New coil question

I have no experience with them. Modern "E" core coils are typically (I think) all epoxy. Oil was used for HV insulation and heat conductivity. I have no idea what the heat conductivity or insulation of silicone is Might be better, might not

The disadvantage to oil is that "some" coils if mounted in certain ways, "alleged" can expose the windings above the oil level, but in the day Mopars were mounted both vertically and horizontally, as were Fords. So who knows?

Of course oil can leak........