[the walrus]

Why is there such variety offered for head gasket bore sizes. Is there an advantage to oversizing the bore. For a 454 the most popular size offered seems to be 4.52". I am building a 0.030" over 4.25 bore for a final size of 4.28" bore. Should I be looking for a smaller gasket bore ???

 

[Bad Rat 414]

I believe you can get one in a 4.370". I try to get as close as the bore size as I can.

 

[Wolfplace]

I believe you can get one in a 4.370". I try to get as close as the bore size as I can.

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This is normally correct but you have to be careful with some of the new CNC chambered heads.
AFR for one takes the 4.540 like a 1017 regardless of bore size.
The fire ring will hang into the bore with the 4.370.