Thoughts on a 390 cu in. stroker from a 318?

I’m pretty sure you know I’m not anti 318, but to me we’re not talking about 318’s a 390 isn’t a 318 anymore, your stated goal was low end torque aka displacement, to me we’re talking 365 vs 390 vs 408, a 365 can make decent low end but if more is needed/wanted than a 390 gonna make about 30 tq more and for similar price 408 will make 50 tq more than a 365, obviously there could be other factors but for the dollar per lbs-ft the 408 would be the wiser move. But if you chose 390 or even a 323 that’s up to you and I’ll try my best to help with whatever choice is made.
I don't think that the hp or torque increase just based on displacement increase alone is accurate. If we're talking same EVERYTHING else between one CID and another.. carb intake cam heads ignition EVERYTHING then maybe... But stroke it then that means bigger cam, different carb, may head work you wouldn't have "wasted time on" on a stocker and that's all out the window