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31 Posts Member #: 4381 Member warwick |
22nd Sep, 2011 at 03:47:19pm
Long time lurker, first time poster etc. :)
Edited by maph2 on 22nd Sep, 2011. |
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1267 Posts Member #: 831 Post Whore Montreal, Canada |
22nd Sep, 2011 at 04:00:36pm
Are you sure you have a MegaSquirt and not a Megajolt? The MegaSquirt doesn't come configured for either TPS or MAP but always has both.
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 8604 Posts Member #: 573 Formerly Axel Podland |
22nd Sep, 2011 at 04:06:13pm
You seemed to have acknowledged the issues of siamese port injection but do not seem to have addressed them.
Edited by Paul S on 22nd Sep, 2011. Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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 6753 Posts Member #: 828 Post Whore uranus |
22nd Sep, 2011 at 04:19:53pm
id use the msqrt on a wet injector setup .,i have to go to some lengths to get a workable mixture on 5 12 15 and 20 psi ,a programmable setup would be a godsend .whether dry or wet. Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM |
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 (2)[/url] by [url=https://www.flickr.com/photos/150672766@N03/]Rod Sugden[/url], on Fli) 5988 Posts Member #: 2024 Formally Retired Rural Suffolk |
22nd Sep, 2011 at 04:32:46pm
Theoretically the wet manifold fuel injection (whichever ECU you use) can't be as good as a carb as the fuel is injected in pulses, not drawn in as a continuous stream.
Schrödinger's cat - so which one am I ??? |
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8604 Posts Member #: 573 Formerly Axel Podland |
22nd Sep, 2011 at 04:48:24pm
EDIT: read it wrong. Edited by Paul S on 22nd Sep, 2011. Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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1267 Posts Member #: 831 Post Whore Montreal, Canada |
22nd Sep, 2011 at 05:01:50pm
I think he's talking about a single TB with twin injectors. That would be a good wet manifold setup.
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8604 Posts Member #: 573 Formerly Axel Podland |
22nd Sep, 2011 at 05:15:25pm
Very PC Jean, but as yet I've not seen anyone post results of their fueling distribution on a wet manifold. Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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1267 Posts Member #: 831 Post Whore Montreal, Canada |
22nd Sep, 2011 at 05:36:55pm
On 22nd Sep, 2011 Paul S said:
Very PC Jean, but as yet I've not seen anyone post results of their fueling distribution on a wet manifold. It was not my intention to be PC but simply to say that a wet setup should be a viable alternative to a carb. However, I totally agree with you that no one has any data to prove or disprove this. And even if it is as good as a carb, it's still not very good in terms of fuel distribution as you've demonstrated. I think it's obvious that I'm in the same boat as you and a small minority in thinking that the real solution is to do the 'correct' thing, i.e., doing port injection with the siamese code or equivalent. What is interesting is that people (which seems to be the majority here) claim that doing this is too costly and too complex. And yet there is no questioning on the multiple 16-valve setups with all sorts of pricy EFI options (not to mention the cost and complexity of the head change itself) or the complexity of coming up with the 'perfect' needle profile in a carbed setup (which will never be perfect for all conditions and is much more complex than typing numbers on a PC and totally esoteric in my view). Anyway, that's getting a bit OT but not that much. Jean Edited by jbelanger on 22nd Sep, 2011. |
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8604 Posts Member #: 573 Formerly Axel Podland |
22nd Sep, 2011 at 05:45:32pm
Ahhh.... that's more like it :)
Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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31 Posts Member #: 4381 Member warwick |
22nd Sep, 2011 at 06:10:04pm
On 22nd Sep, 2011 Paul S said:
You seemed to have acknowledged the issues of siamese port injection but do not seem to have addressed them. . yes, you are right but i don't think i am trying to address them. i understand the problems but i realise that my skills, time and equipment available are probably far less than what is needed to set up the full fat siamesed port injection system that has been developed......unless i have missed something? i have a megasquirt unit that must be at least 4 years old. i paid for it to be build, set for TPS and i fitted to my redtop 16v engine for fuel and spark. not used it since. i figure seeing as i already have it, would it be better to use it - ie instead of a carb. folks are suggesting it should have MAP already, so it looks like i'll be using it for ignition at least. The manifold i have is for a single carb/TB set up as its aq cast inlet/exhaiust jobbie from an american market MG B - the exhaust manifold has a handy outlewt to bolt on a fabricated adaptor to take a turbo. if i did not already have a megasquirt ecu already, i would simply use a carb. i also still have source a turbo carb or convert a standard hif so you can see i'm at a decision point on what to do matt Edited by maph2 on 22nd Sep, 2011. |
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 665 Posts Member #: 9345 Post Whore Sheffield |
22nd Sep, 2011 at 06:24:15pm
I also think sequential port injection is best, as anyone who understands it would. My problem with it is complexity. It is not a beginners system and you can spend a lot of money on a dyno getting it right. The price of massive injectors doesn't help either, neither does the associated idle problems. Extra sensors (cam). Yes you can run multiple banks, but that just adds to the cost and complexity. In the end we already know the fuelling accuracy needed to make a "reliable" 200+bhp with a 5 port is easily achievable with a carb or wet manifold. Worst case is a couple of cylinders running a bit rich, which causes no problems.
