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#Post#: 3622--------------------------------------------------
KWD's Megajolt Ignition
By: Goose Date: January 12, 2012, 2:17 am
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So, after being inspired by OTLY, ex of this parish, this is a
conversion I have been meaning to do for some time, but i'm only
just getting round to it. I aim to keep a record of the
instalation, and the results here. This will be going onto my
2.5 petrol engine, which is running a 2.25 timing cover etc.
What is it? Well, as some of you will know, there is a another
type of fuel available, other than diesel. It's called Petrol,
because it's made from refined pets. This type of fuel
requires electricty to make sparks, in order for it to explode
at the right time and produce power. Making this spark happen at
the correct time, is really rather difficult, and in the old
days they used a device called a dizzytributer. This device is
full of points, condensors, rotor arms and centrifugal weights
and advances. In the olden days they were accepted as being
adequate. Alas, these days they seem to be made from cheese,
and wear out and break often. Yes, a good one is fine for a land
rover engine, but I suspect there should be a bit more power and
economy to be had from having a stronger, more precise and
accuratly timed spark.
As my dizzy is a useless peice of badly made shite, I have
decided to retrofit the ignition system off of an old 1990's
ford. This ford system is called an EDIS system, which stands
for a string of pretty dull words. It does away with the
distributor entirely, and instead it has a magnetic pickup
mounted to the crank pulley. This sensor reads the position of
the crank using a toothed wheel, which is designed with one
tooth missing. As the teeth pass by the sensor, something
called the Hall effect (After it's discover, the Emeritus
Professor of Engineering DaveH). What this means is, that as the
teeth pass the sensor, a electrical pulse happens. This pulse
is fed into some electronics, and then lots of magic happens,
which I won't bore you with, and sparks happen in the correct
places. This also means that you no longer have any mechanical
slop and wear between the crank, camshaft and dizzy drive to
worry about.
The Megajolt itself, is a tiny programable box, that interfaces
with the EDIS system, and allows you to create and customise
your own igniton maps, so you can very finely tune your petrol
engine, and get the most power and efficency out of it. It will
also allow you to select between 2 maps, so you can have one for
petrol and one for LPG. It does a multitute of other things too.
All of this means, that I will no longer need a distributor, and
I will no longer have to muck about with points and timing. But
"Hah!" I hear you say, "You've now got a load of complicated
electronics to go wrong instead, you fool!" Well, yes, I
suppose. But the actual system itself is pretty simple, and
there are no moving parts to go wrong. If the megajolt goes
wrong, then the EDIS system simply switches into "limp home"
mode and sets the timing to a static amount. And you can leave
the distributor in place, so you can always just swap the HT
leads over if you must, But I would hope the megajolt and EDIS
system should be far more reliable than the pants �19
distributors you can buy are.
I appreciate this system isn't for everyone, but electronics is
what I do, and I fancied the challenge, and I am keen to see if
there is any improvement, or if I'm about to waste a few weeks
of work. So if you're interested, read on....
The bits!
This is the basic EDIS system, as it is when ripped out of some
old Ford:
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2613.jpg
On the left, is the connector for the EDIS module, along with a
section of the required wiring loom. In the middle, the big
plastic brick thing is the EDIS module. On the right, is the
coil pack. This has 4 HT lead sockets, for each cylinder. At
the bottom is the "VR sensor" which is what reads the position
of the crank shaft.
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2615.jpg
A closer look at the VR sensor, it's just a plastic lump with a
magnet and a coil inside.
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2616.jpg
The EDIS connector. Starting at the left, we have 3 wires for
the coil pack and the tacho. The brown wire is ground, and the
black is +12v (Ford wiring colours are retarded) The next 2
blueish wires are for the VR sensor, and the rest go to the
megajolt.
Speaking of which,
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2619.jpg
Here is the wee beasty, all assembled. The thing that looks
like a phone socket is where you plug your laptop, and the other
thing is the vacuum advance from the manifold.
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2622.jpg
On the back is a complicated looking connector, that allows you
to interface with pretty much everything, and also connects to
the EDIS system (Although, you only acually need 2 wires
connected between the EDIS and megajolt)
Next, you need to mount the trigger wheel:
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2626.jpg
.... to the crank pulley:
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2625.jpg
I took my crank pulley to a chap called Bob, who is a very
clever man who is an automotive engineer. (Cheers FenTiger for
putting me in touch with him). Whilst we drank tea, and bob
regailed me with stories of making wooden pistons to get out of
the desert in Africa, he trued the pulley up on the lathe, and
spun a resess into it, to allow the toothed trigger wheel to fit
centrally, with mimimum run out. He did this all the old
fashioned way, and needless to say it fits perfectly. Top bloke.
