How bad is this and do i really need to replace it or can i get away with it? #1&5 pistons strike damage from exhaust valve.

#5

#1

 

If it was mine, I'd get a piece of sandpaper and remove the sharp edges and call it good.

Not sure if it's the right thing to do, but it's what I would do.

 

Pistons are fine but not the valves

 

Same here. I've cleaned up worse with no issues!!

 

Next question is how do i time the heads? Is it something you do before putting them on or am i putting the heads on loosely attaching the timing chains so i can rotate the cams? I have the otc6488 tool that i used before but somehow things went pear shaped.... hence the heads off