HI ,

how does one know what thickness copper washer to install on the injector to head seat ?

looks like my stock ones were .060

saw they make diff thickness ones why ?

thank you !

 

The thickness of those washers affects the spray pattern in the bowl of the piston, thicker washers it will be wider when it hits the bowl and thinner will concentrate the spray into the center of the bowl. If the truck is all stock never had the head off or shaved, I would stay with the stock thickness. I would say that someone more knowledgeable about this will chime in soon but not so sure of that anymore. I have read that you can heat those copper washers up to glowing then let them cool and they will work like new.
This is what google says about it.
To anneal copper washers, heat them with a torch (propane, MAP gas, or a stove) until they reach a dull cherry-red glow, which softens the metal. Immediately quench the hot washer in water to remove heat scale and create a soft, pliable washer that provides a perfect seal.