Ignition Leads Resisance and Ohms

Handy to know, cheers Mr B

What's your views on BP ignition leads? Think I read somewhere that you wasn't impressed by the quality? Found a French supplier on eBay for £33, where as Nissan wanted £83!

Blueprint leads are no where near standard you would hope from other stuff in their range & not worth the price really
I didn't rate Magnacor that highly either considering the cost, originals are damn good & been used in some high hp builds.
Cheaper options with comments/reviews are in link below if don't mind blue or red leads >
http://www.gtir-motorsport-club.com/t3398-ignition-lead-set

Maybe a silly question but how do you know if the leads need replacing? Is the a resistance they need to be etc? I replaced them 11 years ago with genuine Nissan ones, it's only covered 30k since then.

Being original & low mileage they probably good, visual inspection & resistance check would be good, may have base values in workshop manual, 5-7-9-11 ohm short to long roughly but sure figures are in manual .
hard beat the oem leads really so not worth binning them if decent/serviceable .

Cool, cheers Mr B

This is a general rule of thumb.

Not to exceed 1,000 ohms per inch

I have just gone over my original genuine standard plug set (contact to contact, that is dissy cap end, lead length and plug length) and this is the result

1  16.5"   5.87(k)ohms = 355 ohms/inch
2  21.1"   7.61(k)ohms = 361.3 ohms/inch
3  28.0" 10.67(k)ohms = 381.7 ohms/inch
4  29.9" 11.48(k)ohms = 383.7 ohms/inch

As you can see, they are all well within the rule of thumb.

Use a multimeter over them and you should get around the ohms(k) above.

Edit: Just read Mr B's answer and the 5,7,9,11 factor is pretty close to my readings above. The only one I would question is the 9, it should probably be closer to 10, going on the length of the leads.

Nice one, that's my apprentices job for tomorrow

Got round to checking mine today:

1 = 5.55
2 = 7.35
3 = 10.11
4 = 10.94

Again all in spec so saves buying a new set!! got new dizzy, rotor arm and plugs, boom good to go kinda