Spark plug wires
- Thread starter OleH
- Start date
Trip
New Member
I've heard that before, but people don't like to listen. I'm sure there was a thread where the 'uprated' leads were the problem, and OEM ones fixed it.
I have Magnecor and Nissan leads but I prefer the Nissan leads and have run 1.95bar in the past with no problems.
I did a lot of testing some years ago , the Nissan leads are a higher resistance but this can be a good thing with a decent ignition system at low loads.
The resitance of the plug gap compared to the lead means the resistance of the lead itself has no impact at 1.9bar. If you are getting a problem with misfires then your plug gaps are probably too big or you need to fit a bigger ignition amplifier. (I know you can run 2.0bar with OEM everything but bigger gaps making low load driving smoother)
As at high loads it makes no difference and at low loads the OEM leads are perceptably smoother I prefer the OEM leads.
If I want to dress up my engine bay I occasionally put the blue leads on. I then swap back afterwards to the OEM.
Jim
I did a lot of testing some years ago , the Nissan leads are a higher resistance but this can be a good thing with a decent ignition system at low loads.
The resitance of the plug gap compared to the lead means the resistance of the lead itself has no impact at 1.9bar. If you are getting a problem with misfires then your plug gaps are probably too big or you need to fit a bigger ignition amplifier. (I know you can run 2.0bar with OEM everything but bigger gaps making low load driving smoother)
As at high loads it makes no difference and at low loads the OEM leads are perceptably smoother I prefer the OEM leads.
If I want to dress up my engine bay I occasionally put the blue leads on. I then swap back afterwards to the OEM.
Jim
Last edited:
stumo
Active Member
I'd have thought a necklass would look nicer.
And next time, shave yer legs cos it's a bit of a give away!:doh:
Dangerous Dave
Active Member
He still managed to catch you out:wuss:
There was a lad at our work who used to shave his legs, he said it was ro reduce drag when mountian biking.
A few years later after he left the company we saw on his website that it was a different kind of drag he was into!
Anyway, I don't shave my legs...... waxing is better ;-)
Disturbing... :?
Thank you, I'll try him
Measuring of leads
BTW, I just ohm'ed my Magnecor leads. They looked a bit shabby so I wanted to check if they're any good.
Lead 1 = 4.32 kΩ
" 2 = 4.05 kΩ
" 3 = 2.82 kΩ
" 4 = 2.14 kΩ
Do I have to replace them, since the results varied this much?
The OEM leads are supposed to (according to the Nissan service manual) give a resistance of 13.6 - 18.4 kΩ/m, but I read somewhere that the Magnecor ones give a lower resistance?
BTW, I just ohm'ed my Magnecor leads. They looked a bit shabby so I wanted to check if they're any good.
Lead 1 = 4.32 kΩ
" 2 = 4.05 kΩ
" 3 = 2.82 kΩ
" 4 = 2.14 kΩ
Do I have to replace them, since the results varied this much?
The OEM leads are supposed to (according to the Nissan service manual) give a resistance of 13.6 - 18.4 kΩ/m, but I read somewhere that the Magnecor ones give a lower resistance?
Ah, that makes sense :doh: I just got confused by a tutorial I saw on youtube.
Thanks :-D
:?
I'm not sure I understand that?
Resistance of cables is often specified in ohms per m.
Lets say the magnecor leads are 10 ohms/m
Lead 1 that is 0.4m would be about 4 ohms where as lead 4 is shorter at about 0.2m so its 2ohms.
red reading
Active Member
resistance increases with lenth ,but decreases with a conductor that has a larger csa, your arse about face pobody
Fine - I didn't really think about it; it just made sense to me.
It just occurred to me that to give the same resistance (absolute) between the distributor and the plugs so...
A resistance of 4.32kOhms over 0.4m = 10.8kOhm/m and 2.14kOhm / 0.2m = 10.7kOhm/m - Which means that I did get it all arse about face, but that they are actually all the same resistance for a set length.
Surely that's maths that makes sense; did I go wrong again?
It just occurred to me that to give the same resistance (absolute) between the distributor and the plugs so...
A resistance of 4.32kOhms over 0.4m = 10.8kOhm/m and 2.14kOhm / 0.2m = 10.7kOhm/m - Which means that I did get it all arse about face, but that they are actually all the same resistance for a set length.
Surely that's maths that makes sense; did I go wrong again?
Correct
Correct; I've got it wrong again, or now I have it correct? ;-)
As I said, it made sense to me that they would all be different resistances... just not that it would be better if they were all the same to give equal current at each plug. - Just as I was getting all defensive I realised the mistake I'd made.
As I said, it made sense to me that they would all be different resistances... just not that it would be better if they were all the same to give equal current at each plug. - Just as I was getting all defensive I realised the mistake I'd made.