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MG MGB Technical - HT Leads
|Can someone reccomend a type and supplier of a good set of HT leads. I would be interested to here views of Copper cored against the other types.|
|The plug leads on my MGB GT V8 engine lead a very hard life as they are right above the exhaust manifolds. I was recommended to get Magnecor and they have been excellent. They aren't affected by the heat and the HT doesn't interfere with the radio. I'm sure they would be good on a 4-pot engine too.|
The old fashioned copper leads last the longest, but require resistor-type spark plugs in order to deal with electromagnetic interference. If you want something more modern, Pertronix makes a dandy 7mm lead. It has two current paths for reliability and redundancy. Its primary path consists of spiral wound stainless steel alloy, while its secondary path consists of a carbon impregnated fiberglass center core. It has a low 500 Ohm-per-foot resistance. It also has silicone jackets to resist high temperatures, moisture, oil and chemicals, and an EPDM (Ethylene Propylene Diene Monomer) rubber inner insulation for superior heat resistance and prevention of arcing and voltage leaks. Fiberglass reinforcing braid is used for added strength and flexibility. It doesn't get better than that!
|I got some Bosch silicon leads from Summit about 10 years ago. They still work fine. I did have some issues with the conection to the coil which is the old acorn nur fitting designed for copper core, in the end I secured a washer with a self tapper into the king lead and thats worked fine for at leat 2 years.|
|Thanks for the comments. I have been having problems with misfiring. All looked OK but I thought I would treat the motor to a new set of leads as the old ones might have been the prob. The new ones I bought from a supplier I have used before and was not very impressed by them, I should have returned them as they were damaged. After fitting them, no change.|
But I think I have found the problem. Number four lead,as it comes out of the dizzy, touches the bolt on the steering shaft uni. joint when the steering is in the straight ahead position. I have moved it away from it and it seems to have done the trick. They are very close together, is this normal.
That really shouldn't happen. I suspect that the insulation on the lead is leaking, allowing the current to ground out. Get some decent leads.
This thread was discussed between 07/04/2011 and 14/04/2011
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