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2629.jpg
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2632.jpg
Once I have worked out the correct position, this will be welded
on.
Next, I made up a rudimentary precision engineered bracket for
the VR sensor. This was made from a rusty old bit of steel
found in a skip, and bent into a right angle.
Trial fit on spare timing cover, shows it should work ok,
hopefully:
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2637.jpg
Conveniantly, there are 2 threaded holes on the timing cover,
which are pefect for mounting the sensor onto.
Thats all so far, I hope to get more done in the week!
So now you're all really enthused (or appalled) you'd maybe not
want to know where you can buy all these bits!
Well, eBay is where I bought the second hand EDIS system. You
want one thats still complete with the nice waterproof ford
connectors if possible, rather than one someones butchered with
side cutters.
The megajolt box is available from
http://www.autosportlabs.net/Main_Page
http://www.autosportlabs.net/Main_Page
Which is in America. You
can buy it as a kit form, or readily assembled for a bit more.
The trigger wheel is from
http://trigger-wheels.com
http://trigger-wheels.com
Who sell a wide range of wheels and
parts (including ready made megajolt boxes) I have used the
5.75" ring wheel.
I have yet to actually touch my land rover with this
instalation, as the timing cover was a spare, and the pulley was
a new one (my old one is wankered and leaking oil) from
craddocks. So the next job is to get that bastard crank bolt
undone, and get the existing timing cover (which is also fecked)
off my engine.
I'll keep you posted on my progress, and I hope at least some of
you were not bored to sleep...
:D
#Post#: 3623--------------------------------------------------
Re: KWD's Megajolt Ignition
By: Goose Date: January 12, 2012, 2:21 am
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No photos tonight, as I forgot the camera. But I got a few bits
done. The crank puley nut is off, using the wedge a bar on the
chassis and blip the starter motor trick.
I also made up a vacuum take off from the manifold, as the
megajolt requires direct manifold pressure, rather than ported
manifold pressure, which is what you get from the standard
vacuum advance when taken from the carb. As described on the
megajolt website:
[quote]Most vacuum advance takeoff ports are designed in such a
way that vacuum is measured through a hole, which is actually
covered by the edge of the throttle plate at idle. That is
called Ported Vacuum. That is done to cut off all vacuum advance
at idle, which in turn slows the engine and makes it easier to
achieve stable idle with the tiny throttle plate opening used at
idle. Vacuum measured on such a port, therefore, has no vacuum
at idle, moves to maximum vacuum just off idle, and then
decreasing vacuum as the throttle is opened further. The
discontinuity just off idle makes such a port awkward to deal
with on the load map.
You can test whether you have ported vacuum or not: pull the vac
hose off the vacuum advance unit. With your finger over the end
of the hose, you should feel vacuum with the engine revved above
idle. Assuming yes, let the engine speed drop back to idle. Is
there still vacuum? If not (most likely), that means you have
ported vacuum, and should find another source of vacuum,
somewhere on the manfold. [/quote]
So I have used the take off that would be used for a brake
servo. This should work perfectly.
Other stuff I have done is to paint the timing cover (yes... I
know..) and also start to work out where to locate the parts in
the engine bay. I also managed to brand myself with an M5 bolt
while cutting some down.
The plan is to get everything ready to fit, and then swap over
the pulley and timing cover in one go, without having to leave
the engine open and exposed to dust/rain/chickens/etc on the
farm.
I'll head down after work tomorrow and get a bit more done
hopefully.
#Post#: 3624--------------------------------------------------
Re: KWD's Megajolt Ignition
By: Goose Date: January 12, 2012, 2:21 am
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Tonight I mounted up the coil pack and EDIS module to the
bulkhead. I've mounted them up nice and high, in the hope they
stay dry. Having said that, all the connectors are supposedly
waterproof, so I am hopeful they should be better than your
normal dizzy in the wet.
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2639.jpg
No, i've not stuck it on with blue snot, that was just so I
could line up the holes to drill for the screws that hold it to
the bulkhead.
I also made a start at the wiring. The plan is to run all of
the wires into a plastic housing, where any connections will be.
The idea behind this is to keep water off the connections, and
to also neaten things up a bit. This is the box i'll be using:
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2641.jpg
I plan to mount the megajolt box inside the cab, in the dash
tray, to keep it safer from mud and shite. There are only a
couple of wires, and the vacuum advance to pass through the
bulkhead to the megajolt.
Vaccum advance, bodged out of bits of pipe. Works well enough:
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2640.jpg
I'll carry on with wring things up tommorow, and then come the
weekend I'll get on with swapping the timing cover over for the
new one.
Cheers!
