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 774 Posts Member #: 6724 Post Whore Wootton Bassett |
12th Sep, 2023 at 10:44:40am
If you were to look back through the threads you would see this project has been in the pipeline for a while.
Edited by dan187 on 12th Sep, 2023. |
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 969 Posts Member #: 3228 Post Whore North of the Netherlands |
12th Sep, 2023 at 12:25:37pm
Congratulations!
Dazed and Confused.... |
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
12th Sep, 2023 at 04:59:06pm
images fixed Edited by dan187 on 12th Sep, 2023. |
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247 Posts Member #: 11017 Senior Member Shropshire |
12th Sep, 2023 at 07:02:47pm
Saw this on FB, love the set up! |
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 4620 Posts Member #: 20 My sister is so fit I won't show anyone her picture Lake District |
12th Sep, 2023 at 07:12:12pm
Nice!
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
12th Sep, 2023 at 07:34:12pm
Cheers chaps.
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
12th Sep, 2023 at 07:47:15pm
I believe this image is from someone on here. The question to confirm is where in the cycle should no.1 intake valve motion be located? Between roughly 30 BTDC and -200 BTDC? (thus making the green intake on the image suited to cylinder 4?)
Edited by dan187 on 12th Sep, 2023. |
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247 Posts Member #: 11017 Senior Member Shropshire |
12th Sep, 2023 at 08:09:00pm
Not sure if this is of any use
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
12th Sep, 2023 at 08:39:37pm
On 12th Sep, 2023 Steve220 said:
Not sure if this is of any use https://rovermems.com/discussion/mpi-injection-timing.html https://www.starchak.ca/efi/siamese.htm Thanks Steve, I've been referencing those. But the starchak timing table is the bit that confuses me. Perhaps my cam is 360° out compared to Rover? When they use 560° I've dialled in ~100° to get the fuelling to work. Edited by dan187 on 12th Sep, 2023. |
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
12th Sep, 2023 at 08:40:40pm
What fuel pressure regulators are EFi people using with their turbo? I've had a thought that maybe the issue is that the rate isn't rising with boost (hence the difficulty tuning)? |
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
12th Sep, 2023 at 08:43:41pm
Revision A of the inlet to help show the injector bosses and angles on the injectors (which are the same for the final embodiment).
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247 Posts Member #: 11017 Senior Member Shropshire |
12th Sep, 2023 at 08:49:20pm
I had a weber 3bar efi one. Now have an adjust AEM FPR. |
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
12th Sep, 2023 at 09:13:16pm
Thanks Steve.
Edited by dan187 on 12th Sep, 2023. |
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 606 Posts Member #: 1106 Post Whore Hungerford, Berks |
13th Sep, 2023 at 06:47:41am
Looking Good Dan.
’77 Clubman build thread
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
13th Sep, 2023 at 07:07:41am
Thanks Graham,
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
13th Sep, 2023 at 07:11:20am
Looking at the SW5 cam photos the cam lobe is roughly aligned with no.2 intake valve full lift (which is 180 crank deg later than Graham's plot).
Edited by dan187 on 13th Sep, 2023. |
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
13th Sep, 2023 at 09:04:47am
With the confidence that my injector timing is in the right area I've moved on to investigating the fuel pressure system this morning.
Edited by dan187 on 13th Sep, 2023. |
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
13th Sep, 2023 at 09:12:14am
I have however, noticed the occasional misfire. You can see the outers go lean on this plot at the time mark.
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
13th Sep, 2023 at 08:43:48pm
On 13th Sep, 2023 Graham T said:
Looking Good Dan. For the injector sequence, I plotted this off the MS2 running on the JimStim. 
Not sure if it is of any more help. Interestingly looks like the MS2 Siamese code moves the spark event to match the injection event being moved (you can see inner vs outer spark differences relative to TDC. |
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
13th Sep, 2023 at 08:44:52pm
Thanks to Graham for hosting me this evening and talking all things Turbo EFi. Was great to find another who has jumped down the rabbit hole so deep. |
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606 Posts Member #: 1106 Post Whore Hungerford, Berks |
15th Sep, 2023 at 06:38:37am
On 13th Sep, 2023 dan187 said:
Thanks to Graham for hosting me this evening and talking all things Turbo EFi. Was great to find another who has jumped down the rabbit hole so deep. You are welcome. It was great to finally meet and interesting to see another fully sequential EFI 'A' series engine actually running nicely on the road. I love the car. It picks up like a rocket, nice and smooth. Off boost I cannot see you getting the AFR balance that much better than you have it. Maybe a little here and there. I am pretty much convinced that the missing under boost is a rich misfire. Looking at the logs of your journey home: 
The richest I saw looking through is 9.3 AFR on the inner cylinders, but I suggest that they are getting much richer than that. You will have to check the spec's but I am pretty sure that the Innovate controllers have a max and min reading and I have a feeling you are hitting that Max and then some. On the time mark in the above, you had a maximum RPM of ~ 3800 before a sharp dip in RPM before it picked up again. As TPS was relatively smooth at that point, I assume that's a miss fire. At those revs, you would have had a maximum injection window of roughly 7.8ms using 25% duty and worst case 6.1ms using 20% duty. The Pulse widths on both inners and outers was 9.997ms. I would be sure that a good portion of the outer injection pulse was getting into the inner cylinder. Whilst you are not constrained with one injector pulsing twice in a cycle (As per the MS2 Siamese code), you still have to get all the fuel in the open valve within a very short space of time in order to limit the amount of charge robbing that can happen. I think those MPI injectors are just too small to deliver the fuel you need without either injecting too early, so that the pulse gets into the still open inner cylinder or still injecting too late, after the outer inlet value has closed, hence pooling in the inlet tract and getting ingested by the inner cylinder on the next cycle. Another issue I think is going to be due to the injection strategy. If I understand the MX3x sequential injection from what you told me, you can adjust the injection timing in the table, but that applies to all cylinders and there is no per cylinder adjustment - I know nothing about the MX3 code, so I have no idea on this... Ideally, you would want to be able to model the injection timing so that you can inject sooner into the inner cylinders and later into the outer cylinders. This way you can push the injection timing on the outers slightly later to avoid (as much as is possible) getting the start of the outer injection pulse into the still open inner cylinder. But because you cannot adjust injector timing per cylinder, your injection window is actually much more limited, hence shorter pulses of more fuel are necessary. Ultimately I think you will be chasing your tail higher up the rev/load cells without getting larger injectors. regardless, nice car and it runs really well. ’77 Clubman build thread
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1267 Posts Member #: 831 Post Whore Montreal, Canada |
15th Sep, 2023 at 05:04:22pm
As Graham says, the injectors are likely too small. At best you can expect to use about 20% duty cycle which means you need injector 4 times larger than what you would in a non-siamese engine setup.
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
20th Sep, 2023 at 03:14:02pm
I like the way you’ve phrased that Jean. I hadn’t actually thought about it being the same as an MPi before.
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
20th Sep, 2023 at 03:20:08pm
Short term however, I have a broken piston to contend with (owing to the lean misfire caused by the injection style). Also the engine was struggling with excess heat I think the old water pump and rad are not up to it. Circa 108C measured at time of issue.
Edited by dan187 on 20th Sep, 2023. |
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774 Posts Member #: 6724 Post Whore Wootton Bassett |
22nd Sep, 2023 at 02:13:22pm
Bore looks clean
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