Titanium connecting rods for sbm 416

I think you got rod ratio mixed with weight.
When you stroke your engine you from a favourable 1.85 or 1.71 depending if starting from a 340(273/318) or 360 to 1.53:1 with a 4" which is considered on the low side.

This ratio will cause more friction (slight loss of hp) and bore wear. It was a worry that these engine would have a short life cause of this when 4" stroke first became popular. Stroking brought this worry with all makes and brands of engines. Buts been proving over time (Last decade or so) that it was a lot of worrying for nothing. Not that it doesn't have some truth to it but in practice it's of little concern.

The standard forged bottom is more than enough for what you want.