Aftermarket HT leads manufacturers make lots of claims, do they make any sense? Let's see what a reputable brand has to say, and how a standard OEM replacement set test out.

Check a misfire & replace HT ignition leads:    • How to: Check a misfire & replace HT ...  

Find articles referenced here: https://www.magnecor.com/magnecor1/ma...
(no affiliation)

High tension leads (cables) are a service item really and should be replaced with a new (not used) set. Try Amazon ~
US: https://amzn.to/39FPaYB | UK: https://amzn.to/2Q1kidq

If you need a coil pack ~
Amazon US: https://amzn.to/2IxadAz | UK: https://amzn.to/3aC8BSa

(Using the above Amazon links helps support my channel and is appreciated!)