On a 1946 Chevrolet 216, what is the HEX BOLT SIZE/LENGTH of the SIX BOLTS that bolt both the exhaust manifold and intake manifold into the HEAD. Both SAE and METRIC information is appreciated. Planning on using Grade 8 or higher.
Good luck with the Grade 8 bolts. You'll strip the threads in the cylinder head before you get enough torque on them to keep them from loosening up and falling out. GM used Grade 5 in those locations. As soon as it gets daylight in the morning I'll be glad to measure some bolt length for you on several of the engines I've got stockpiled. Jerry
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2-3/4" bottom of cap to end of bolt (1949 - newer) 1-11/16" unthreaded shoulder I don't have a 1948 and earlier engine so hopefully someone else can provide the length.
1-3/8" bottom of cap to end of bolt 1/4" unthreaded shoulder
1-3/8" bottom of cap to end of bolt 1/4" unthreaded shoulder
Last edited by buoymaker; 05/24/20223:31 PM.
"Adding CFM to a truck will only help at engine speeds you don't want to use." "I found there was nothing to gain beyond 400 CFM."
Might as well include the "Cons" along with the "Pros'. Studs instead of bolts, in the head, stick out and can be broken by accident. A real pain if broken flush. I don't know if a machine shop would have to remove the studs for head resurfacing. However, studs would be easier for manifold installation. Choose your poison I guess.
"Adding CFM to a truck will only help at engine speeds you don't want to use." "I found there was nothing to gain beyond 400 CFM."
Darling Now you know the manifolds have to grow a little when heated so not a real high torque setting,also have to shrink when cooling. It's why the pin holes are a little big.