Head gasket thickness

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Nbdiesel

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Ok, doing a rebuild on a truck in just bought. Had the head redone and 6 thousandth taken off and had the block decked 4 thousandth. The previous owner had the head decked when he dropped a valve seat but didn't know how much they took off. Should I get a 10 over or a 20 over head gasket? I know the decking of the block matters for compression but the decking of the head matters for injector location to bowl. I just wonder if he had another 6 thousandth taken off I would be closer to 20 over. My setup is compounds 64/65/12 over s475. 100hp sticks, Hamilton tow cam, springs,studs and HP tuner. Would I feel any lag lowering compression a little bit with a 20 over headgasket?
 
I definitely had a noticeable loss of bottom end response/turbo spoolup with the .020" head gasket. I doubt that you would run into issues with the stock gasket.
 
Check piston protrusion, to make sure there’s enough clearance to the head. After that make sure to check PTV clearance.
 
YoungDiesel27 said:
Check piston protrusion, to make sure there’s enough clearance to the head. After that make sure to check PTV clearance.
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x2, This is the only way that makes sense. Unless you just want to swing a big hammer and lower compression more than you need to.
 
Like said , piston protrusion will dictate what thickness you go with . If you know how much total was taken off the head you can get different thickness injector washers to put them back close to the stock location.
 
So measured it out and I'm at .034. So the 1.28mm gasket is recommended according the service manual. So now the question is should I get thicker washer for the injector? I took off .006 thousandth and I don't know what the other head work took off. I tried to search for bigger ones, but couldn't find any. Does anyone know where they make some, and what should you think I get? Or just use stock and it won't affect it much? I worry about the tubes not lining up.
 
Here are two pictures
 

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That would be too tight of piston to head clearance. Run stock thickness injector washers.
 
Sorry was going from in to mm. It spec out at .34mm so the service manual says use the thicker gasket if your above .30mm. Out of tolerance is .516mm. So makes sense if they took .004 thousandth off the bock that I would be .34mm of piston protrusion.
 
I'm not critiquing but check piston protrusion from the center line of the wristpin. The piston will rock in the bore.
 
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