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Distributorless 5K Engine


Banjo

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Hi Guys & Gals

I am in the process of building an electronic ignition system on a 5K engine, I have here on a portable engine stand.

1842988425_5KengineStand.jpg.b5011dc501a89d68c5b956a40818666c.jpg

The electronic ignition has been working perfectly in my daily drive KE30, without a hitch, for sometime.  It uses a "locked up"  3K dizzy, with an Accuspark module in it, used purely as a triggering source.  It uses the Jaycar programmable system, to provide a customised advance & load retard map.

1948325709_AccusparkDizzy.thumb.jpg.7dc2f6987754cab4d1d52292b5599c20.jpg

The next stage is to go distributorless, altogether, using the COP conversion I have carried out to the K series head.

1163596020_nodizzy.thumb.jpg.257d4afc3a0034e5831bd7113dabe774.jpg

1341403793_COPConversion.jpg.5c4d258318a50d8906a35d2a9bcb5978.jpg 

I am going to go full sequential firing (1,4,3,2) rather than waste spark, but it is easy to try, or revert back to "Waste Spark", once you've gone sequential.

I'm considering how to provide the crankshaft position sensing information.   There are plenty of aftermarket systems, I could bolt onto the front of the engine & crankshaft pulley.

1-crank-trigger.jpg.32de8214a280f55f611379ecd1300508.jpg

However, these are fairly expensive, & prone to get damaged, or misaligned, at that position on the engine.

The area I am looking at is the flywheel ring gear as a source of pulses.  Bit like a Nissan “optical dizzy”, but signal sourced from the flywheel ring gear.  .  The K Series flywheel has 106 teeth on the ring gear, which makes 212 teeth per 720 deg of rotation, which is a full 4 stroke cycle. That number, results in a full number, when divided by 4 cylinders (53) The ring gear already exists, so it just needs a sensor. I’ve cut a little hole in the bell housing to get easy access to the ring gear. 

1858101317_RingGearAccessHole.jpg.d9b3a6ffa2a25ebf4e9c0cd01d3ee24f.jpg

A synch sensor can easily be derived off the large timing chain sprocket, which I already proved, & works well.  I may even look at using the fuel pump lobe on the camshalf, if I fit an electric fuel pump down in the boot.

213377013_Synch2.jpg.166a355c2365c6dddba24e64066f0fba.jpg

1137922233_Synch1.jpg.0790d037068c01f4cd28b7cb359dc606.jpg

Some manufacturers apparently used flywheel ring gear sensing in their earlier attempts.  Research shows some European models went this way. Early attempts used inductive 2 wire sensors, but most later model cars, used Hall Effect sensing 3 wire sensors, as the Hall Effect sensor has constant amplitude, irrespective of the revs.

The commercial automotive Hall Effect sensors are pretty expensive, so if I buy one, I want to be pretty sure it will work on the K series ring gear.  I have just spent some time building a Hall Effect sensor using the model UNG3503 Hall Effect component, & mounting it with a small bias magnet, behind it, in a small aluminium tube. It took a bit of experiment to get the bias magnet positioned correctly, so that it wouldn’t switch until the ring gear tooth was in line.

UNG3503.JPG.7415b1e562c50964ecf9315b53673cd3.JPG

 

However, when I rotated the flywheel, the sensor would not turn off, due the magnetic hysteresis of the sensor itself. Probably due to the width & depth between teeth on the flywheel.

I’ve decided to give that away, & just get a commercial Hall Effect one, that I know will work, because it has been used with ring gear, in its original application.

Has anyone on here any advice, or experience, as to which crankshaft position sensors, available as a spare part . . . . , were 1.  Hall Effect (3 wire), & 2. Intended for, & used on flywheel ring gear ?

Cheers Banjo

 

Edited by Banjo
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Hi Dave,

Quote

Very cool project. I've just done full megasquirt install with custom triggering on my e30 so my knowledge may be of use. 

How do you intend on controlling all of this? 

