Do I need them / what are they for?

[RAS]

I've had an annoying misfire that I initially put down to duff fuel.

Several fill ups later it was still persisting, so I've started changes the obvious ignition items.

So far new leads and rotor arm, but problem persists.

At each distributor connection I have a 35mm long porcelain extender, which the ignition leads connect to. I've noticed these are quite loose, they are a pain and take up what little room there is between distributor cap and header pipe. I've just removed them and touch wood the misfire has disappeared.

I've not come across them before on other cars, I assumed they may act as a radio suppressor of sorts, but the radio is fine. What are they for and do I need them?

Cheers
Roger

[A500TVR]

Hi Roger,

After going through a number of sets of leads for my 500 Griffith, most which were not correctly designed for the Rover V8 as fitted to the TVR I finally took the plunge and ordered a set from Magnecor magnecor.co.uk

Not cheap, but cheaper in total than all the 'wrong ones' that I had bought in the past.

I called them directly and their service was great.

Regards

Steve

[andyy]

Hi Roger

I had a misfire on my 500 last year and changed everything.
The last things I changed were the plug extenders - and they were definitely causing the fault.
Nothing visible but I guess that the insulation was breaking down inside the metal shroud.
I changed all 8 and got them from ACT
cheers Andy

[carsy]

Do away with the plug extenders and get some socks to go over the end of the leads. Its one connection less to go wrong. The socks offer more protection as well.

http://www.ebay.co.uk/itm/Blue-Protector-Sleeve-Sp...

[RAS]

Thanks for the suggestions.

The car is now running fine and the plug extenders were OK.

The extenders I have removed are at the distributor end. Just wondered what they are for and if I need them. I've found some Bosche ones on flebay for a Ford V6 which are part of a distributor replacement kit, but it doesn't say what they are called or what their purpose is.

[andyy]

I thought that the plug extender caps were resistive - 5K - and the ignition system needs them to function correctly?

Or have I got it wrong?

[350Matt]

the ceramic extendors on the dizzzy are a go faster mod I'm come across before - they have a small gap inside them to force the spark to jump another gap and so raise the spark energy

usually they are cheaply made and not very effective

put them in the bin and fit some Magnecors and you won't have to worry about it again

[PeteGriff]

A500TVR said:

Hi Roger,

After going through a number of sets of leads for my 500 Griffith, most which were not correctly designed for the Rover V8 as fitted to the TVR I finally took the plunge and ordered a set from Magnecor magnecor.co.uk

Not cheap, but cheaper in total than all the 'wrong ones' that I had bought in the past.

I called them directly and their service was great.

Regards

Steve

Absolute THUMBS UP for the Magnecore leads, super items. I fiited the red type a year ago with new extenders, plugs, cap, rotor and coil. They have performed perfectly for about 3000 miles to date. They are expensive but well worth it. I rang Magnecore after receiving my leads because there were not enough lead clips to make a nice tidy installation, they kindly sent FOC additional clips of what I required. Go For It.