I've just realised that I've installed new NGK plugs into my SPRINT with the book recommended gap. Considering it has a Pertronix Ignitor electronic ignition system fitted, I understand they will require a wider gap. I have no idea how much wider, so, what would you recommend?
Also, since a wider gap means a bigger spark, does that mean the spark will be hotter too? Will this be detrimental to extended running and steady engine speeds at around 100-110kph?
Thanks & Cheers,
Rob
Plug gaps with electronic ignition.
Plug gaps with electronic ignition.
Last edited by Sundowner on Wed Mar 16, 2016 11:17 am, edited 1 time in total.
Re: Plug gaps with electronic ignition.
I think the figure for Lumenition ignitions was 35 thou ( instead of the 25 thou ) so maybe start from there or look on the pertronix website to see if they have a recommended figure 

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Re: Plug gaps with electronic ignition.
35 thou is about right for most electronic ignitions,. Much bigger and you tempt the spark to track out.
Jonners
Jonners
Note from Admin: sadly Jon passed away in February 2018 but his humour and wealth of knowledge will be fondly remembered by all. RIP Jonners.
Re: Plug gaps with electronic ignition.
Thanks for answering.
I checked with Pertronix who reckon about 5 thou extra (.030) would be OK.
You gents reckon about 10 thou (.035) is the go, so I went somewhere in the middle and set them at 32 thou.
I immediately took it on a run and found that I could hear an increase in induction noise, and the engine felt somewhat more responsive.
BUT, will this mean that the engine will run hotter?
Thanks again and Cheers,
Rob
I checked with Pertronix who reckon about 5 thou extra (.030) would be OK.
You gents reckon about 10 thou (.035) is the go, so I went somewhere in the middle and set them at 32 thou.
I immediately took it on a run and found that I could hear an increase in induction noise, and the engine felt somewhat more responsive.
BUT, will this mean that the engine will run hotter?
Thanks again and Cheers,
Rob
-
- Guest contributor
- Posts: 11179
- Joined: Tue Oct 03, 2006 9:45 pm
- Location: Middlesex
Re: Plug gaps with electronic ignition.
Only if your cooling system is unable to loose the extra energy from better combustion.....
Jonners

Jonners
Note from Admin: sadly Jon passed away in February 2018 but his humour and wealth of knowledge will be fondly remembered by all. RIP Jonners.