Let's talk about connecting rods first...
I like to have the oil squirt holes in the rods to help oil the cylinder walls... Many of the aftermarket rods do not have squirt holes... They claim that you don't need them, but I'm not going to be the guinea pig to do their testing for them...
I prefer to use the stock connecting rods and have new bolts installed and re-machine the bores as replacing the rod bolts may cause a mis- match in the crank bore for the rod which can cause excess wear and even lock up the crank from turning if the mis-match is too much.... You can get replacement rod bolts from Mancini Racing....
Second the crank...
You can just get the stock crank reconditioned... 318's had cast cranks and they will be enough for what you are going to do with your engine... However if you want a stronger crank, you can look into a forged crank... A stock 273 crank from 64 - 67 is forged and will bolt into a 318 with no modifications needed and they are balanced for the lighter 273/318 connecting rods... If you want a beefier crank, you can look into a stock 340 crank from 68 - 72, however they are balanced for the heavier/stronger 340/360 connecting rods and you may need to get it re-balanced if you use the stock 318 rods... You can always use the 340 or 360 connecting rods to keep the balance without having a machine shop re-balance it... The stock 340 rods are full floating, where the stock 360 rods are press fit...
