Discussion Starter · #1 ·
Why does FelPro and probably some others restrict the water holes in their head gaskets to BB sized holes........... probably about 1/8 inch? Any reason NOT to open em up some?
Far as I know, ALL the heads have the extra holes. NOT all the (Mark IV) BLOCKS have the extra holes. Does your BLOCK also have the holes?My 454 is a 1978 date code casting, has the three holes in the lower portion of the head for cooling, and the 1966 396 heads i am using have them also.
Yes, without the three holes along the side, you need double holes at the end.Question is, the gasket with the three holes is a felpro 8523 PT1, that has the 3 holes, that is good. In looking at the two pictures in the above post, there is a difference in the two gaskets on the ends also. In picture 2, where the "sort of triangular" water flow opening is, there is another squarish water flow hole below it.
The upper photo is the gasket WITH the three holes; the second hole at the end isn't needed. Having the second end hole blanked directs the coolant to the three smaller holes.In picture 1, the picture without the three extra holes, there is only the sort of triangular looking water flow hole at the rear of the gasket.
Yup.My 1966 heads and 1978 block both have these two openings (triangular with the squarish hole below) at the rear of the heads & block, behind the 8 and 7 cylinders, but the supposedly correct felpro 8523 PT1 gaskets, with the three extra holes, have only the triangular looking opening, and no squarish looking opening.
Picture 1 (the top photo) DOES have the three holes.Sort of a combination of picture 1 with 3 extra holes.
Leave it alone. The end hole is blocked for a reason.Do I open up this supposedly correct gasket that has the three extra holes (cut the squarish looking water flow hole)to allow water flow through both openings behind the 7 & 8 cylinders or leave the squarish hole blocked? Thanks,,,,Thud
=Make sure they are installed "This side up" because they are not side to side symetrical.
I thought the Gen 5/6 gaskets were "handed"--one left, one right.=
Actually BB gaskets cannot be installed backwards, there is no "up side"