I ran the "AN" type bolts on my racecar for a while. They didn't seen to
do well after being torqued a few times. I had head gasket
failures several times. What finally worked for me was I drilled everything
up to the next size and tapped the holes with corse
theads to accept head bolts from ARP. The torque on the ARP bolts
is 80# instead of the 48# for the stock Rootes bolts. Never had to take the
head off again after that. Note that some of the bolt holes through the head
had to be opened up for the larger bolts. I also have a set of ARP bolts in
the standard Rootes diameter but they are not fine thread. Maybe they could
be used with a helicoil to alter the thread style. Perhaps ARP could make
some in the correct configuration.???
Brent Edinger
_________________________________________________________________
|