#Post#: 3625--------------------------------------------------
Re: KWD's Megajolt Ignition
By: Goose Date: January 12, 2012, 2:23 am
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[quote]For the parts, what Ford's are we talking about - model /
year? [/quote]
These ones! And possibly others too.
So, EDIS-4 is for 4cyl engines, EDIS-6 is for 6 cyl (V or
straight), and EDIS-8 is for the V8 folks.
EDIS-4
Ford Escort
Ford Fiesta
Mazda 121
Ford Escort
Ford Sierra
EDIS-6
Ford Ranger Pickup truck
Mazda B-Series Pickup
Ford Explorer
Mazda Navajo
Ford Aerostar
Ford Scorpio 2.9 Cosworth
Ford Mondeo V6
EDIS-8
Crown Victoria
Mercury Grand Marquis
Lincoln Town Car
Ford Thunderbird
Mercury Cougar
Ford Mustang 5.0
[quote]can i just ask what happens when it all gets wet and
muddy?[/quote]
Well, i'll soon find out...
Seriously though, as I mentioned earlier all the conenctions on
the ford loom have rubber seals around them, and are supposedly
water proof. Any additional connections I am making will be
made inside a splash proof junction box, as shown above. The VR
sensor is a sealed unit, and it's just a magnet. Water shouldn't
really affect it. I am more worried about the toothed wheel
picking up a lump of shit and clouting the sensor with it. The
coil pack is a sealed unservicable unit, as is the EDIS module,
so these shouldn't have a problem. The large connector on the
EDIS module is a sealed plug too, and i'll be wrapping it up a
bit better once i'm done. The megajolt unit is definately not
waterproof, and for that reason it'll be mounted in the dash
board, (mostly) out of harms way. I'm also considering filling
it with jelly wax, which will waterproof it and keep moisture
off the electronics.
I can't imagine it being any less waterproof than a dizzy, and I
hope it should be more resiliant to water. If it does all go
tits up, I'll look into mounting all the components into a
waterproof box, but I hope this won't be needed.
Having said that, the dizzy did cope with this act of stupidity:
http://i654.photobucket.com/albums/uu264/Goose76UK/bits%20n%20bobs/n745570051_2…
:lol:
#Post#: 3626--------------------------------------------------
Re: KWD's Megajolt Ignition
By: Goose Date: January 12, 2012, 2:26 am
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[quote]I thought running EDIS for V8's was similar to the 4
cylinder version but it just ran a wasted spark.
[/quote]
The EDIS system is a wasted spark system anyway. I think for
the V8 system you just have 2 coil packs. I guess the module
must be slightly different too. But I've not seen one. There
will be lots of information available on the Autolabs website
though.
http://www.autosportlabs.net/MegaJolt_Lite_Jr.
http://www.autosportlabs.net/MegaJolt_Lite_Jr.
[quote]when mine was petrol the dizzy coped very well in water
if it didnt it dryed in 5 mins it seemed a little water was
worse thaan lots as starting on damp days was its worst
downfall.
i like the idea i just like things as simple to fix and the less
wires the better i think? depends what u want i supose
[/quote]
Cooper - To be honest, there really isn't a huge amount to go
wrong. There are no moving parts, it's just electronics, and
compared to modern ECU systems, it's very simple. And if they
go wrong, then it's not too hard to replace. You can just swap
the HT leads over to the distributor and run as normal if you
need to.
I appreciate it's not for everyone, but I work in Electronics,
so I obviouslty find it easier to get my head round whats going
on with it. It might turn out that i've wasted a couple of
weeks and it's unreliable and rubbish. I really hope it isn't,
it shouldn't be, but I won't know until I try! :)
#Post#: 3627--------------------------------------------------
Re: KWD's Megajolt Ignition
By: Goose Date: January 12, 2012, 2:27 am
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[quote]How does the map switching work? can you switch between
say a LPG and petrol map "manually" - or is it a case of
plugging a laptop in and swapping them over?[/quote]
Yes, you can switch over on the fly. There is a pin on the
connector called the option pin. All you need to do is wire a
switch to it, that pulls the pin high or low, to choose between
ignition maps.
#Post#: 3628--------------------------------------------------
Re: KWD's Megajolt Ignition
By: Goose Date: January 12, 2012, 2:28 am
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Right, so it's in and done, and it rocks! :8):
I had a mammoth session on it this weekend. Firstly, I set
about swapping the timing cover over. This wasn't necessary for
the install, but seeing as I had the crank pulley off, it seemed
like a good time to do it, as the seal was leaking, and someone
had stripped the threads on the holes for the sump bolts. So,
alternator off, water pump off, crank pulley off, and then off
with the timing cover. Fit the new crank seal to the
replacement timing cover, and refit everything.
