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P38 v8 4.6 Edis - Using Crank Sensor Instead of VR


zim

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Not sure how grounding a few wires is different from a PIP/SAW apart from it being less prone to interference? :unsure:

Not sure if MS supports this system out of the box though.

Any coil (even relays) will produce back-EMF when you switch it on & off, that's why even the relay driver circuit in MS has a ~22v zener diode across it to snuff out reverse-voltage & spikes. Scale that up ~100x to four ignition coils firing away non-stop and you can imagine there's a fair bit of noise coming back up the wire.

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You couldn't get it spot on. You can only rotate it 90°. If you look at my first picture in post #9 you will see where the torque convertor bolts onto the flex plate. These 4 bolts are accessed through the ring - which has 4 big holes.

It's a lot more work to re-rivet the thing than just move the whole lot. But yes, it's possible.

I have been making a new hydrualic pump drive so not done any more on this side of things. Going to remove my 4.2 this weekend.

G

Post up your new hydraulic drive pictures :D

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Any coil (even relays) will produce back-EMF when you switch it on & off, that's why even the relay driver circuit in MS has a ~22v zener diode across it to snuff out reverse-voltage & spikes. Scale that up ~100x to four ignition coils firing away non-stop and you can imagine there's a fair bit of noise coming back up the wire.

Hmm, interesting. I'm not very good with electronics, but would it work to have a few transistors in there so the "dirty" signal doesn't go into the ECU?

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Hmm, interesting. I'm not very good with electronics, but would it work to have a few transistors in there so the "dirty" signal doesn't go into the ECU?

It's not that simple, controlling back EMF in this type of application can be complex, as complex as the ecu it's self. That's why EDIS is such a simple solution, all the hard work has been done by Ford to produce a module that manages the high voltage & spikes and just needs 2 low voltage signals to work (PIP & SAW). Remember (correct me if I'm wrong) but the MS was never designed as a fuel & spark, just fuel.... some bright 'sparks' decided to add in the extra circuits to control coil packs due to the open source code & circuits that B&G used, same for EDIS.

Also take into account how may RV8's are running around with MS & EDIS on them these days... personally I'd stick with it cause there is plenty of support on-line if you get stuck seting it up, go down the route of COP and you may soon be SOL.... ;)

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Ah, well, life is never simple, is it?

Probably another daft idea, but could it be an option to use an EDIS8 module to control the GEMS coil packs? Does EDIS actually need a crank signal, or is it enough if it gets a SAW, and the crank sensor is interpreted by MS? I seem to vaguely recall something about SAW being an offset from the standard 10° EDIS uses, so that's probably not possible.

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You chaps are depressing me, as I bought an MS with DCD about 3 weeks ago - I wish now I had gone for EDIS.

Anyway; on the installation CD is some useful information about avoiding noise, including using capacitors on the coils as Ford do. This is a very steep learning curve for me (electronics) but hopefully it will work out OK.

I do enjoy reading everyone's posts; it is a seriously good forum!

Cheers Charlie

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Ah, well, life is never simple, is it?

Probably another daft idea, but could it be an option to use an EDIS8 module to control the GEMS coil packs? Does EDIS actually need a crank signal, or is it enough if it gets a SAW, and the crank sensor is interpreted by MS? I seem to vaguely recall something about SAW being an offset from the standard 10° EDIS uses, so that's probably not possible.

You're confusing the wiring there...

EDIS only needs 12v, ground, and the signal from the VR sensor (trigger wheel) to make sparks. The PIP signal is generated by the EDIS to tell the ECU every time it fires a coil (it's the RPM signal). In return, the ECU generates the SAW (Spark Alignment Word) signal which tells the EDIS to change the timing.

The EDIS module does not really care which coils you connect to it, I'm sure people have used the GEMS coils before but they are only coils in a different shape to the EDIS coils with a bigger price-tag and rareity attached.

In response to "can you add some transistors?" for DCD you HAVE to anyway, either VB921 or BIP373 are the driver transistors of choice as they are intelligently current limited. The problem is that you're bringing 4x high-current lines in through the ECU, so even with good isolation & protection you are still doing the electrical equivalent of letting off fireworks next door to the kitten sanctuary.

You could, at a push, make a circuit to translate one trigger wheel pattern into another and forward that to the EDIS but that would bring various issues and you'd be half way to reinventing the EDIS module anyway.

