Hey all having a problem with my car when I turn the ignition off it runs for a while then stops. Now I have used a gunson colour tune and it's spot on in mixture and timing is 5 deg at idle and still runs on what causes this any help would be appreciated thanks

Maybe a carbon buildup which will create a hotspot on the piston or underside of a valve.
What plugs are you running? Try dropping a cooler plug in to see if stops the run on?

Cheers Shane

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If it's not a Cooper S, the mini was designed to be modified!

Yep, colder plugs have helped me in the past. Also I have used Redex in the fuel tank and gunned through the carby at times. Then a quick flog out the road.

Too high an idle & too high compression will help "run-on"
Back off your idle screw a tad & drop your initial ign timing a tad. Maybe 2 or 3 degrees & that should help...
If it does then sneak up your ign a bit by bit but keep dropping idle to suit until you find a happy medium between idle revs & throttle respinse without the run-on when u turn it off

Have u got a compression tester & a taco?

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Yep I do it's idling at about 700 atm