340 cylinder head bolts need washers?

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*OEM come without washers.
*Correct flat washers can be used to help spread the load and get the bolts torqued more accurately.
*No such thing as "lock" washers for cylinder head bolts. Proper torque is used to keep everything right. Some recommend retorquing the head bolts after warm-up.
* Do not use Lock-tite on head bolts. Only lube and torque to specs based on the lube used.