Someone told me that you could drill out and enlarge the intake opening on the nose cone of the IMCO SC lower to improve water pick up. Is this correct and has anyone done it.

Most that go from a bavo lower to an SC complain about to much pressure ? not sure why you'd need to drill it bigger

Does too much pressure affect your temp? I don’t have a water pressure gauge on my cluster and the scan tool I have doesn’t give water pressure.

Temps dont think so, Im running SC lowers feeding two stage pumps and I have plenty of water flow,

I recommend getting a water pressure gauge hooked up. Too much pressure can blow intake gaskets. 30psi at WOT is about the max you want.

1. You need a water pressure gauge. It will show that something is wrong way before you see it on the temp gauge. Good investment.
2. Water pressure is useful as a proxy for water flow, but not on its own. It will vary from engine to engine. E.g. on many outboard engines, 10 psi at WOT is sketchy. On the other hand, the day before yesterday, my friend's 540/Bravo combo never showed more than single digit water pressure, but temperatures stayed in line.
3. From a cooling perspective, there is no such thing as too much water pressure, only not enough water pressure. However, as Griff pointed out, on inboards, there might be other considerations than cooling.

I’ll install a guage.