Re: White exhaust valves?
The white stuff is ash. My guess is your friend had a bad case of "run on" or "dieseling". which comes from burning the carbon in the cylinders on the valves......you get it hot enough and you'll find an ash residue is left behind. It can be caused a few different things a bad fuel mixture (my 1st guess)... the wrong plugs (2nd guess)... timing being a little off,,,,,(etc),,,,,