..............So is it wise to back off bolt, then pull them, thereby allowing for break-away tork? I also used only the Permatex sealer, no 30 weight.......................Thanks
Over the recent years we have done many race engines and deal with many race cars, so re-torquing heads is a necessary item to be done often. The often asked question is to loosen the bolt/nut, or just pull to the original torque?
After talking with many "engine experts" and manufacturers that deal with high HP applications, it was the conclusion to break the bolt/nut loose about 1/8th turn, then torque to spec for the most accurate method.
Also concur to do re-torque with a cold engine.
Concerning what lube to use, the new ARP Ultra was the top choice.
On high output/boost engines we use studs as often as possible. Then minimize stress on threads in the block. Studs stay stationary when clamping force is applied. The clamping force/strength is the same, but bolts will "wear" and pull on the block threads when being tightened. Anyone working with alum blocks/heads will attest to using studs over bolts whenever possible.
Our re-torque sequence is to do it at least twice before the engine is installed. After break-in and a few heat cycles, another re-torque. Before max operating boost, but some "peppy" runs, it is done again.
After 2-3 trips to the track, or 500 street miles, is is checked again.
From there, it is a routine item like adjusting valves.
