Unless the gasket material is a ceramic or asbestos material (the A3 gaskets are) then you need to shield the gasket from the exhaust heat.
Also if you block the heat riser and drive the car in under 20 degree air temperatures the carb will freeze up on an aluminum intake manifold.
The Mr.Gasket gaskets come with a square stamped steel heat passage block.
You need to tack them in place first so they don't fall out when you place the manifold on.
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