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31 Posts Member #: 4381 Member warwick |
22nd Sep, 2011 at 06:33:38pm
yes, the last thing i want is to kick off a massive argument. I realise that the perfect way is to do sequential siamese injection.
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1267 Posts Member #: 831 Post Whore Montreal, Canada |
22nd Sep, 2011 at 06:53:43pm
On 22nd Sep, 2011 jamie@thefatgarage said:
I also think sequential port injection is best, as anyone who understands it would. My problem with it is complexity. It is not a beginners system and you can spend a lot of money on a dyno getting it right. The price of massive injectors doesn't help either, neither does the associated idle problems. Extra sensors (cam). Yes you can run multiple banks, but that just adds to the cost and complexity. In the end we already know the fuelling accuracy needed to make a "reliable" 200+bhp with a 5 port is easily achievable with a carb or wet manifold. Worst case is a couple of cylinders running a bit rich, which causes no problems. If you are running in some super regulated race series like F1 with things like available fuel (or weight of it) being a consideration then you would always use very accurate fuelling and run exactly at the desired point. Doing it in a mini with 150hp is an interesting hobby, environmentally friendly (not that I give a shit) and a great intellectual exercise. It also demonstrates great engineering skill and knowledge. It is not however, a requirement for a successful injected 5 port as is sometimes, probably unintentionally, hinted at in posts about EFI on here. It gets to the point with chasing AFR perfection, like the many cunning new ways to save a few grams from your car, it becomes a bit obsessive. This is in no way aimed at starting a massive argument or debate on the subject. It is aimed at encouraging more people to try injection who are a little scared of sequential on a siamese head if they have no previous experience. Simpler setups are easier, and cheaper. They are not perfect, but they are good enough to put your 5 port mini into the top few % in the country on performance. Anything that makes people more aware of EFI and helps them gain a little experience of it without jumping into one of the most complex ways of deploying it cannot be a bad thing and should be encouraged. Here endeth the rant. I agree with that last part but I think you miss the point at the beginning. I agree that getting more people to try EFI is a good thing which is why I was saying that the wet manifold setup discussed would be a viable alternative to a carb. However, when you say that good AFR distribution brings little you base this on incomplete data at best. Most, if not all, of the data we have on fuel distribution comes from the people running the siamese port injection on this forum. And it shows massive AFR differences in some circumstances. So under those circumstances, that means you either have some cylinders way too rich to produce best power or too lean which is also not the best for power or engine life. What is the AFR distribution of those running 200+bhp? I don't know and neither does anyone else. So could they make 5, 10, 30 more HP with the exact same boost and RPM? I don't know and neither does anyone else. But from data available, it is likely significant. My other point was that no one seems to be bothered by the fact that some resort to going to a 7-port or 16-valve setup which is way more complex and costly so why is it that doing the 5-port EFI thing seems to be considered futile and not the former? I know that at this point it's just theory but Paul has data showing the potential power increase you can get from simply playing with intake and exhaust geometry. Yet people will go with the freer breathing 7-8 port heads but completely neglect optimising the intake and exhaust. And no one questions it but dismiss the data as irrelevant or simply a nice theoretical exercise. Jean |
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1267 Posts Member #: 831 Post Whore Montreal, Canada |
22nd Sep, 2011 at 06:55:59pm
On 22nd Sep, 2011 maph2 said:
yes, the last thing i want is to kick off a massive argument. I realise that the perfect way is to do sequential siamese injection. But at least initially, i am limited to a single carb/single TB installation, therefore the options i have are either 1) carb 2) wet port single TB with twin injectors Any Megasquirt you have will be able to do the wet port setup. You should just make sure which version you have (MS1 or MS2 and V2.2 or V3.0 board) so that you can upgrade to the latest firmware and go from there. And all MS version have an on-board MAP sensor so that is not an issue. Jean |
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8604 Posts Member #: 573 Formerly Axel Podland |
22nd Sep, 2011 at 07:09:16pm
You need to go back about 5 years to the point where the TM forum started discussing the merits of wet manifold or port injection.
