Due to the heavy restrictions put on local small business by the mayor of Los Angeles, once again only businesses deemed "essential" are allowed to operate.
You may never have heard of Stan Dibben, but I can assure you that he knows more about spark plugs than most, and luckily for us he took the time to write a short book about the subject of spark plugs and vintage engines.
Pushrod material and weight have been the subject of much speculation over the years, mainly steel versus aluminum. Finally the verdict is in, and now the answer is...