Closer LSA will give you more bottom end, wider will help make them idle smoother with more intake manifold vacuum at idle, if that is what you want.
Does your car have power brakes? If so that is a concern also
The last six pack street pump gas motor I built for myself had a solid roller cam with 260 degrees duration at .050 intake valve lift with .420 lobe lift, the exhausts lobe had 266 degrees @ .050 with .409 lobe lift. I ended up switching the rocker arms from the 1.5 ratio to 1.6 ratio Harland Sharp aluminum roller rocker set up
I built that motor, 505 C.I. 400 blocs, to race on the streets in Los Angles, which I didn't get to do before getting that car finished
It was fats, 9.993 ET at 134.8 MPH in the 1/4 mile corked up with full 3.0 inch exhaust system on it exiting at the rear bumper
Are you using stock vacuum carbs or after market mechanicals?
If using stock type vacuum carbs use the outer carbs idle mixture screws in the base plates to help get the idle fuel mixtures set for the best idle, all the stock ones I've work on like from 1/4 to 1/3 a turn out from gently bottomed
I would use the center carb for the final fine tuning and setting the idle speed
IHTHs