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Hello all

I am replacing my ignition leads and just wanted some feedback on brand suggestions. I know the Magnecor leads seem to be popular, but I would need to special order these. The leads available in my area are:

* Federal Mogul (Champion) - $150
* Eagle Premium - $90
* OEM - $81

I can't seem to find any spec's on the Champion leads, but the Eagle leads appear to be only a 5mm or 7mm lead. I am replacing these leads as I believe the old leads are causing some electrical noise on my 12 volt power outlet (cig lighter socket), which is being transferred to my stereo by my FM transmitter. The noise disappears when the engine is off and the key is in the "accessories" position. I know there may be other causes, but I thought I would change these leads, just in case....

Are any of these leads OK, or am I best to wait for a set of Magnecor's (or another brand)?

Thanks

no contest= buy the OEM- they will last you +100km.

Running Magnecor KV85 (8.5mm) Competition leads here - they weren't cheap - about $130 when purchased about 10 years ago, but they've lasted. Running 10.5mm Queensland Ignition Leads in the other car - bought these 2nd hand from 1red5 who'd done at least 25k kms on them < Queensland Ignition Leads is now: http:/ /gregmartin dot webs dot com/ >.

Ref OEM leads, even Mazda dealer admited that they're not the best - from my experience about 50k kms.

+1 Magnecor

Forget the Champion's, that price is a joke.

93_Clubman wrote:. Running 10.5mm Queensland Ignition Leads in the other car - bought these 2nd hand from 1red5 who'd done at least 25k kms on them < Queensland Ignition Leads is now: http:/ /gregmartin dot webs dot com/ >.

QIL are top quality (they used to supply V8 Racing teams), and the fit is mm perfect, but they are expensive. The only reason why I exchanged mine was just for the sake of change.

If you are gonna spend close to $100 my vote is get a set of MSD Superconductor's from the US, as they should be around $80-$90 delivered with today's exchange rate.

It's a shame Accel no longer make custom sets cause I have a set (DIY universal kit) in the Festiva that has lasted more than 10 years, and well over 120,000km.
You can always get a "universal" set, with the correct "distributor" and spark-plug boot type, and make them yourself. Advantage of this is you can choose from about 6-7 colours (and 3-4 sizes of leads), and the satisfaction of making something for your car.

How much are a set of Bosch from Supercheap?

Hi

I think the Bosch were about $80, but they don't keep them in stock... If I have to order them and wait, probably better to get something really good. I am trying to understand the ratings on the wire etc. I had a look at a set of cheapie leads at a spares shop near work (Top Gun Leads????), which stated a resistance of about 5000-6000 ohms per metre, which I think is quite high? Does anyone know what resistance the factory leads are? I am just curious and will check my originals tonight (pretty sure they are OEM), but they may not be a good indicator as they are quite old.

I assume lower resistance = better leads? Looking at the Magnecor website, the 8 mm cables are 98 ohms per cm (3000 ohms per linear foot), so 9800 ohms per metre? Please tell me if I am wrong, as I am definitely not an electrical expert! They also list on their premium race wires (8.5 mm) a resistance of approx 7300 ohms per metre. I assume that, as the Magnecor resistance is higher than the cheaper version I saw, that resistance is only part of the issue?

I understand the other factors (heat and chemical resistance etc), but was more interested in the electrical performance properties of the cable.......

Oh, forgot to mention that price is not really the concern..... I have no other vices, so I can afford to put decent gear into my toy...... I tend to believe you often get better value with a product that is more expensive initially, but will give you better service over its lifetime.

Durability is not really the main concern either. For the low km's I put on this car (in comparison to my daily drive), I am more concerned about getting it working at its peak. That doesn't necessarily mean hanging a lots of additional performance parts from it, but it does mean getting the best from a basically stock system. Well, it is stock for now......

Noddycar- not sure where you are but Manga blue suggested to another forumite to talk to Performance ignition in Mitcham Victoria - I think that was very good advice.

Hi all

I ordered a set of Magnecor leads from he US last night (much cheaper than here and I have a US shipping address, so they will bundle it with my other gear for shipping). As I am an impatient type , I also grabbed a cheap set, as I wanted to see if it was the ignition leads causing the electrical interference on my 12 volt outlet. It was... I grabbed the Top Gun leads, as the parts guy said they were an excellent lead, but as they were relatively cheap, I won't feel guilty pulling them out when the Magnecor leads come. I'll either keep the cheap leads as a spare, or give them to my mate for his old '5..... When the Magnecor leads arrive (won't be for a few weeks, as we just bundled a heap of stuff and shipped it to Oz), I will report if there is any noticeable difference in the leads. For now, at least I do not have a horrible pulse noise through my Ipod FM transmitter..... At least I know I haven't wasted my money ordering the Magnecor's, as it was definitely the leads causing the problem. Strangely, I don't seem to have noticed any engine issues because of the leads, so I assume the factory leads had somehow lost their ability to suppress the electrical noise, but were still moving the current successfully. I haven't actually taken it for a drive yet, as I only ran it to check the interference was gone, so hopefully the cheap leads will work OK until the others arrive. Thanks to Ak Perth for the advice to fix this!

Age and heat can start to break down the shielding in the leads, probably hence why you were starting to get some humming.

An easy way to see if your leads are giving you everything they can, is to park the car in a dark spot one night and open the bonnet.
With the engine running, see if you can see any little sparks coming from the leads and arcing to the engine block or other metalwork under the bonnet.
If you can see any sparks coming from the leads, then it's time to change them.
Even though the car may still be running OK, it is a sure sign that the shielding is on its way out.

I remember trying this one night, when I had an old HD panel van that was running roghly, and seeing a really good light show going on under the bonnet!
I got scared that it might start a fire under the bonnet, so I quickly shut off the engine and left the car there until I returned the next day and changed them.

I'm interested to know how people decide the leads are stuffed, apart from interference and/or sparking visible in the dark. Rod Grainger's book says the correct resistance is 16KOhm per metre. In 3 decades of doing things to cars I have never measured the resistance of ignition leads (which probably says more about me than anything else), but it does seem to be a sensible idea. I'm so old I remember when the leads were copper cored - they NEVER lost their conductivity. Mind you, if you had a radio in your car (bloody luxury) you had a problem

Exactly how many volts do you need at the plug?

Regards,

Tim

I've always done it by resistance. Usually you'll get an acceptable resistance level based on length, think I got it from a top-gun catalog when I was just running cheap leads on my old car. Haven't checked the magnecores yet on the Mx5... Cars is running very smoothly though so I haven't seen no point. Luckily the NB8B only has 2 leads (COP for the other two) so it wasn't too expensive to get the KV85's.

physically, heat and oil will cause the plug boots to perish.
The lesser quality the lead, the lesser quality the plastic/rubber used, thus the quicker they perish.
I helped a friend change his igntion leads one day.... it took an hour.
Cheap leads that have only been on the car less than a year; three boots disintegrated upon attempting to pull them out leaving broken plastic everywhere, including the cylinders. Not fun.

I have always found the genuine Mazda leads to be very poor and if you get 40000klms out of them you are lucky.

When I bought my NA6A in about 2001 it was missing under load,or more correctly just breaking down under low revs load,and when i pointed it out to the dealer he was unaware of the cause and I got a really good deal on the car.

I had no idea but thankfully others on this forum had alerted me to the issue.

I use Hurricane , Geelong made , leads and have never had any further isssues.

Peter.

My MX is 1993 model, done 165,000 k's and still has original leads and runs fine.
How come I have no issues.