Quote Originally Posted by Farrar View Post
Well, the Dodge Monaco O-rings are a perfect fit (of course) but I still have a vacuum leak at cylinder #4.
Digging back to this picture, the intake manifold appears to have slotted bolt holes and port spacing that's just a tad off. I wouldn't be surprised if it drifts around after several heat/cool cycles.

If you can manipulate the manifold into a position that is leak-free at all ports you may want to consider something like nord lock washers on the manifold mounting bolts. I use nord locks on my crank position sensor and I swear you could lift the car by the sensor and it wouldn't move.

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