it's a dependable gap, a little more than the common .035" for points, and with the HEI it should never miss a beat. of course you can always try .045" but make sure your plug is capable of that gap without bending the electrode at an angle to get it. there are different plugs specifically for wider gaps, the electrodes are longer and don't need to be mis-shaped.

extended tip plugs are usually designed for the wider HEI gaps.