Distributorless ignition using GEMS coils and Hotwire system

[DaveEFI]

D connectors have been an industry standard for many a year. Although they do come in different qualities. They are cheap because they are made in vast quantities. You'll find them on pro broadcast gear, etc. Computers these days have gone for easy plug and unplug, hence no longer using D connectors And size of course with laptops,etc
Remember there's very little high current stuff - only the grounds carry much in the way of current.

I'm not sure how easy it is to reprogramme a hotwire for any engine mods. Or later injectors and so on. After market units are designed with this in mind.

[GDCobra]

I'm not sure how easy it is to reprogramme a hotwire for any engine mods. Or later injectors and so on. After market units are designed with this in mind.

There is a (free) system called Rover Gauge which allows viewing many parameters of the 14CUX while it's working including the fuel tables.
it is also possible to download the content of the EEPROM and save it. The variaous settings can then be altered and a new EEPROM burned.
I've only used it for setting the idle speed but many people have gone a lot further with it getting into the management algorithm to tweak how the system does what it does.
Lot of people doing very good stuff and sharing with the class.
Again I'd like to get more deeply involved with this but time is my enemy as always.

[DaveEFI]

Yes - I've heard of RoverGauge, but never used it as I've not had a hotwire. But it doesn't help with your ignition. Regardless of which programmable ignition you decide on, it will still need to be installed and tuned. Unless you rely on a map the seller supplies.

[GDCobra]

But it doesn't help with your ignition. Regardless of which programmable ignition you decide on, it will still need to be installed and tuned. Unless you rely on a map the seller supplies.

But hopefully it does explain why I’m not so interested in swapping out the EFi, my original reason for investigating MS was to have a system I could tweak, now I can do that with the 14CUX I’m less bothered hence the desire just to up-spec’ the ignition by getting rid of the dizzy. Which brings me back to where I came in.


The starting point for the sparks is to get it to replicate the dizzy. That can’t be too difficult even with an off the shelf map surely? From that point I can then look at getting it tuned up on both fuel and spark.

[DaveEFI]

Brings me back to what I said earlier. You already have an MS2. That is not going to be any more difficult to install than a MegaJolt, to do ignition only, with EDIS. However, if you add something like a Quadspark to give the high current igniters, you dispense with the EDIS module and have a bigger choice of wasted spark coils, including your Range Rover ones, since you can set the dwell. Or you could add BIP 373 drivers to MS in place of the Quadspark, if you like building things. Or use smart coils like the LS1 which have built in ignitors which MS will drive directly.

[GDCobra]

Brings me back to what I said earlier. You already have an MS2. That is not going to be any more difficult to install than a MegaJolt, to do ignition only, with EDIS. However, if you add something like a Quadspark to give the high current igniters, you dispense with the EDIS module and have a bigger choice of wasted spark coils, including your Range Rover ones, since you can set the dwell. Or you could add BIP 373 drivers to MS in place of the Quadspark, if you like building things. Or use smart coils like the LS1 which have built in ignitors which MS will drive directly.

I know that would be possible but I'm not going anywhere soon with the MS2, before I even start using it I'd have to start updating software in the unit and on my PC, then work out al the complexity of the tuning software that's got a gazillion settings in 90+% of which have no relevance to my getting ignitin running but I've still got to weed out what I need and what I don't. I don't even know what a BIP373 or a Quadspark is, got an idea on the LS coils but don't think I can drive 8 from MS, only 4.

There's just too much knowledge to build up with the MS which is why I want to keep it simple, I had a look again at the manual last night and it doesn't seem to have moved on much, starts all nice and simple then starts making references and using terminoligy which I'm not party to and it didn't explain previously so I guess I'm just not in that club.

Lets face it I've grown to hate MS.

[garrycol]

Lets face it I've grown to hate MS.

Same here - that documentation needs to be rewritten by a qualified tech writer and not some amateur.

When building mine the instructions at the top of a page said to do XYZ which I did. Then at the bottom of the page it said said dont do XYZ if what a particular function - hmmm sorry too late already done - then I damage the circuit board trying to take the components back off - great.

Also have you asked the MS community for a map to suit your setup - it doesn't happen they seem to guard them like a bag of gold and low and behold anyone who has asked for a map - lots of derision.

Like you I have grown to hate it and will buy a better system of the shelf for any a little more cost and have people to assist who actually know what they are doing.

Now having said all the above - I have to congratulate Dave as over the 5 years I have been looking at MS he has been the exception and has always tried to assist which I have been very appreciative of.

Garry

[DaveEFI]

James Murray who wrote the current manuals ain't some amateur - he also writes the software. And is in the UK, and answers points directly on the MS forum.
As regards building one yourself (which I did from the off) it's generally best to read through all the instructions first regarding how you're going to configure it as regards specific types of ignition, etc Which is why the build instructions are towards the bottom of the index. It's no different for buying a ready made one. Unless you tell the supplier how it is going to be used, you'd end up with with one built for the 'norm'.
I'd agree the manuals ain't be best I've ever seen - but certainly not the worst. But do contain pretty well everything you're likely to need - unlike those for some other make ECUs I've seen.

