Not Ranked
Sorry looking at wrong spec numbers but
Barry R The spec on the shelby head bolts for my motor is 75 pounds. They do get only 1 torque setup. I do check but not tighten again.
I talked to a couple of machine shops and got all different torque specs with different combos on the motors.
Iron heads and iron block torque to spec in manuals
aluminum heads to iron block 10 to 15 foot pounds less on torque bolts or studs in the motor.
aluminum heads to aluminum block with bolts, 10-15 pounds less with ARP
bolts or nuts must be lubed 3-4 step adjustment to get to spec.
aluminum heads to aluminum block with studs, 15-20 pounds less on dry gaskets with lube on the threads of the nut or stud.
I have seen many aluminum heads damaged around the bolt or stud holes from over tighening on either iron or aluminum blocks. The washers and nuts do less damage than the small bolt head with washer built into them. Some times you have to use these because you can't get ARP fasteners to work.
I know Felpro is where you worked for years and may have more engineering degrees, awards for EMC, and maybe 1/4 mile trophys.
Here is what I know from working with the aluminum and shelby block, you get into the 100 pound of tork on any stud or bolt and the threads start to shift in the core and pull. My CSX#52 block has received timeserts in all the holes but the head stud holes. When the motor was built in 97 I measures the heights on the studs because helicoils IMO are not the best fastener for high tork applications. So far the studs are all under .002". I have no leaks and feel that the height change is from core movement of and in the block. 4 years with your 482 kit and no problems yet.
As you and Kieth have said you run more torque. I would if this motor had a 12.5 compression, had power boosters like NOS, turbos, blower, nitro fuel. These motors are living things and need to expand and contract under the hardest of conditions. The expandsion rate on Aluminum is faster and larger than iron. The rate of expansion is faster on aluminum than iron. FElpro makes a good gasket, I just add a little help in sealing. 8 years with sealer and lower torque readings and no failures. I could have reused the old gasket with the new stroker kit, but didn't want to take any chances and cause a failure on the stroker kit. Some of the new motors out are running torque to yield specs for heads to blocks, ( all aluminum ) and are only running about 65-68 ft torque reads because of stretch bolts and size of bolts themselves. These motor are turning 7,800 rpms. The only different is multi layered head gaskets with silicone on them for around coolant passages. Except of Vette motors that are abused, these motors are going 100K+.
I don't have a living from building motors like yourself and others but believe that some specs are for old motors that are all iron. Today is different. This is 1 spec (95 ft. pounds or torque) That I don't agree with on an ALL aluminum motor or aluminum headed motor. Some times less is more, works better and no problems. Rick L.
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