Posted by Kaegi [108.162.245.235] on Tuesday, April 11, 2017 at 12:04:04 :
In Reply to: Re: 251 Timing and Freeing Stuck Valves posted by John S [172.68.65.195] on Tuesday, April 11, 2017 at 11:39:15 :
yes. fuel before and during WW2 was almost all unleaded. octane was 70. the reason most engines designed post war is because fuel quality went way up and had lots of lead. but the flatheads the just kept putting them in regardless.