I'm making a throttle body flange and it may seem dumb but I'm trying to figure out a good thread to use for the bolts. I know some threads are meant for certain situations so I'm hesitant to just pick one. The holes through the TB are roughly 0.270" so I initially was thinking 1/4" - 20 thread but that seems maybe a little coarse. The flange is 1/2" thick aluminum. Anyone have any thoughts?
They're probably sized for an M6 bolt, not 1/4". Just about every fastener I've seen for that type of thing is coarse thread.
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