Correct Exhaust Manifold Bolts

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Kilian

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Hey folks, looking for some help in the correct hardware to use. I'm switching back to OEM exhaust manifolds on my 350, and wondering what hardware to use. The engine had headers on it and those bolts are too short for the cast iron manifolds.

Is there a kit sold with the right hardware? (not sure if it makes a difference, but the engine is vintage mid 70s being used in an 83 GMC). Parts catalog calls out 3/8-16 x 2-3/16" bolts...will Gr8 3/8 x 2-1/4 bolts work? Any kind of lock washer or flat washer used? Thanks for the help.
 

Grit dog

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Yes there are multitudes of suppliers that sell small block manifold bolt sets for $25-40. Even Amazon has multiple options for less $ and sitting on your doorstep tomorrow. Can’t be much if any savings to buy a dozen grade 8 hardware store bolts.
Plus you can get a set that has threaded studs on some if needed.
 

SquareRoot

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Part #HOK-8525HKR is just what you want/need. You just may not know it yet. ;)
 

CalSgt

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Grade 8s with washers works but don’t look nice and are a far cry from an OE looking bolt. I had bought some 2.5” grade 8’s that I cut down to 2.25”, but ended up replacing them with ARP’s instead

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