Posted by Chris Case [76.212.214.193] on Thursday, July 28, 2011 at 21:59:46 :
In Reply to: Re: be carefull on milling the head posted by kaegi [71.231.127.14] on Thursday, July 28, 2011 at 11:48:05 :
IIRC, stock flat head spring on had 35 pounds of pressure on the closed valve. Modern engines run about 75, hi-po may be 110.
Bigger springs would keep the valves from floating, getting high end power than the 35 pounders, taking advantage of the better cam.