Ignition leads

[Wear Sunscreen]

Just to make people aware, ignition leads supplied by VW Heritage do not fit 1.9 water cooled engines. The longest lead is too short.

I had to pay a mechanic £30 to check after heritage insisted that they were correct. Very poor service from them.

[1664]

There's been previous threads regarding leads being too short from several suppliers. Seems to be a common cockupette. Most recommend taking your old ones with you to check if you're buying them over the counter.

[California Dreamin]

It must be a particular make of lead set because I had exactly the same experience with GSF who also insisted they were correct despite the longest lead OBVIOUSLY being short and the king lead twice or three times the length of the original.
I ended up with 3 new, one (the longest) was the original as was the king lead...not good when you're paying for a complete set....and then one of the new replacements went breasticles up less than a year later.

My solution ended up being to make my own set using quality Lucas Hypalon lead and better than original NGK plug caps which don't have the dreadful tin shields that are responsible for most of the break down issues.

Martin

[1664]

don't have the dreadful tin shields that are responsible for most of the break down issues.

I've always wondered what exact function those tin shields are supposed to achieve

[ghost123uk]

They are there to stop the radiation of radio frequency interference from the actual spark at the plugs. The sort of thing that used to cause interference on the old VHF tellies and "medium wave" radios. They also help a lot if you have 2 way radio's in the vehicle, such as Police / Fire / Ambulance or even CB radio. I leave mine on and have a tin shield around the dizzy for this reason (CB in my case )

[1664]

Aren't normal 'suppressed' leads with normal ends supposed to do that anyway?

I always though that was the point of fitting them

[ghost123uk]

It's just extra suppression. I can hear a big difference in the background crackle (on my CB set) if I use leads with no metal covers or omit the distributor shield. If you have a look at military spec ignition systems (genny sets and aircraft engines for instance) they often have the entire HT lead covered in an earthed metal sheath for this reason.

[California Dreamin]

Agreed...they serve no useful purpose lol......

The system already has supression at the king lead ends,rotor arm, spark plug lead ends, plug caps

Personally I have never experienced any discernable difference with the shields removed, as I've said in earlier posts, VW used to tell us to remove them if misfires were reported by the customer.
I guess if it really bothers you, fit R (resistor) plugs. Bosch WR7DC instead of W7DC.this will give you the radio surpression at the plug without the troublesome tin shields.
In the meantime I cannot recommend the NGK plug caps (which are surpressed BTW) highly enough. Infact I would go as far as to say, ditch the crapping metal ones and screw on a set of these BEFORE thinking about replacing leads.
Martin