Head Bolts for 3.8 Motor

Good Day all,
When addressing the head to the block today (3.8 1966 vintage) four of the head bolts that were longer to take the lifting brackets prevent the head from seating down. I quickly realized that this was due to the hips of the bolts being too large for the block (see pic). These new bolts came from the usual suspect in Goleta at considerable cost. While I will of course get on to them Monday, I am not aware of any jag head that these could be for? Quite a struggle to withdraw them! Any thoughts?
image

There is just supposed to be one of these. Frontish left side if memory serves.

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Thank you for replying Kris.
All of the bolt passages in the head are the same bore.

… measured at the head face?

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So far as I am aware, there is only one stud with a shoulder. Exhaust side, second from front. The bore for that stud only is larger at the head gasket face to accommodate the shoulder.

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Yes and the head’s face to the block.
ILOB

Photo is from 2012.

Crimineties! THAT’S compression ratio!

:sunglasses:

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You may have to check your particular head, but my C head has 4, increased diameter head stud bores at the mating surface to allow for up to 4 dowel studs, which I did install…the second set of head stud holes from the front and from the rear are counter-bored to a larger diameter to accommodate the dowel studs. It may well be that Jag stopped producing this style of head by the time your 3.8 came along.

Thank you. I think you have solved the mystery!
The four studs with the wider hips appear correct for the Ctype head.
ILOB