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Post up your new hydraulic drive pictures :D

Just got to bore the hole and get the internal keyway done. This is where the dog clutch goes into. Unfortunately i don't have space for a coupling of sorts. We've run solid drive for a few years now and only worn out 2 keys. So just change them regularly instead now.

Drilled and tapped an extra 4 holes in the pulley. The pulley has been machined a bit and then a boss made to fit that with a snug fit.

426399_10151562305959882_760952112_n.jpg

G

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You're confusing the wiring there...

EDIS only needs 12v, ground, and the signal from the VR sensor (trigger wheel) to make sparks. The PIP signal is generated by the EDIS to tell the ECU every time it fires a coil (it's the RPM signal). In return, the ECU generates the SAW (Spark Alignment Word) signal which tells the EDIS to change the timing.

The EDIS module does not really care which coils you connect to it, I'm sure people have used the GEMS coils before but they are only coils in a different shape to the EDIS coils with a bigger price-tag and rareity attached.

Well, my question really was if it's possibly to use the EDIS control module without a VR input, but just a SAW from MS. But I guess you answered that in your post as no :)

It would've solved the DCD problem, as MS would read the trigger wheel, and EDIS would handle the high voltage etc.

In response to "can you add some transistors?" for DCD you HAVE to anyway, either VB921 or BIP373 are the driver transistors of choice as they are intelligently current limited. The problem is that you're bringing 4x high-current lines in through the ECU, so even with good isolation & protection you are still doing the electrical equivalent of letting off fireworks next door to the kitten sanctuary.

Well, my idea with "adding some transistors" is to do this outside the ECU, so the high voltage doesn't come anywhere near the ECU. Of course, if the EMF can hop onto the transistor switching wire, it still won't fix everything.

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You chaps are depressing me, as I bought an MS with DCD about 3 weeks ago - I wish now I had gone for EDIS.

Anyway; on the installation CD is some useful information about avoiding noise, including using capacitors on the coils as Ford do. This is a very steep learning curve for me (electronics) but hopefully it will work out OK.

I do enjoy reading everyone's posts; it is a seriously good forum!

Cheers Charlie

You wanna swap for EDIS? ;)

And big thanks to Elbekko for asking the questions and everyone else for replying, by the time I get round to it, we're bound to have found a good solution.

As for the coils, the 4.6 recently got a new LR coilpack and I've got a spare as well, so using that would be the way to go.

Filip

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Well, my question really was if it's possibly to use the EDIS control module without a VR input, but just a SAW from MS. But I guess you answered that in your post as no :)

It would've solved the DCD problem, as MS would read the trigger wheel, and EDIS would handle the high voltage etc.

I don't see what is different about that than normal MS&EDIS?

Well, my idea with "adding some transistors" is to do this outside the ECU, so the high voltage doesn't come anywhere near the ECU. Of course, if the EMF can hop onto the transistor switching wire, it still won't fix everything.

Well, adding external transistors is doable, and people do it with MS, but if you're doing that then running coils with transistors in them is probably easiest / neatest. Then again, the EDIS module is an external box with some transistors...

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I don't see what is different about that than normal MS&EDIS?

The difference is that your trigger wheel doesn't have to be what EDIS wants, but just something MS can handle. That's the whole point here, find a setup to use a standard GEMS trigger wheel without modifications that require taking out the engine.

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I don't like doubling things for no good reason, like adding a trigger wheel to the front when there's already one at the back.

That's actually one of the reasons for me to go MS, because then 1 ECU will suffice to control both petrol and LPG, instead of having 2 boxes of elecktrickery.

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Ran into a bit of a problem

The P38 4.6 comes with the 4HP24 auto gearbox. I'm running a 4HP22 in my truck. I don't have the time to strip and rebuild it with HP24 internals so just going to run it until and see.

This means that that the 4.6 Torque convertor doesn't fit. It's bigger than the 4.2 TC that i removed. However the 4.2 (and 3.9 RRC) has a different mounting system for the TC. They sit a lot further from the fly wheel and use a spacer.

My initial plan was to redrill the P38 flywheel to match the 4.2 TC. Which would work, had i remembered to line up the 4 bolts that you bolt the TC on through the fly wheel holes..... I didn't, which meant that access to those 4 M10 bolts would be to difficult.

So i popped along to a friend who breaks P38's. He had a 4.0 engine and box (4HP22) that we stripped and i've got that fly wheel and TC now. It's a different mounting design that doesn't use the same style spacer.

