Cupped washers

70Duster340 said

I'm searching for those washers to attach the hi-po exhaust manifolds. So far, what I have found are sorta pricey, but that's not the problem currently. How many are required? I've gotten differing information, depending on where they are available. I've seen that 4 are needed, 1 on each corner. I've also seen that as many as 12 are called for.
Can anyone give me a solid number? Also, is there a good source for these. I have all the studs and sleeve bolts, just missing the cup washers.
Thanks!

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Well, you KNOW it can't be twelve, as there is no way the cup washers will fit under the sleeve nuts on the second and fifth bolts with 340 manifolds.
Some of the confusion may come from the fact that the 273/318 manifolds used washers under the four outboard bolts/studs, but those manifolds didn't use sleeve nuts. The 340 manifolds used sleeve nuts on two and five, and washers on the ends. I have never seen washers on the two center bolts from the factory, but if you do elect to use them there make sure you use slightly longer bolts in order to get full thread engagement.