Useful Thackers, but these are the same carb setting results on two plugs of the same make, just different heat ranges............
If I remember correctly, B7ES is a hotter plug than B8ES so you are just seeing the result of a better 'burn ' on the B7 than the B8..........or that's how my thinking is going at the moment.
On a cast barrel, like yours, I wouldn't go down to 2%, maybe 3% unless your using a fully synthetic oil. Just MY opinion tho'.
In my case, the barrel is nicasil lined with alloy jacket so I'm not so concerned about seizes, more with piston crown 'melts'.
In the final analysis I'd rather the engine ran a little too rich than too lean.........
Anyone else
