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 209 Posts Member #: 6451 Senior Member South East Northumberland |
31st Oct, 2020 at 06:09:31pm
Evening all,
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 869 Posts Member #: 2443 Post Whore Cheshire |
31st Oct, 2020 at 09:15:29pm
Hi I’m not sure how it’s costs in comparison to the other options but I would also consider an Emerald ECU, pretty straightforward to use and extremely well supported by emerald👍 |
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 2618 Posts Member #: 1246 Post Whore Lowestoft, Suffolk. |
31st Oct, 2020 at 09:38:18pm
I’ll second Emerald, it’s a superb system with great aftermarket support.
Edited by shane on 31st Oct, 2020. |
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209 Posts Member #: 6451 Senior Member South East Northumberland |
1st Nov, 2020 at 11:22:49am
Andy, Shane - do you have any experience of the Emerald ecu? Do you know if it uses the original MPi sensors or does it need additional items (uprated fuel regulator, trigger wheel etc)?
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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 |
1st Nov, 2020 at 12:01:13pm
On 31st Oct, 2020 Cooper1999 said:
A few questions I have if anyone can help me: Before the questions, bear in mind the MPI is a very different beast to the SPI. The SPI is a simple batch injection wet manifold setup that ignores the charge robbing issues that the "A" (and "B") series engines exhibit. To meet the emissions regulations of the last couple of years of production Rover had to come up with something that overcame charge robbing. To do so, they opted for port injection as close as possible to the valves they could and then they took a 4 channel MEMS, programmed its four outputs to match the 4 inlet vale opening timings - taking into account transit times, wall wetting and much more - the paralleled up pairs of outputs to feed the two single injectors. The inlet valve timings (open to close) are not symmetrical because of the inlet vale opening overlap so to make sure the fuel goes to the correct cylinder the injectors are very large compared to what you'd expect on a 1275 engine because they only get to inject when the inlet vales are open so need to run a very low duty cycle compared to an eight port engine. To try and keep them as small as possible what they then did with MEMS was programmed it so that at a certain RPM/load point, instead of four individual pulses corresponding to the inlet valve timings, they switched to a single "long" pulse that covered the combined openings of the inner and outer cylinder valves. Again, this has to be timed precisely to get the correct amounts of to offset the differing mass of air from charge robbing. If you ignore Rover's second tweak, then any programmable ECU that allows different injection timing tables for individual cylinders and allows four outputs to be paired as twos would achieve the same - so long as you have separate widebands on the inners and outers to be be able to tune the timings. An alternative is to ignore the fundamental single timed pulse per cylinder method and use the "long pulse" method. Again, any ECU where you can set the timing of two channels to specific values (which can be varied with RPM and load) would achieve the same. I must stress, the only reason I say all this is because the MPI setup is port injection. The majority of people take the much simpler approach of throttle body (sometimes called wet manifold or electronic carb) which is why the Specialist Components throttle body setup is so popular. I wasn't aware they now have something specific for the MPI port injection setup but if it mimics the specially programmed MEMS then I'm sure it can be made to work. But with any port injection, you will need two widebands or run the serious risk of all the fuel going into the inner cylinders. But, back to the questions On 31st Oct, 2020 Cooper1999 said:
Can the megasquirt work with the standard MPi set up? Yes, the MS2 can replicate all the features of the MEMS, the MS3 can use the timed long pulse method. On 31st Oct, 2020 Cooper1999 said:
Is anyone doing this and if so, what problems have you encountered? There are several of us doing port injection on the "A" series, so pretty similar to a standard MPI, but I don't know of anyone who's done it to a "standard" MPI. Graham T uses a lot of MPI parts but he's modified his MPI inlet manifold for additional (staged) injectors for higer power. On 31st Oct, 2020 Cooper1999 said:
- Does a trigger wheel need to be added to the MPi engine to use Megasquirt? How easy is this? If your chosen ECU recognises the totally weird tooth pattern of the reluctor ring on the back of the MPI flyheel, then no. Some aftermarket ones do because Lotus used the same pattern on their flywheels but it is most definately not commong (Megasquirt does although I'm not 100% sure anyone has used that bit of the code). Other wise just put a 36:1 trigger wheel on the crank pully like all the megajolt users do. Also note, any timed sequential injection ECU needs a cam trigger. The MPI does have one but it's a VR sensor (in the old fuel pump hole) and only works with an MPI specific cam (or a cam modified to match the MPI pickup). On 31st Oct, 2020 Cooper1999 said: Yes, high impedance and Paul or Graham may have their datasheet, I don't, I use low-z injectors.
