55fordf100,
What size is your y block and what exhaust are you running? I have a holley 350 two barrel on my 272 and it is plenty of carb for that engine. I'd argue that a two barrel 350 is all you need for a 292 most people get better performance from a 390, 450, 495 four barrel as the primaries are smaller and provide a crisp throttle. A larger carb will not be advantageous as the engine/exhaust will not flow more than about 90% volumetric efficiency. Do the math.
E plugs are probably snake oil. Most exotic metal cored multi tipped spark plugs are. Most of these variables have been tried several times. There is a reason that spark plugs are the same as they were 100 years ago when they were invented.
If you have an original 55 y block and it's still running vacuum only advance and a 94. It's a really good project to change to a Modern carb on a later manifold and a dizzy with both mechanical and vacuum advance and dual exhaust. This makes the y crisp and energetic and surprisingly good in the configuration.
Cheers
Warren
Grizzly (Aussie Mainline)