I've also had to swap exhaust manifolds as the P38 tubular are too wide for my chassis. Whilst they were off i've put new M10 studs in, so hopefully they won't just snap when i tighten / loosen them next time.

RRC 4.2 LSE ....................... P38 4.0 ................................. P38 4.6

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602166_10151569218974882_766942651_n.jpg

735236_10151569219264882_793828605_n.jpg

G

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Woah, didn't realise the 4.0 was so much smaller, having said that, I m using the RRC 3.9 TC on the back of my 4.0... Been fine so far, fingers crossed :)

Can see why peeps go for the 4.6, can only be better, it's huge!

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Woah, didn't realise the 4.0 was so much smaller, having said that, I m using the RRC 3.9 TC on the back of my 4.0... Been fine so far, fingers crossed :)

Can see why peeps go for the 4.6, can only be better, it's huge!

You must have changed flywheel as well ? The bolt pattern that holds the flex plate, spacer and flywheel onto the crank adaptor is a slightly different PCD when comparing the RRC to the P38. The crank has the same 6 bolt layout just the adaptor thats different (the one held on with capheads).

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Yup, bolted the whole 3.9 lot to the crank, removed/replaced the spacer as you mentioned.

Cap heads were TIGHT, as duncmc found out, but a decent allen key and a long jack handle got then cracked.

I bought the engine with the TC/flywheel removed as I knew I wouldn't need it.

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Yup, bolted the whole 3.9 lot to the crank, removed/replaced the spacer as you mentioned.

Cap heads were TIGHT, as duncmc found out, but a decent allen key and a long jack handle got then cracked.

I bought the engine with the TC/flywheel removed as I knew I wouldn't need it.

In your case it would have fitted as standard. As i've had to get a 4.0's setup to make mine work. (well i hope ! it's not in yet !)

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Dropped the engine in, still got to connect it all up. The air con pump sits pretty close to the turret :blink: Tapped the air con to 3/8 and 1/4 bsp for the on board air. Also got some M20 x 1.5 : 1/2 BSP fittings for the oil cooler pipes. I'm going to use the 4.2 plenum as this is easier for little things - kickdown cable, idle control valve etc.

I've replaced the oil pump gears whilst it's been out. It had a new water pump not to long ago - hope this is ok for a rear mounted rad. The previous vee belt version was fine. I'm not running a thermostat in this and have removed the heater matrix loop. (I think it'll be ok without a stat as it previously used to run at the rad fan switch temp - 88ish. I had a 72° stat fitted. This is also only a challenge truck)

581503_10151577572654882_2022287255_n.jp

G

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G, I found the same problem with the AC bracketry, albeit in my RRC, removed it and fitted a standard LR belt for a non-AC engine, is perfect.

Obviously you need it for OBA, my only query, when looking about for OBA engine driven compressors, the P38 style was mooted as not being suitable, and the older Sanden SD07 much, much better with longer life. You may find you have more room over the other side of the engine, above the tensioner to fit it, Gwyn does a twin alternator mount for this, which may give you an idea:

http://www.ebay.co.uk/itm/V-8-EFI-Twin-Alternator-Mount-12-volt-Land-Rover-gwynlewis4x4-2nd-alternator-/180747206195?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2a155f7e33

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Cheers. I'll give this one a try. If it freaks out then we'll fit the older style which we know works really well. There is already a 12v compressor fitted as backup.

Fired her up tonight, set the trim angle to 20 - didn't start first time, but not getting an RPM reading so swapped the VR sensor wires over it fired up. Took a short time just to prime all the oil system and then ran / sounded ok. Was just running off my 4.2's msq. Tomorrow i'll get it running properly. New VR1 20/50, sitting at about 45psi when cold.

Got a few little things to sort. Need to get an end crimped on the P38's power steering hose. It's the correct shape to route around everything, my hydraulic hose with banjo is a pain to fit where it needs to go.

Also need the mushroom part of a remote oil filter, the bit that holds a sandwich plate on - not a clue where mine are, we've got a couple somewhere ! Currently using another filter to hold the sandwich plate on but won't be able to drive like this as it'll hit the diff.

Hope the hydraulic steering works ok with the P38 pump, or i'll be swapping that as well for the ZF74.

538708_10151581504499882_1527769835_n.jp

G

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