As TR Laredo stated use torque wrench to get a feel for how tight and then continue with your calibrated feel. If you're a regular diyer i wouldn't sweet the torque there just keep them even buy feel. The std manifolds crack, brake due to heat distortion not incorrect tension. You're headers will be fine without having to fuss to much.
My old X J did the same thing. Common enough for 4.0lt to break exhaust manifolds but damn their a rock solid engine Mechanically
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2011 GRAND CHEROKEE OVERLAND 5.7LT
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