measuring cylinder heads

If you clean the gasket surface and place the head on a flat surface with gasket face down you could put a calliper down through the spark plug hole and measure off the top of the head to the flat surface. The only thing is you need a head that has not been cut to compare unless there is a spec for what the height of the head should be. That is the only way I could think of to do it. I used to work at a machine shop and on occasion would cut automotive heads. When I was done it would always leave little marks on it, the marks where little lines left by the carbide bits, they where shaped like half circles over the head.
 
you can measure the thickness of the head, but theres error in there being if you make the calipers or mic too tight or differnt then i do.

A easy way to tell is to look at the paint on the bottomside of the head where the water rail bolts on, if they are stock it will be blue, if they are cut more then .010" the blue paint will be gone.

take a pic of the haed upside down and post it.
 
usually you can do a visual and a fingernail flick. if the heads been cut, you wont see or feel a ridge. follow the "dome" portion from where the spark plug would be down to where it flattens out to meet the cylinder. properly cut heads will be smooth all the way, stock will have a ridge.

from there you can cc the head to find the volume and hope someone here knows the amount. i dont have it for the 2000 and up but somewhere i have a note for the 98-99's.
 
The blue paint is still there. When I measure with a caliper down the plug holes it seems like I get a slightly different measurement on all 3, not much though. Should all 3 be exactly the same? All 3 have the ridge by the domes.
 
there is a tolerance so all 3 can be a differnt measurement but its not much.

the edge is idea isnt any indicator, as you have to recut the step at the edge when you rechamber a head so thats not a way you want to determine it. If it was left at zero youd have only .010-.012" squish clearance at the edge of the bore, you need at least .055" + to live on pumpgas. If i recut the head .050" flat it completely removes the bore edge, so you recut the edge in at any angle you want, and then you set the squish clearance at the bore edge at the correct clearance.

If the paint is on the bottom of them under the bottom water rail bolt hole thay are either stock or have had less then .010" taken off them so that doesnt amount to much, or for lamens terms they are pretty much stock..
 
mrviper700 said:
there is a tolerance so all 3 can be a differnt measurement but its not much.

the edge is idea isnt any indicator, as you have to recut the step at the edge when you rechamber a head so thats not a way you want to determine it. If it was left at zero youd have only .010-.012" squish clearance at the edge of the bore, you need at least .055" + to live on pumpgas. If i recut the head .050" flat it completely removes the bore edge, so you recut the edge in at any angle you want, and then you set the squish clearance at the bore edge at the correct clearance.

If the paint is on the bottom of them under the bottom water rail bolt hole thay are either stock or have had less then .010" taken off them so that doesnt amount to much, or for lamens terms they are pretty much stock..
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What is the tolerance?
 
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