When I started out, I looked at the MSQ files that were said to be fine for the RV8. All different. There are so many variations it makes more sense to start from the (safe) tune that comes with a fresh code install. That's why I would never share my tune. I'd not like to be responsible for any damage to another's engine.

There are some plug and play units for specific cars that come ready mapped. At a cost.

Basically, it's your choice. You can get an Omex or whatever pro installed and rightly expect it to be fine. But pay for that. But an MS DIY install, which will be a lot cheaper, requires you to learn how to.

[SuperV8]

If you already have MS on the shelf then I would use that just to run the coil packs.
Installing it just for spark control would be no more complicated than Mega jolt and it's more flexible at working with different hardware.
When ever I have had questions regarding MS I have always found the MS extra forum very helpful, and yes James Murray has directly helped on several occasions.
I do agree there is a learning curve to do it all on your own, which I personally enjoyed.

[GDCobra]

OK, I think things have got a little off track with this. The original quesstions were realted to certain aspects of different distributorless ignition systems and how to interface any candidates with my existing EFi (and, less importantly, techometer). I really didn't want to get into a discussion of MS or any other full engine management system. Possibly best to pretend I never mentioned having the MS ECU!

I've had some good advice on the pro's and con's of EDIS and non-EDIS systems so thanks to everyone who contributed on that.
I'm still not certain of how to handle the coil signal to 14CUX/Tach but assume that there must be ways around this.

I'm not really prepared to put up with the limitations of the EDIS system particularly when not running Ford (or similar) coil packs so at the moment I'll be looking deeper into the NODIZ system.
If anyone has suggestions of other non-EDIS distributorless systems I'd be happy to hear of the alternatives.

[DaveEFI]

I dunno the 14 CU, but the older 4CU will happily trigger off a 5v logic signal, if you dispense with the series resistor. A tach which was driven off the coil negative (a pulse of about 50v) either requires a diode from each of the four wasted spark coils, or a pulse amplifier to drive off a logic level signal.

I'd be surprised if you can find a ready made unit including loom that does everything you want. The NODIZ does come close, though.

[garrycol]

I've had some good advice on the pro's and con's of EDIS and non-EDIS systems so thanks to everyone who contributed on that.
I'm still not certain of how to handle the coil signal to 14CUX/Tach but assume that there must be ways around this.

There is a tach signal output on the edis module but it never worked a normal tach. So I built a module from the below diagram - works great assuming you are using wasted spark coil packs.

This signal will also feed into the 14CUX tach input.

[GDCobra]

I've had some good advice on the pro's and con's of EDIS and non-EDIS systems so thanks to everyone who contributed on that.
I'm still not certain of how to handle the coil signal to 14CUX/Tach but assume that there must be ways around this.

There is a tach signal output on the edis module but it never worked a normal tach. So I built a module from the below diagram - works great assuming you are using wasted spark coil packs.

This signal will also feed into the 14CUX tach input.

That's interesting Garry. The circuit's I've seen are similar to yours but without the resistors (as far as I can tel), effectively summing the pulses from all coils to mimic the current connection to the existing coil. I think I've also seen a diode on the output line too.

[GDCobra]

Messed up here.

[GDCobra]

I dunno the 14 CU, but the older 4CU will happily trigger off a 5v logic signal, if you dispense with the series resistor.

Thanks for the advice on that Dave, I was thinking that too, I'm no electronics expert and it's a while since I did any electronic work but I do suspect the resistor in the 14CUX loom is to stop high voltage reaching the ECU so when interfacing with a logic level signal it could be dispensed with.

Getting a signal to the 14CUX is more important than the tach', the EFi won't run without this (I don't believe) wheras the tach' is only really for convenience.

A tach which was driven off the coil negative (a pulse of about 50v) either requires a diode from each of the four wasted spark coils, or a pulse amplifier to drive off a logic level signal.

I've seen circuits available which are built along these lines (as per diagram in Garry's post) so I could buy one of these or make something up.
As I say it's been a while since I played around with electronics but I don't expect diodes and resitors have become too expensive (although I've been wrong before)!

I'd be surprised if you can find a ready made unit including loom that does everything you want. The NODIZ does come close, though.

Not for using with GEMS coils, I think it's possible if I went with Ford coil-packs but I don't expect a problem there. Loom should be minimal:
Plug to CPS (already in existence from MS project) - 2 Wires
Plug to coils, I have plugs in stock again from MS project - 4 wires.
Plug to a MAP sensor - 2 wires I think.
Supply and ground to each of the units.
Tach signal to 14CUX

I can live with that (I think, although as I said earlier I've been wrong before!) I'm more concerned with having a unit I can plug into my PC with a software interface which requires me to make the minimum of settings specific to spark control.
There are additional connections which (I believe) are optional such as air and coolant temp' but these can wait until later if I use them at all, lets face it the distributor does not take these factors into account so I'm no worse off.