Spark Plug Leads

[HAVIN_FUN_IN_MY_4B]

After finding a couple of "burnt" spark plug leads, and being treated to an interesting light show off the offending cables, I am looking at getting some replacement leads. From the Topgun site (I came across a post somewhere here about these leads) I have discovered that available for the NL Pajero are the standard leads or some MAX 300 ones. Main difference seems to be the resistivity of the leads - std ones in the range 5-7k ohm/m whilst the Max 300's are 1k ohm/m. From a quick search of some web sites, and remembering some theory from school I have determined that the higher resistance leads will give lesser spark; Figuring that more spark has gotta be better, I was leaning toward the Max 300's, but then I wondered if doing this could lead to earlier burn out of the spark plugs. It seems that both of these leads seem to be well below the 22k ohm max resistivity given as allowable in the manual I have.

Can anyone give me some wisdom on the pros and cons of the two different leads - or a recommendation on different leads ?

Also, does anyone have any good solutions to protecting the leads as they run past the thermostat (?) housing - had been figuring on getting some sort of heatproof sheathing.

Thanks in Advance !

Greg

[Yonnee]

The stronger the spark, the better it ignites the fuel/air mixture, the better an engine performs.

You'll find the other difference between the two leads is price. The Max300 will be a little dearer, for the better quality. They're also the LPG specified lead.

You may find a slightly shorter life span for your plugs, but how many people change their plugs when they wear out. Or does everyone change them at 20,000kms? If it really concerns you, put NGK Iridium plugs in; in excess of 100,000kms between requiring replacement.

I can't see the heat from the thermostat housing effecting the leads. The exhaust manifolds, Yes, but not the thermostat. Crossfiring will also burn leads out at a particular point.


Yonnee.

[mrbitchi]

The higher resistance leads were developed as a way to limit electrical interference to your radio. Nearly all cars use these as standard.

Personally I'd only put the Max300 "wire" leads on if you were running LPG. The fatter spark is good for LPG, but comes at the expense of plug life. The Max300 is a different type of lead, not a better quality lead.

Bosch make a good lead set too.

If they're routed correctly they shouldn't be touching anything that will damage them. If you feel the need, get some flexible plastic conduit from your electrical components supplier.

[Yonnee]

The higher resistance leads were developed as a way to limit electrical interference to your radio. Nearly all cars use these as standard.

Modern radios have pretty good filters and protection from radio interference these days.

The fatter spark is good for LPG, but comes at the expense of plug life.

how many people change their plugs when they wear out. Or does everyone change them at 20,000kms?

The Max300 is a different type of lead, not a better quality lead.

Maybe poor choice of wording... Stainless wire wound round a Kevlar core and Silicone based insulation. I'll stand corrected... 'A little dearer for a different type of performance orientated lead set'.

Bosch make a good lead set too.

That, they do.

If they're routed correctly they shouldn't be touching anything that will damage them. If you feel the need, get some flexible plastic conduit from your electrical components supplier.

Agreed. A good quality lead will have good insulation properties that shouldn't crossfire, but running some protection around them won't hurt.

[HAVIN_FUN_IN_MY_4B]

From the Topgun site it appears the construction of the Max300's and the standard TG leads are pretty much the same - stainless wire wound around the core.

Greg