Reworking Flathead Head Domes

I put a set of EAB heads on my '51 Merc and after claying found
that there was zero clearance between pistons and heads with a gasket on.
Couldn't find anyone to redome heads so I decided to play around. From what
I heard .050 -.070 cl was ok. Took a die grinder with a thin cutoff wheel and
made approx .05 deep plunge cuts around the dome . Then went in with a radiused grinding stone and cleaned out the pockets to the depth of cuts. I know this is crude, but how accurate does it have to be? I clayed the heads again and measure within .05-.07. Figured the heads were probably junk anyway. Toss them or what? Engine has Egge pistons, Schnieder cam, .06 over. Didn't want to use 2 gaskets.

 

Added pics

 

Is it a 4" stroke?
Are they Merc pistons?
I know this sounds like a dumb question, but you never know.........

 

Yes,that's what the box had written on it.

 

The trick is, if you put Ford (3-3/4" stroke) pistons on a Merc (4") crank, you'll have this exact problem - piston pops up about 1/8" higher than it should...although certainly not impossible, nor outside the realm of probability, it would be at least slightly unusual to have heads cut this much...stockers seem to have around .100" clearance, so that's why we're asking which pistons on which crank...

When looking at heads that may have been cut, try to use an old gasket to lay on them & see what the size of the dome is compared to the gasket outline - that should give you a ballpark idea of what you're working with - small piston dome relief = major milling & probable issues.

 

If they were Offys I could domb the **** out of them.Iron heads are kind of thin above domb.You could have used thicker head gastkets.Useally you have a reverse situation from what you got. What you have with right head might be the hot set up.How hight does piston domb rise above block?That nunber should tell the tall on piston pin hight.

 

Piston dome is approx 3/16" above block.

 

3/16 =.1875 is normal flathead domb, some one milled heads.I would run it after you cut,whats 050 amonks friends.Wouldn't put a blower with those heads.

 

i had clearance issues with egge pistons and offy heads...had about 030 machined from the piston crown to 0 at the edge. so far it runs good. where in smalbany are you? im out in east schodack...