After removing the coolant lines running to my throttle body and IAC valve I found it necessary to block the supply and return ports in the intake manifold. I first did this by simply securing rubber coolant caps over the steel lines, but these quickly became dry rotted and I feared they would fail. To fix this problem I simply removed the steel tubes from the ports and threaded small bolts into them. Also not shown here, my Y7 block has a 3rd port in the back in which this method could not be used. To block this port I drained the coolant system and placed 2 part high heat epoxy inside the steel tube. Before doing this make sure the inside of the tube is clean and ruffed up, I used a demel and small stone bit.

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