Are the MPi injectors high impedance? Does anyone has a spec sheet or information on the standard injectors? On 31st Oct, 2020 Cooper1999 said:
Is the standard MPi coil pack up to the job? Not one I'm familiar with but I don't see why not (although there will be much better newer stuff available) On 31st Oct, 2020 Cooper1999 said:
Perhaps most importantly (for me), is the programmable element easy to navigate? With Megasquirt, I find the interface (TunerStudio) very easy to use. However, knowing what to adjust, when and why, is a completely different matter. You have to have two widebands to se what is going on with the inner and outer cylinders and you have to understand the effects changes will have and why. So, the overall answer is No.... But I like a challenge. On 31st Oct, 2020 Cooper1999 said:
I've spent the last hour or two using the search function, but haven't found a thread on using Megasquirt on a standard (components) MPi set up. If it's "standard" then why is MEMS not performing ? It should work fine with any MPI setup so long as the power hasn't been increased by much (I think it has a 10% margin). But beyond small increases it's just not programmable (in the normal sense) so little use on tuned engines. FINALLY, I must stress - because some will say I have over-complicated the issues - everything I have said is about port injection. If you want a simple life, go throttle body (wet manifold/electronic carb with batch injection four squirts per cycle) and it gets so much easier - hence the popularity of Specialist Components throttle body setup. Schrödinger's cat - so which one am I ??? |
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209 Posts Member #: 6451 Senior Member South East Northumberland |
1st Nov, 2020 at 12:11:49pm
Just had a look at the Emerald website.
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5988 Posts Member #: 2024 Formally Retired Rural Suffolk |
1st Nov, 2020 at 01:13:35pm
On 1st Nov, 2020 Cooper1999 said:
Reading this he comes to the same conclusion I think as SC, in so much as it isn't really possible to efficiently port inject the A-Series because of the siamese ports, better to run an 'electronic carb' wet manifold solution as efficiently as possible. The only thing I would disagree with is the "it isn't really possible to efficiently port inject the A-Series because of the siamese ports" Even the article you linked states that Rover achieved it. Rover did it to meet the then required emissions requirements, I guess that's my best definition of "efficiently"..... SC haven't been able to match the MEMS of its time (over twenty years later) hence why they push their throttle body solution. No, it's not easy to do port injection but perfectly possible as Rover showed (and a few of us on this forum)... But it's not for the faint hearted.... But if yours's is a genuine MPI of the age range it should be, how you intend passing a current MOT with the emissions you will get from a batch/wet manifold/electronic carb setup (ie, an SPI which would fail emissions on the age range of an MPI ?) Why not just sort out your MEMS which will pass the emissions standards ? Schrödinger's cat - so which one am I ??? |
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2618 Posts Member #: 1246 Post Whore Lowestoft, Suffolk. |
1st Nov, 2020 at 02:16:17pm
On 1st Nov, 2020 Cooper1999 said:
Andy, Shane - do you have any experience of the Emerald ecu? Do you know if it uses the original MPi sensors or does it need additional items (uprated fuel regulator, trigger wheel etc)? I'm going to have to learn this stuff but need it to be as (relatively) simple as possible - I really am starting from the electronic standing start! Thanks, |
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209 Posts Member #: 6451 Senior Member South East Northumberland |
1st Nov, 2020 at 05:34:23pm
Rod - some great info in your reply - Thank you.
Edited by Cooper1999 on 1st Nov, 2020. |
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5988 Posts Member #: 2024 Formally Retired Rural Suffolk |
1st Nov, 2020 at 06:31:05pm
On 1st Nov, 2020 shane said:
Yes I do, I run one on my K build. I use no MPI sensors, I used those that emerald sell which are off the shelf available items. Shane To be fair Shane, a K build can use any ECU you choose, pretty much. Even a Speeduino (about as cheap as you can get and, yes, I've built one just for fun and it works). Because what you get from a K build is a standard 8 port engine. The question was about a 5 port MPI using the basic MPI port injection system and mostly standard MPI parts and trying to replicate what the MEMS (programmed for the MPI) does. I'm sure Emerald is fine on any 8 port engine but I'd like to hear how it can deal with a five port siamese with only two direct siamesed port injectors. Note, again, I said port injection , not throttle body, which any ECU can deal with. Schrödinger's cat - so which one am I ??? |
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 8604 Posts Member #: 573 Formerly Axel Podland |
1st Nov, 2020 at 06:51:18pm
I have the Mpi manifold and sensors running on an MS3. As Rod says the MS can handle the flywheel and Cam sensor from the Mpi. You should be able to run the Mpi coil in wasted spark mode off the Ms.
Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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8604 Posts Member #: 573 Formerly Axel Podland |
1st Nov, 2020 at 06:51:23pm
I have the Mpi manifold and sensors running on an MS3. As Rod says the MS can handle the flywheel and Cam sensor from the Mpi. You should be able to run the Mpi coil in wasted spark mode off the Ms.
Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
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8604 Posts Member #: 573 Formerly Axel Podland |
1st Nov, 2020 at 06:54:46pm
Some useful info:
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 |
1st Nov, 2020 at 09:00:20pm
To use port injection on a 5-port engine (MPi or otherwise), you need to be willing to learn and understand why injection timing is essential and how it works.
