I  have  the  new  BOSS  302  block  from  Ford  Performance  and  I  am  re-assembling  my  331  cu in  race  motor.......everything  has  gone  together  as  expected, except  when  it  came  time  to  bolt  the  heads  on  (AFR 185's)......I  already  had  the  Fel-Pro  head  gaskets AFR  advises  to  use  with  these  heads, but  that  will  NOT  work, seems  the  BOSS  302  block  needs  the  351-C  head  gaskets, not  a  big  problem , just  order  some  more  head  gaskets.....
But  the  instruction  sheet  with  the  block, says  and  I  quote:
" Check cylinder  heads  for  proper  steam-hole  aligment.Stream holes are  designed to  reduce  the  possibility of  steam pocket  formation. Due  to  the  large number of aftermarket heads that  can  be  used  on  this  block, you  will  have  to  check  this  and  modify as necessary". end  quote...
The  Ford  Performance   Tech  Line  is  a  joke, they  act  as  if  everyone  is  stupid  and  every  question  is  a  waste  of  their  time... An  e-mail  to  AFR  said:
  "Hello David,
 
    You need to get the gasket to mark the holes you need to drill in the head, they are referred to as steam holes in between the cylinders. ..
o-k, they  responded  very  quickly, now  for  the  $64,000.00  question, which  are  the  damn  steam  holes???????????  I'd  rather  not  ruin  a  brand  new  set  of  AFR 185  heads drilling  holes  in  them  in  the  wrong  place...........
here  are  a  few  pics, I  am  assuming  the  pic  with  the  head  gasket  on  shows  the  "steam  holes" between  the  cylinder  walls  closest  to  the  center  of  the  block????
Any  advise  on  drilling  these  holes  will  be  greatly  appreciated......Size/depth??????
Well, those  pictures  did  not  upload  for  some  reason, please  go  to  my  gallery and  you'll  see  what  I  mean, they  are  the  first  four  pictures..........
David
(David - fixed your picture links for you....ron/CW)