Phenolic spacer
#5
I'm mainly using it to restore proper PCV operation. The situation I had without it was a vacuum leak through the IM PCV valve and also had oil getting into the intake somehow. I've already bought it and even got the special 8mm-6mm shoulder bolts for my L61. I'm going to use it one way or another. It has to help with heat soak. Aluminum is fairly conductive and as long as the temp of the IM is less than the head it will be pulling in excess heat from the engine at a significant rate. The phenolic spacer doesn't eliminate this heat transfer but should slow it significantly to the point where hopefully my IC will be functioning to cool my intake charge instead of as a 2nd engine radiator. Depending on the specific conductivity of the phenolic spacer the added resistance will result in a lower steady state temperature.
#7
But when you cut a channel into the manifold the stock metal gasket doesn't have provisions for this. If you just slot out the gasket you wouldn't get a good seal. I would think you would have to use some sort of RTV to make it work properly this way as well.
#10
I used this stuff (but in squeeze tube form) on my Exhaust to header one time. Was not fun to bust loose so I haven't used it sense. Have you ever taken off your intake manifold since you did this? The way my luck goes this won't be the last time I have to take the IM off.