24 replies to this topic

[liirge]

Hey there, 

 

I'm running a positive earth, A+ engine with a non-ballasted ignition setup. 

 

I'm looking for peoples thought's on what the best type of ignition system would be to run. 

 

The engine is not standard and has a wild camshaft and ultra light flywheel. 

 

Happy for a forum of sensible debate. 

 

A 

 

P.S. 

Please don't say convert to -ve

[gazza82]

P.S. 
Please don't say convert to -ve

Why? It's actually not that difficult and makes fitting electical extras easier.

But you can get +ve earth electronic ignition which would be my first option.

[liirge]

 

P.S. 
Please don't say convert to -ve

Why? It's actually not that difficult and makes fitting electical extras easier.

But you can get +ve earth electronic ignition which would be my first option.

 

 

Lets just say I like the original +ve earth (please don't question the contradictory nature of an A+ engine in a +ve car and wanting originality), there's also a fuel pump involved that's +ve. 

Current Dizzy in there is a 59d4

Edited by liirge, 29 January 2015 - 11:30 PM.

[Spider]

It does limit your options. About all you'll get is the Replacement Modules types (eg, Simon BBC) or I think Luminition still do a +ve Earth unit, but again, that only retro-fits in to your existing dissy.

 

I think CSI can supply on demand a +ve Earth Dissy.

[gazza82]

Think Accuspark do one too.

[carbon]

Liirge - nothing wrong with 59D as a starting point.

 

How wild is the cam and what are you aiming for as peak power rpm?

[liirge]

The cam is a Swiftune SW10. 

 

Am looking to drive the thing reliably, and be able to absolutely hoon it when I fancy. 

 

I believe at the moment I'm suffering from points scatter badly which is giving me intermittent loss of spark, I was hoping to sort that at the very least. I see that some inbuilt units also make corrections for dwell angle? that would be a very good solution. 

[carbon]

Well set up points on the right dizzy with no wear in the bearings should be good for 8000rpm with minimal scatter. Not quite as precise as the best electronic systems, but staying with +ve earth does limit your options.

 

Is the intermittent loss of spark at all engine speeds or just very high rpm?

[liirge]

it seems to occur twice during the range: Mid and then top end you can feel that it's not able to keep up spark.

Perhaps the dizzy is badly worn.

 

It feels like someone has taken the battery cable off and then put it back on quickly.  

[liirge]

It seems to do it when warmer. 

 

I was thinking perhaps the condenser is a little tired, I've seen on here this can be a symptom. I just don't want to arbitrarily replace things.  

[carbon]

I'm guessing you have you got a 'sports coil' fitted?

[liirge]

I'm guessing you have you got a 'sports coil' fitted?

Yer the Lucas gold one.

[carbon]

Try refitting an old (but working) LA12 coil if you have one, and see what this does for the misfire.

[liirge]

Try refitting an old (but working) LA12 coil if you have one, and see what this does for the misfire.

I don't have one to hand, but the Lucas coil came off a working engine. 

I do have one question: Ballast ignition, did they make the points and condenser specific to ballast and non-ballast?

[carbon]

As far as I know the points and condenser are same on ballast and non-ballast ignition set-up.

 

Are you using dynamo, and have you checked the system voltage when running engine at 2000-3000 rpm?