Spark Plug Gap

[2cams70]

As 20hamelan says-electronic ignition (Pertronix and Alden anyway) seems to require resistance plugs and leads. Pertronix states-in Red-on their website that resistance leads are required but the Twin Cam has short leads and resistance plugs help--that is according to Keith Frank and I, for one, will acknowledge him as an expert!

I for one have no opinion regarding this particular matter but I would caution that it's always wise to ask "gurus" the background as why they are giving the advice that they do and with this information use your own judgement as to whether or not you wish to take it on board or seek further information or not. The earth was supposed to be flat and with the sun revolving around it at one point remember!

[Davidb]

2cams70 - Pertronix-not "Gurus" that I am aware of-state, in red in their website, that resistance spark plug wires are required when using Pertronix ignition. Alden is Pertronix according to this forum.

[mark030358]

Ngk website recommends their NGK 0127 SIFR6A11 Laser Iridium Spark Plugs.

Anyone tried them?
Cheers

[Andy8421]

2cams70 - Pertronix-not "Gurus" that I am aware of-state, in red in their website, that resistance spark plug wires are required when using Pertronix ignition. Alden is Pertronix according to this forum.

Its an interesting subject, with little definitive information on the net. Including a series resistance in the plug circuit will certainly reduce the energy of the spark and consequently reduce the amount of RF interference (RFI) produced. There are also suggestions that introducing a series resistance will reduce the 'Q' of the circuit (which is true) reducing the post spark ringing of the circuit also reducing the RFI (I am not so convinced about that). Either way, a series resistance is about reducing RFI.

No one cared when the Elan came out, there was no electronics of consequence in the car to be effected by RFI, if you fitted a radio you had to fit supplemental suppression to make it work. These days, a modern car is stuffed full of electronics and there are also environmental regulations about the amount of electrical interference a product can produce. If you are going to sell a product that could impact either of these then you better make sure that your website clearly indicates suppression is required.

It is possible that the aftermarket electronic ignition system itself could be effected by RFI, but that seems a failure of design. My current view is that the suppression requirements of after market ignition systems are about regulation and impact on other systems in the car - but I am happy to be proved wrong.