Torque Specs
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Torque Specs
I need to tighten my crank shaft pully bolt to torque specs. Well Ford's procedure is garbage. It can't be simple and give me an actual number for the final torque. It just says torque to 66 ft lbs, loosen one full turn, torque to 37 ft lbs, tighten another 90 degrees. I'm wondering if Ford was drunk when they came up with these instructions. So finally here is my question, what do you guys think that is in ft lbs? The previous body style Mustang uses 116-121 ft lbs of torque, I'd assume that it'd be some where around there.
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From: Cabot, AR
It is the correct process when you are using the "Torque to yield" procedure. In this case the bolts are actually stretched just over the point where the metal starts to deform. Also note, in this process the bolts are NOT reusable.
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According to Ford's work shop manual the bolt is able to be used twice. I understand the point of "Torque to Yield" but why not give a torque spec for the final value? According to Steeda, like the previous body style, 120 ft lbs of torque will be good but it just doesn't make sense. If you're torquing to 66 ft lbs to set the pully, than backing off, it should be less than 66 ft lbs, correct? But I know that's not right because the impact barely broke it loose ...
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From: NW Indiana
Because after its torqued the first time you have to follow that magical sequence to get it back to the factory torque setting. There is no torque value for a TTY bolt that can be re-used. We do this with head bolt on Cummins. Its always 90 degrees after final torque to ensure it make sup for the amount the bolt may have been stretched. they dont know how far its stretched, so you torque it to spec, then another 90
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Just spoke to someone at Steeda who actually knows what their talking about. According to him Ford revised the proper torque procedure for the bolt and made the final torque value 100-110 ft lbs.