Edited by Paul S on 22nd Sep, 2011. Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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31 Posts Member #: 4381 Member warwick |
22nd Sep, 2011 at 07:52:15pm
OK, go carb
Edited by maph2 on 22nd Sep, 2011. |
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 9258 Posts Member #: 123 Post Whore Betwix Harrogate and York |
23rd Sep, 2011 at 08:10:05am
On 22nd Sep, 2011 jbelanger said:
My other point was that no one seems to be bothered by the fact that some resort to going to a 7-port or 16-valve setup which is way more complex and costly so why is it that doing the 5-port EFI thing seems to be considered futile and not the former? I know that at this point it's just theory but Paul has data showing the potential power increase you can get from simply playing with intake and exhaust geometry. Yet people will go with the freer breathing 7-8 port heads but completely neglect optimising the intake and exhaust. And no one questions it but dismiss the data as irrelevant or simply a nice theoretical exercise. Jean I don't necessarily agre with this. The advantage of 4 inlet ports is not simply to equal AFRs. and certinally going 7-port is less complicated than siamese injection. As for optimising inlet and exhausts, we all have to start somewhere. I'm happy that the 7-port theory has been shown to produce good power, now I can optimise; not even F1 manufacturers make a car right 1st time, quite the contary! And anyway, only one person on here has actually put any effort into optimising both inlet and exhausts, it just so happend he runs a 5-port. and even this has not yet been proved as actually being a worthwhile execise, and proably never will becase no back-to-back testing will ever be done. My 7-port was put on the same engine with the same turbo, the same manifolds etc, and made over 10% more power, pretty much as close to back-to-back as I could get. any changes I make now I can compare against a fixed point. one thing at at time allows a tru understanding of any gains (or losses) made. Fastest 998 mini in the world? 13.05 1/4 mile 106mph
On 2nd Jan, 2013 fastcarl said:
the design shows a distinct lack of imagination, talk about starting off with a clean sheet of paper, then not bothering to fucking draw on it,lol On 20th Apr, 2012 Paul S said:
I'm mainly concerned about swirl in the runners caused by the tangential entry. |
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 16540 Posts Member #: 4241 King Gaycharger, butt plug dealer, Sheldon Cooper and a BAC but generally a niceish fella if you dont mind a northerner Rotherham, South Yorkshire |
23rd Sep, 2011 at 08:20:49am
I agree with Jamie's comment about siamesed port injection being complicated.
On 11th Feb, 2015 robert said:
i tried putting soap on it , and heating it to brown , then slathered my new lube on it 
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 8297 Posts Member #: 408 Turbo Love Palace Fool Aylesbury |
23rd Sep, 2011 at 12:37:21pm
I think the main real reason most haven't gone down the 5 port EFI route is because at the moment it hasn't shown any real benefits over a carb for out and out power. https://www.facebook.com/pages/Fusion-Fabri..._homepage_panel
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1267 Posts Member #: 831 Post Whore Montreal, Canada |
23rd Sep, 2011 at 02:32:54pm
On 23rd Sep, 2011 wil_h said:
My 7-port was put on the same engine with the same turbo, the same manifolds etc, and made over 10% more power, pretty much as close to back-to-back as I could get. any changes I make now I can compare against a fixed point. one thing at at time allows a tru understanding of any gains (or losses) made. Ok, that's a good result and good objective data. But let me ask this: where is the additional power coming from? You either have more air going through the engine or you're making better use of it. If it's the latter (even partly), then it is likely due to a better AFR distribution which could be done on a 5-port head with the 'correct' approach. I'm not trying to put down anyone or any option. I just want to make people realise that there is a logic behind the siamese port injection idea and that it can be more straightforward and beneficial (in terms of cost and complexity) than people currently see. And remember that this is still the beginning so there's a lot of work yet to be done to make it easier but it is still not as complex as most think. And I agree that it's not as simple as typing numbers on a PC but when I see post about needle profiles I can't fathom that people find this more obvious. Or it's just that people are copying what others have done without understanding what's behind it. And again I don't want to put down anyone but that results in having to do a dyno run with the correct amount of choke applied to get a reasonable AFR. Jean |
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8604 Posts Member #: 573 Formerly Axel Podland |
23rd Sep, 2011 at 02:37:12pm
Jean, let's leave it. You're never going to win the arguement with people who feel they need to justify their own decisions by putting others down.
Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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1267 Posts Member #: 831 Post Whore Montreal, Canada |
23rd Sep, 2011 at 02:44:05pm
On 23rd Sep, 2011 matty said:
I think the main real reason most haven't gone down the 5 port EFI route is because at the moment it hasn't shown any real benefits over a carb for out and out power.  The problem with that is that unless someone builds a 350HP 5-port injected engine, there will always be someone saying that it could be done with a carb. And doing back-to-back tests to prove otherwise is almost impossible except for someone with unlimited funds who would want to prove the point. And it's a chicken and egg thing also. If you don't have more people who try it then it's difficult to develop and to prove. The main point of all my ranting is that I'd like people to not see this as a nice science experiment but as another alternative to the 7/8 port and 16 valve heads and even the traditional carb setup. And one that may be better on some aspects. Jean |
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1267 Posts Member #: 831 Post Whore Montreal, Canada |
23rd Sep, 2011 at 02:45:50pm
On 23rd Sep, 2011 Paul S said:
Jean, let's leave it. You're never going to win the arguement with people who feel they need to justify their own decisions by putting others down. Yeah, I'm done... for now. |
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Site Admin  15302 Posts Member #: 337 Fearless Tom Fenton, Avon Park 2007 & 2008 class D winner & TM legend. |
23rd Sep, 2011 at 02:48:45pm
I am watching with interest as I know for sure a lot of others are. Paul you are blazing a trail so keep at it, rightly or wrongly once you really have it cracked then I am sure more will follow your lead.
On 29th Nov, 2016 madmk1 said:
On 28th Nov, 2016 Rob Gavin said:
I refuse to pay for anything else Like fuel 😂😂 |
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