Thanks !  I'm having fun.  I'm very happy with the programmability of the Jaycar ignition system.  It was one of Silicon Chips most successful automotive projects.  The kit was recently discontinued, in December last year, & I snapped up a few kits that were left in one store.  I recently even sold one to a fellow Rollcluber in Portugal.

The Silicon Chip project was never intended for a distributorless application.  It had one output, that triggered an ignitor, which fired a single coil, whose HT output was fed to the centre tower of a conventional dissy cap, to be "distributed to the four spark plugs, as normal.

All I am going to do is create an electron "dizzy cap", so to speak, that will direct the o/p signal to the four ignitors built into the COPs.  That's the easy bit.  I'll use either a small Picaxe, or an Arduino uP.  Just got to sort out this ring gear pickup sensor, as the integrity of that signal, is crucial to the whole system working flawlessly.  I do have a back-up plan "B" if I'm not totally happy with the ring gear sensing precision, or reliability. I could drill eight (8) radial holes in the flywheel, & fit some cylindrical rare earth magnets, alternating North & South poles, facing out. A bipolar Hall Effect sensor would pick up the south poles & turn on, & then turn off, when the north pole presented itself.  The magnets could be positioned so the period in which a particular spark plug was fired, would only be an angle, through which normal advance & retard normally operates over.  (eg:  50 deg BTDC to say 10 deg ADTC.  This would reduce considerably the possiblity of cross firing.

However, the ring gear proposal, is the simplest, & easiest. Because it is counting the teeth, which are 3.4 deg apart, (360/106 teeth) I could set the this "firing arc", to be anything I wanted, within 3.4 deg accuracy, which is not important. 

To do that with magnets, you have to redrill flywheel & reposition, if required.

The Megasquirt alternative I still have noted for my 4K EFI conversion, which is sitting on my test bed, awaiting some finishing touches.

This project is an inbetween one, which can very easily be introduced to my road car now, to see how it works in the real world. I wanted to make the mods for triggering & synching simple, that didn't require major changes to the engine, itself, for interested parties.

When I get to the Megasquirt, I'll definitely give you a yell, as I'm never interested in reinventing the wheel, if someone has been there before. 

Cheers Banjo

 

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Hi Pete,

             

Quote

My Renault scenic 2001 ran a flywheel sensor. Plenty of those in wrecking yards. The various other Renault’s also ran them.  There was a mid model update in the sensor due to issues I’m not aware of. 

Thanks for that.  Is this picture the same as the sensor on your Renault ?

1229190953_RenaultSensor.JPG.845c73e63de26291e0b0cebf11669882.JPG

This particular picture is an aftermarket one, but the same structure.

These are relatively cheap, & I can get one for less that $ 20.00.

However, I don't believe it is a Hall Effect type, as it only has two wires, according to the pics I have found of it on the net.

There was an issue with them, & Renault did make a change, as you suggested, but it was to do with the electrical connection, that vibrated, & went o/c occasionaly.

http://www.partinfo.co.uk/files/Cambiare Tips and Tricks Issue 11 PDF.pdf

http://garagewire.co.uk/news/company/fps/problem-job-renault-crankshaft-sensors/

There are numerous complaints on the net of them attracting magnetic rubbish, as there is a magnet inside them. You simply take them out, clean them, & put them back.

Actually, your suggested sensor is exactly the right shape & size, to easily be adapted to the K50 bellhousing.  It would probably require some conditioning amplifier, to square up the sinusoidal waveform, that these "inductive" sensors produce.

I'll get one & have a play.  Even if it is not electrically suitable, the case may be very useful.

Cheers Banjo

 

 

 

 

 

Edited by Banjo
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Yes that’s it. I don’t have it anymore, but periodically it would refuse to start and I would remove the sensor, clean the metal filings off the tip, and away it would go again. Mine had the earlier style. I did get a late version off a car at pickapart but never got round to fitting it before it blew the rear main seal. It was awkward to get at in a scenic. 

