273 commando Build

66fs said
The important thing is an approximate 3/4 thread engagement. @perfacar said at more that 85 ft lb of torque they were seeing block distortion. What bothers me is you were loosing torque. Maybe the ARP bolts are too long? I do know, when I ran 72 "J" 340 heads on my 273 years ago I torqued the head bolts to 95 ft lb and had no problems with Fel-Pro 340 gaskets, but I used original 340 head bolts. I think I'd run stock 273 head bolts at 85 ft lb anymore, maybe with hardened washers.
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66fs said
The important thing is an approximate 3/4 thread engagement. @perfacar said at more that 85 ft lb of torque they were seeing block distortion. What bothers me is you were loosing torque. Maybe the ARP bolts are too long? I do know, when I ran 72 "J" 340 heads on my 273 years ago I torqued the head bolts to 95 ft lb and had no problems with Fel-Pro 340 gaskets, but I used original 340 head bolts. I think I'd run stock 273 head bolts at 85 ft lb anymore, maybe with hardened washers.
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just measured the sb arp bolts and the stock head bolts .. approx 3/8" difference. arp bolt # 144 - 3602. so it appears stock bolts have more thread length and gripping forces.
Also , what did you mean by this Quote " I think I'd run stock 273 head bolts at 85 ft lb anymore, maybe with hardened washers. " ?

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