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2618 Posts Member #: 1246 Post Whore Lowestoft, Suffolk. |
1st Nov, 2020 at 09:42:23pm
On 1st Nov, 2020 Rod S said:
On 1st Nov, 2020 shane said:
Yes I do, I run one on my K build. I use no MPI sensors, I used those that emerald sell which are off the shelf available items. Shane To be fair Shane, a K build can use any ECU you choose, pretty much. Even a Speeduino (about as cheap as you can get and, yes, I've built one just for fun and it works). Because what you get from a K build is a standard 8 port engine. The question was about a 5 port MPI using the basic MPI port injection system and mostly standard MPI parts and trying to replicate what the MEMS (programmed for the MPI) does. I'm sure Emerald is fine on any 8 port engine but I'd like to hear how it can deal with a five port siamese with only two direct siamesed port injectors. Note, again, I said port injection , not throttle body, which any ECU can deal with. |
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5988 Posts Member #: 2024 Formally Retired Rural Suffolk |
2nd Nov, 2020 at 11:14:26am
No offence intended Shane, I just wanted to ensure anyone who might read this in the future (from searching the subject) that the MPI injection (or any other port injection) on an "A" series is quite different to port (or throttle body) injection on 8 port engines.
Schrödinger's cat - so which one am I ??? |
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2618 Posts Member #: 1246 Post Whore Lowestoft, Suffolk. |
2nd Nov, 2020 at 01:32:01pm
On 2nd Nov, 2020 Rod S said:
No offence intended Shane, I just wanted to ensure anyone who might read this in the future (from searching the subject) that the MPI injection (or any other port injection) on an "A" series is quite different to port (or throttle body) injection on 8 port engines. Rod. |
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869 Posts Member #: 2443 Post Whore Cheshire |
3rd Nov, 2020 at 08:47:56pm
Hi Guys,
Edited by Andy500 on 4th Nov, 2020. |
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5988 Posts Member #: 2024 Formally Retired Rural Suffolk |
4th Nov, 2020 at 11:15:24am
I've got to love this bit
On 3rd Nov, 2020 Andy500 said:
Admittedly it was a bugger come MOT time but it could be done with a second map. I did get dragged into one of Anna's (wifey's) friends Lotus with an early Emerald setup about 15 years ago (so, before I learnt Megasquirt/TunerStudio) and his comment was that the MOT map was fine but slow and the performance map was crap and an MOT fail. It was just the "MOT map" phrase that was just so... well you know what I mean. I found his problem was a bad joint on the exhaust downpipe - his custom manifold just had an open sliding joint rather than a sealed bellows so was leaking in masses of air before the wideband sensor. I'd just never heard the "MOT map" phrase before.... But the Emerald software interface was fine to me at the time and I'm sure it's probably a lot better now. I just don't think it would cope with a five port, but those of you on eight ports it's probably one of the best "off the shelf" solutions if you don't want too much DIY. Schrödinger's cat - so which one am I ??? |
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209 Posts Member #: 6451 Senior Member South East Northumberland |
8th Nov, 2020 at 07:41:45pm
Okay - so I'm talking to someone who can build up the Megasquirt for me (one of my worries) and a new engine loom, who advises possibly using a VW coil pack (they have they're own 'drivers', and are relatively cheap and easily available I'm told), a wideband sensor and a 36-1 trigger wheel if possible (I read the comment in an earlier reply that the MS2 can utilise the standard items).
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5988 Posts Member #: 2024 Formally Retired Rural Suffolk |
9th Nov, 2020 at 01:02:52pm
First, let me say again, if you are going to do any form of port injection, MPI based or otherwise, you need TWO widebands, one for the inner cylinders and one for the outer.
Edited by Rod S on 10th Nov, 2020. Schrödinger's cat - so which one am I ??? |
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240 Posts Member #: 11017 Senior Member Shropshire |
9th Nov, 2020 at 10:48:44pm
Not sure why you're so hell bent to use the MPI manifold when you're going to struggle unless you have taken heed of what Rod has written. I ditched it and went SC wet TB and getting good results on an MPi engine with a turbo 👍🏽 |
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5988 Posts Member #: 2024 Formally Retired Rural Suffolk |
10th Nov, 2020 at 06:29:48am
As Steve says, unless you fully understand (or want to learn) the complexities of port injection just use a well proven TB/wet manifold/electronic carb setup and set it as lean as can get away with to pass the emissions test on your IVA (or find a way of avoiding the IVA...). Schrödinger's cat - so which one am I ??? |
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240 Posts Member #: 11017 Senior Member Shropshire |
10th Nov, 2020 at 02:27:00pm
Mine passes the MOT emissions for a 2000 plate car perfectly each year |
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209 Posts Member #: 6451 Senior Member South East Northumberland |
14th Nov, 2020 at 06:36:21pm
Some great info in the link. I've much to learn I think.
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