 

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I think you need to determine which signal your chosen "Ecu" accepts and work backwards. I've got a VR sensor on my megasquirt. is working flawlessly, but some people have trouble
with them as they generate higher and higher voltage the faster the engine goes. 

Assuming your ecu will run a VR sensor you can get bosch sensors off the E30, or various other cars. If it were me i would get a 62 tooth wheel laser cut to the same tooth profile as e30 bosch and remove 2 teeth to mimic the 60-2 tooth wheel that is on many many european cars with bosch systems. then at least you have a known starting point.

the above 60-2 tooth wheel will enable you to run wasted spark and (if you want) semi sequential fuel injection. this requires 2 spark outputs and 2 fuel injection outputs. 

If you want full sequential you will also need a sensor on your camshaft as a reset. so the engine knows which 360 degree cycle it is on out of the two in a total of 720. I think the e30 guys use VR sensors for this too. But you will need an an additional sensor input as well as the coding in your chosen ecu to make this work. Will also require 4 ignition outputs. 

 

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Banjo search for Speeduino. It's a fully programmable ECU developed in Arduino that can cost half of a Megasquirt price.

I've spent some time thinking on a distributorless ignition but what to do with the oil pump? It'll still need the shaft in there for that. And that could be used as camshaft signal for the independent ignition.

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"that could be used as camshaft signal for the independent ignition. "

The problem there is the slap in the gears between accelerating and decelerating.  The timing signal would shift a few degrees each time.

I suppose it would be as accurate as the timng is on a stock motor, maybe accuracy isn't that important.

Banjo, can't you adapt the trigger in the K series electronic dizzys we use now?? It means a bit of metal sticking up from the flywheel edge and the sensor in the bellhousing rim like you planned, but a step further rearwards from the ring gear.  It's  a knife edge strip to give a sharp impulse, rather than your circular magnet that has a broad effect. Set it on the flywheel with epoxy and have a threaded mount on the pickup to move it within a few thou, like we do with the Terratrip sensors. Actually, they work on one of the four bolts in the back of the front discs, we just put a couple of washers under it to raise the head above the other three.

electronic trigger.jpg

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Hi Viterbo,

                  

Quote

Banjo search for Speeduino. It's a fully programmable ECU developed in Arduino that can cost half of a Megasquirt price.

Thanks for the tip on the Speedinuo !  I did not realise that someone had done all that hard code work, & put it into a package. Had a quick read this morning in bed, & it looks good, & well thought out.  Could be a very competitive product to the Megasquirt, as it appears to be more compact.  The only question I found while reseaching, is that the "timing accuracy" leaves a little bit to be desired. However, firmware is always being updated, so I'm sure that will be resolved in the future, as long as the Ardinuo micro is fast enough. Bear in mind, the errors I saw they were quoting, were at revs of 13K rpm, which few on here with K series motors will ever get to half that.

Quote

I've spent some time thinking on a distributorless ignition but what to do with the oil pump? It'll still need the shaft in there for that. And that could be used as camshaft signal for the independent ignition.

The oil pump shaft is really simple.  Just get an olde dizzy, & hacksaw the top off.

1206382184_nodizzy.thumb.jpg.0c6827975514538692e8c0963bda852c.jpg

A number of people on Rollaclub, have done this. It just needs a lid on the top, to cover the end of the shaft.  Someone on here, used a whelsh plug,  pressed onto the remaining bottom of the dizzy, turned down to suit.  Looked good.  That's what I intend to do.

You could create a a trigger, synch, or sequential signal for an electronic ignition system, using a optical wheel.   I did that in a Rolla Bosch dizzy, with shaft locked up & everything removed.

IMG_5992.JPG.d0ecddca300123ab17130afeb62c9010.JPG

DSC01205.JPG.fef8b0b6decf680a29691ed9d445cd01.JPG

If it is used simply as a synch signal, to tell the ECU, that the next crankshaft trigger signal should be directed to cylinder No: 1, then a bit of slop in the camshaft chain & sprockets etc. is not an issue.

