Plug leads - is thicker better?

[ratwing]

I've an open uncovered Rover V8 with a distributor and Lumenition ignition and noticed recently that there is an occasional spark jumping from the king lead so it needs replacing and since all the plug leads were bought at the same time I might as well change them too.
If the conductive core is the same size and construction, is there any practical advantage of 10mm over 8mm leads?
My present 8mm leads with black plastic spiral wrap (I don't like the blue colour) measure 12mm so size isn't a problem.

[ChrisJC]

I don't know the answer, and I suspect it will be almost impossible to get a definitive answer!

Chris.

[stevieturbo]

Most are just more insulation.

Some OEM Toyota leads are like a skinny 6mm or so, they look ridiculous. But they work.

I think there's a lot of faff about leads. As long as they're decent quality, I doubt any of them will see massive jumps in power against another.

Some ignition systems state they need a certain design of lead, but that's different ( ie, usually spiral core instead of straight conductor )

But largely, just buy good quality

[ratwing]

Cheers guys, I've not had much luck trying to find an answer either apart from the claims on various manufacturers websites.
Better the devil you know as the saying goes so I'll stick with the same 8mm Powerspark leads - I found the bill for my current leads and it's dated 2013 so fingers crossed the new ones will be as durable.

[stevieturbo]

unusual leads.....