar properties to E85 which can negatively affect fuel systems ) which can cause issues - that is a whole different topic which does cross over into this one, but is actually less scary that what I've actually seen. I've been unfortunate enough to see the shenanigans these injectors can offer, owners of cars I've been behind the laptop where these injectors have been used have been fortunate enough to have someone that picky that we've noticed things before they became a problem, and as such I'm fortunate enough to not have melted an engine when using these as I've pulled the plug and insisted they get changed before something goes wrong. I know others who haven't been so lucky. So yeah, this is my opinion and based arguably on anecdotal evidence - but if anyone wanted a more substantial explanation of why not to use these injectors than "throw them in the bin" or "they're shit", I at least feel like I've done my part to ensure there is something to chew on... take it as you will. PS. Just don't. PPS. Sorry for the overly long rant, I look forward to the TL;DRs and hiding under my rock again until next time I get bored and put my neck out with an opinion.
  14. A chap I know has tried all of them, actually just tuned a car running a 6466 with a 1.00 and is looking at going 1.15 - said the difference in flow between .84 and 1.00 is significant in itself, picked up a LOT of power "pound for pound" when going north of 20psi and only lost about 200rpm on a stock stroke RB26. It's holding peak power at around 8000rpm with the RB26 at ~650awkw on a Dynapack on E85. He is pretty certain the 1.00 is a better balance of response versus power than the .84 even on an RB26.
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