However, I was using it a trigger signal, & the strobed timing mark on the crankshaft pulley, indicated it wobbling around 2-3 deg.  It was at that time, that I decided crankshaft triggering was the only way to go.  Once I triggered off the crankshaft, the strobe was rock solid, which proved the timing chain & sprockets were the culprit, & I would never return to camshaft triggering again.

Cheers Banjo 

 

 

 

 

 

 

Edited by Banjo
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Quote

Banjo, can't you adapt the trigger in the K series electronic dizzys we use now?? It means a bit of metal sticking up from the flywheel edge and the sensor in the bellhousing rim like you planned, but a step further rearwards from the ring gear.  It's  a knife edge strip to give a sharp impulse, rather than your circular magnet that has a broad effect. Set it on the flywheel with epoxy and have a threaded mount on the pickup to move it within a few thou, like we do with the Terratrip sensors. Actually, they work on one of the four bolts in the back of the front discs, we just put a couple of washers under it to raise the head above the other three.

Any olde points Corolla dizzy can easily be turned into a synch signal, without much toil.  At the moment, the points open & close 4 times per revolution. If you ground off three of the four lobes, it will open & close once per revolution. You just then turn the dizzy around until the points open say 50-70 deg BTDC No: 1. Alternatively, if you want to go electronic, put in an Accuspark module, & grind off 3 of the 4 imbedded magnets, in the piece that normally is fitted under the rotor.

Accutally, if you used the electronic dizzy as you have pictured above . . . .

image.png.7e12743259d6d9ba8dae31fd0bb1abc2.png 

It would be so much easier than a points one, as you just grind off three of those "tips", you have highlighted, and don't have to worry about rounding it off, as you would do with the points type, as the rubbing block, still has to be in contact with the shaft. 

 

Cheers Banjo

Edited by Banjo
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Hi Dave,

Quote

If I were you I'd make a toothed wheel, bolt it to the crank and then run wasted spark. 

Been there done that !  Played with wasted spark, & have had it running successfully.

1076329372_WasteSpark.thumb.jpg.f51d36f906064720710bc4ee04b2d226.jpg

It is certainly the simplest arrangement to set up !   No distributor;  No synch signal required; No toothed gearwheel; Simple crankshaft triggering only;  Only 2 off coil ignitors  required.

Only downside is, that you need more expensive platinum spark plugs, as the spark jumps across the gap, in two of the plugs in the wrong direction, & quickly eats away the outer electrode, if normal spark plugs are used.

Nothing against waste spark. The system pictured above, worked perfectly !  Those two (2) coils are ex Commodore. The coil mounting base-plate is Commodore also, gutted & a couple of DIY AutoTune Bosch BIP317 ignitor ICs fitted, the base plate becoming the heatsink.  Crankshaft trigger is two (2) rare earth magnets glued into two existing manufacturing "jig" holes in the flywheel ( 180 deg apart), which are picked up by a Hall Effect sensor, mounted & accessible on the engine backing plate, directly underneath the coils in the above picture.  This is a mod, almost anyone on this forum, could accomplish at low cost, with noticeable improvements, even to a stock engine.

The need to fire the plugs sequentially, is a result of now wanting to use the COP conversion I have carried out on a K Series head.  The EFI system, I also want to work sequentially, so will have four (4) outputs for COPs, & four (4) outputs  for injectors.

I will then be able to compare both systems, possibly on the same engine, as swapping over to "waste spark", from "sequential", is easy.

Cheers Banjo

 

    

 

 

Edited by Banjo
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Yah but you can use the 60-2 on the crank. Then just reduce the VR trigger in the electronic distributor to 1 pulse per 720deg. This does not need to be 100% accurate. So gear slop isnt that big of a concern. And use this as your reset. This will get you full sequential:)

Or didnt taz on here adapt a Nissan cas to his 4k? That looked quite neat. Unsure on what trigger he got out of that. 

Edited by ke70dave
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