Jump to content
Paul W

Atom to run ignition on classic motor

Recommended Posts

Hi, silly question but I'll ask it anyway.....

I've been looking at ignition only ECUs for an old Lotus Twin Cam, the Omex 200 and (briefly) the Nodiz. Better to pay a bit more for better quality,  local support and future options around injection though so my thoughts are crystallising on the Atom. My question is: is the Atom happy to just run ignition? I can't see why it wouldn't be but it's best to ask.

Thanks for your help.

Share this post


Link to post
Share on other sites

Yes, it is a good option for doing this, I have done a few classic carburetted engines using the Atom ignition only.  If you can fit a crank trigger then you will see quite a worthwhile increase in power by getting rid of the distributor.  Also if you fit a TPS to the carbs as well you can get them to drive quite a bit nicer with the 3D ignition.

If you pick a coil(s) with built-in ignitors that will make wiring a little simpler and reduce cost a little. 

The only Nodiz I've worked on let the smoke out after 30mins of running so I'd be a bit wary of those, it may have been a 1off but thats not the feeling I got when I talked to their support guys.  I havent touched an Omex but they at least look a little more professional. 

Share this post


Link to post
Share on other sites

Many thanks for the quick and positive replies. I've decided on the Atom and will chip away at getting all the hardware over the next couple of months as money allows. I've (just now) ordered the Lotus-specific bottom pulley/trigger wheel & bracket from QED as well as the sensor and Weber TPS. After all the wear and tear I've put on the NZ EFI website doing research etc, I'll make sure to order the Atom, loom and coil from them, likely a couple of paydays from now.

Being a newbie to all of this, what are the basic inputs I need other than the crank and throttle positions? I assume at least coolant temp? Grateful for any advice. Cheers.

Share this post


Link to post
Share on other sites

Coolant temp is not essential but nice to have as you can then use idle ignition control to give improve the idle speed during cold start/warmup.  I cant think of anything else essential but keep in the back of your mind you could add something for datalogging or safety trips like an oil pressure sensor etc.  Maybe a shift light or launch control switch...

Share this post


Link to post
Share on other sites

Have been getting cold feet as it's all very new to me and a lot of 'tuners' have no interest in the older cars.The guys who work on older cars have no knowledge/interest in the electronic stuff so I feel a bit stuck in the middle.  I almost resorted to buying a Megajolt/EDIS setup as I have a friend whose map I could use and installation is very easy.  Luckily I came to senses just before finalising the purchase. I decided the best way was to just close my eyes and jump in so I ordered my Atom & loom etc 10 minutes ago!

Anyway, to my question. I'm only doing ignition right now but want to keep my injection options open. I've ordered a 2.5m loom and my thought was to terminate the unused wires after (say) 500mm into Deutsch DT connectors. I'll keep the rest of the wire so I can match the colours when adding the injectors etc later to the other side of the connectors. Does that sound okay or am I better to strip the loom and add unbroken cable as and when needed?

Share this post


Link to post
Share on other sites
27 minutes ago, Paul W said:

Have been getting cold feet as it's all very new to me and a lot of 'tuners' have no interest in the older cars

What country/city are you in?  

 

28 minutes ago, Paul W said:

Anyway, to my question. I'm only doing ignition right now but want to keep my injection options open. I've ordered a 2.5m loom and my thought was to terminate the unused wires after (say) 500mm into Deutsch DT connectors. I'll keep the rest of the wire so I can match the colours when adding the injectors etc later to the other side of the connectors. Does that sound okay or am I better to strip the loom and add unbroken cable as and when needed?

That would work but I think it might get messy once you start adding power supply for the injectors, fuel pump relay, temp sensors, etc...  If it were me I would just pull the unused wires out of the connector for now and add them back in later when you need them.  Unused wires can be extracted from the connector easily with no special tools.

Share this post


Link to post
Share on other sites

I'm in Auckland.

I'll take your advice on the wiring. Good to hear it's easy to remove and replace wires. With the fuel pump and fan etc. I'll have them running through relays wired 'hot' but 'switched' from the ECU to keep load minimal.

I assume I'll be able to get the car safely drivable to a tuner by simply replicating the current distributor advance curve etc? I'm looking forward to getting stuck in. Just got to let the bank account recover a wee bit....

 

Share this post


Link to post
Share on other sites
3 hours ago, Paul W said:

I'll have them running through relays wired 'hot' but 'switched' from the ECU to keep load minimal.

Make sure the 12V side of the relay coil is ignition switched like the diagram below.

 

3 hours ago, Paul W said:

I assume I'll be able to get the car safely drivable to a tuner by simply replicating the current distributor advance curve etc

Yep, that will be fine.  Obviously, you will need to set base timing so that when the ECU thinks it is giving you 30degs, it actually is giving you 30.

 

I will message you about a tuner.

Share this post


Link to post
Share on other sites

Plenty of love for the old stuff within the Tech support. Have a 1967 Mini on a G4 Storm in my shed and a Mk1 Cortina 2 door keeping it company.

Share this post


Link to post
Share on other sites

Slight change of plans and wanting to hear if my thinking is faulty. My idea is now to just get the car running (ignition only) on the Atom without the TPS on the Webers - pretty much just mimicking the old distributor advance curve. Why the backward step? I'm going to fast-track the injection and don't want to spend time and money setting up the Webers if that same time and money can be spent on setting up the Jenveys that have found their way into my possession. I'm assuming here that the throttle position ignition mapping for the Webers would need to be totally reworked for the throttle bodies, meaning that anything spent would be lost? I don't want to do everything at once because of the cost - I need to spread it all out over a few months, especially as there are still parts to collect. I also don't want to wait too long - the car has an ignition problem that means it's barely usable and I don't want to spend any money on the old distributor. This way, I hope the car becomes usable quickly and more easily upgraded to injection. before Christmas.

Share this post


Link to post
Share on other sites

Yes, sounds logical to me.  You are correct that the ignition map will likely be quite different between carburettors and injection so no point wasting time fully mapping ign for the carbs.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×