I'm redoing my 67 400. My machine sholp called and advised there is a crack in both heads that runs lengthwise between the two center valve stem holes. The same crack on both heads, about 1" long. Cannot be seen with the naked eye but showed up on magnaflux. There is no sign of leakage around these areas. Does anyone know if this is "normal" for these heads?? Thanks for you help. Harvey
Harvey, Back in the late 80's I had a 1969 400 that was going into my GS350. It had the same problem. I went to a wrecking yard and they had to go through several heads to come up with a pair that wasn't cracked. It seems like it was near the pedestal for the rocker arm shaft mounts - a water jacket runs close to this area???
i had this exact same problem with my 68 430, but BOTH heads were cracked, between the valve spring pocket,and the valve cover gasket area. did not lose any coolant,or run hot, so i tossed them and got my TA aluminum heads
Any cracks on a cylinder head or engine block is not "normal" although it may be common. Better get new ones that aren't cracked than throw money away on ones that are and could later fail. (and probably will) :bglasses:
the common cracks found on the early heads are very seldom a problem and usually can be pinned and cause no further problem. i have run many sets on stock or mildly built engines with no problems at all.
