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Old 07-05-2015, 09:49 PM
Three Peaks Three Peaks is offline
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Location: Hillsboro, OR
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I use the same method as David, but I usually use RTV. If I have a really tough situation, like a corner that may not be fitting absolutely perfectly, I put RTV on both sides of the gasket and spread thin with my fingers before dropping it over the guide bolts, then slide on the manifold and tighten down as above.
Be sure to tighten down your manifold in stages. Most SBF manifold bolts need to be tightened to around 18-20 ft/lbs for proper torque, if I remember correctly. Tighten in sequence the first time to around 10-12, then step up half way to 12-14, then wait about 10 minutes for the gaskets to "relax" then tighten to the final torque spec. I've found several times over the years that if I wait an hour or more, the manifold will require another retorque even if not started or driven. I've always thought it was because the gasket was compressing (or what I call relaxing) over time and in a little while it will compress as much as it is going to and you can torque it for the final time. This has never failed me over many years of dealing with this issue. It was taught to me by a friend of my father who built race engines.

Bob
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