im picking up some 600 lift valve springs for my cam swap, my cam size is 502 intake and 520 exhaust my main concern is the size of the springs, they are 1440 in size and i know stock is 1255, can i use these safely? picking them up for cheap new with new locks, retainers and of course the springs,

i heard i may have to clearence the heads for these? anyone else here use springs like these? and by size im assuming its how big around they are?

 

no none knows? need this info before i pick these springs up and waste my money, been looking on shoebox web site and cant find anything either