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2644.jpg
I then trial fitted the crank pulley, and lined the trigger
wheel up to the sensor. With the crank at TDC, the timing wheel
needs to be fitted so that the missing tooth is 90 degrees ahead
of the sensor. (This is different for 6 pots and V8's.)
Once I was happy it was in the right place, I went over to
FenTigers house, where he fired some weld at it for me.
Obviously then I had to paint it. The result:
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2643.jpg
Then on Sunday, I fitted the crank pulley, and put the rest of
the engine back together, and refilled the rad. Next I finished
the wiring off. As I mentioned above I made a junction box, to
hold any connectors in. This tidies up the install and also
keeps muck and shite off the connections, not that there are
many. Below you can see the coil pack, EDIS module and my
junction box.
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2646.jpg
At the bottom you can see the vacuum advance hose disappearing
through the bulkhead. I'll add a grommet at some point.
Once this was done, and before connecting the Megajolt, I
decided to fire the engine up. It should run in limp home mode.
And, to my surprise it fired up straight away and sat there
purring at a static 12 degrees advance. Spurred on by this
success I decided to fit the Megajolt
Installing the megajolt itself is dead simple. You only need 4
wires for a basic install. These are +12v, ground, PIP and SAW.
The PIP and SAW lines go between the EDIS module (pins 1 and 3)
and the Megajolt, and are the only wires needed for the two to
talk to each other. It's important to note, that you should
power and ground the EDIS and Megajolt from the same points, as
to avoid earth loops and other electomagical phenomena.
Here is an overall view of the system, pinched from the autolabs
page:
http://www.autosportlabs.net/images/3/35/Megajolt_system.jpg
And here is the basic wiring diagram:
http://www.autosportlabs.net/images/5/59/EDIS_Module_harness.png
There are a few differences between 4,6 and 8 cyl versions.
Here is the Megajolt, wired in. The white wire at the top is the
serial cable, for plugging into a laptop.
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2647.jpg
After 5 minutes of wondering why nothing was working, I plugged
the power back in and it started up fine. With the laptop
plugged in, you can be a real anorak and watch the digital RPM
gauge and load values going up and down in real time etc.
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2649.jpg
Note the laptop running off the dash sockets, due to a fucked
battery. Only problem is, it switches off when you press the
starter! :roll: On the screen is a 3D graph of your ignition
map, with pointers that move about n that.
And here is s nerdy graph of a drive home from Kev's house back
to mine. All those lines mean stuff. Apparently.
http://i654.photobucket.com/albums/uu264/Goose76UK/Megajolt/IMG_2651.jpg
I'm currently running OTLY's ignition map, and it runs
brilliantly. It starts easier, needs barely any choke,
accelerates far smoother and quicker, has more torque and more
power. It's a real noticeable difference. With the strobe gun
on the pulley, you can see that the timing is as steady as a
rock. No more jumping about and generally being shit.
I suspect there is a lot more performance gains to be had out of
it, once I start tweaking the igniton map a bit. But for now,
it's running brilliantly. I'm very pleased with it, it's
difficult to describe just how much of a difference it's made to
how well the engine runs!
I'll keep you posted of how it runs over the next few months.
Cheers!
#Post#: 3629--------------------------------------------------
Re: KWD's Megajolt Ignition
By: Goose Date: January 12, 2012, 2:33 am
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Just an update to this archived post - I've done nearly 15000
trouble free miles now with the Megajolt, and I'm really pleased
with it. It runs so much smoother, pulls harder and never goes
out of tune. It's also survived a fair amount of abuse and
drowning off-road too. I have now also fitted a switch on the
dashboard that changes my ignition map, depending what fuel type
I am running. So I now have a custom map for LPG and one for
Petrol. This means I don't have to try and compromise betweeb
the two.
Can't recommend it enough!
#Post#: 3791--------------------------------------------------
Re: KWD's Megajolt Ignition
By: Doug_T Date: January 12, 2012, 10:48 am
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Nice 8) I too intend to go down the EDIS road when I get the
new cam in. One question: what did you do with the now
redundant Dizzy, have you left it there? I was thinking of
getting the vacum pump off a 2.5/200 and putting that in place
of the dizzy to give me my brake vacum, and using the inlet
manifold takeoff for the vac advance as you have done.
#Post#: 3792--------------------------------------------------
Re: KWD's Megajolt Ignition
By: Goose Date: January 12, 2012, 10:51 am
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Hi Doug,
I've taken the internals out my dizzy and left it there. It now
just serves to fil the redundant hole in the engine! Also it's
handy as a backup just incase something goes tits up, although
it hasn't yet! Touch wood...!
Fitting a vacuum pump sounds like an excellent idea!
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