318>390 Stroker.......Your thoughts

More thoughts;
Low 12s with SuperStock suspension is 377hp@3300pounds.
With street suspension, expect at least a half a second slower, so 12.5s; is that low 12s enough for you?
The trapspeed associated with that ET, is about 112mph, which direct gear with an automatic, will require, at 10% slip, a rear gear of 4.30s; for 112=6300; which is with 88" rollout tires =28s.
6300 thru the traps will require the powerpeak to be around 6000
at 390 cubes, that will require a heckuva cam, too much for street I think.
4.10 would make it 6000 and a powerpeak at around 5700, but the tires will need to be bigger, say 90" that's still a pretty big for street cam. 90inches is a 28.65 tire, rounds to 29", for 112=5322@zero-slip, perhaps 5850 on the tach @10% slip, and a powerpeak at say 5500. That's doable on the street, with a cam around [email protected] in the 390.
The 250* cam would require a lot of cylinder pressure in the 390, to not be sluggish at low-rpm, so yur probably looking at the usual, hi-stall bandaid. And, of course, those 4.10s are Not gonna be hiway friendly. Well, that 292 cam is none too street friendly, either
Of course the whole thing depends on a raceweight of 3300#. Allowing 200 for the dressed driver, that makes for a car weight of 3100........ which is a bit of problem, if you want to keep it as a streeter.

So then, perhaps a review of your application is in order.

Obviously, the engine has to stay.
From your avatar, Ima guessing you have an early 70s Dart at 111wb or hopefully a 2dr Scamp @108wb. Those Scamps come in at around 3100 without power steering, so that is why I used 3100. And that has to stay.
The 4.10s kindof have to stay.
and the hi-stall has to stay.
But to make it streetable, yur gonna need a modest stall and an overdrive, and I don't know about you but I'll never run a 250* cam again on the street; been there/done that.
So that just leaves the transmission.
If the auto has to stay, then I would make it an A500 lock-up.
With it's slightly lower gear ratios, this would allow a lesser stall, and the 4.10s become 2.83s in .69overdrive.
And finally, I would swap out that theoretical 292hydro-cam for a solid lifter with say 228*@.050 after lashing.
Of course the power will be down some, so the MPH will drop. Say she comes in at 106mph; that is a requirement of 303hp, which is cake for the 390. But the ET has fallen to 12.9. Is that enough for you?
Since the mph has fallen to 106, you might think that you no longer require the 4.10s. But that is not correct. Your power-peak has fallen about the same percentage as the speed, namely 5%, so the rear gear also has to stay.

Ok now, This is NOT a recipe of what AJ thinks you should do.
This is just a study of what you might expect your future to look like when you try to marry a "street car" to a "race car". In this endeavor, you really need a big tame engine and or a lightweight chassis. ell, 390 is already pretty big.

You mentioned that you would prefer torque over power. That is a wise choice. But on the street, getting a street tire that fits in the factory tubs, to stick, with anything over a 318 engine is already a challenge. The point is that it is easy, with anything bigger than say a small-cam 340, to blow the tires off, with just about any rear street-gear. So when you show up, with a hi-stall 390 and 4.10s, the tires don't stand a chance. Your Scamp is not an 80,000 pound Kenworth,lol; it will be all too easy to have too much torque, and you just can never hit the go-pedal at full power, in that configuration.
So what's the answer?
IDK
I thought I knew.
I had a hi-pressure 367 with a 223/230/110 cam, but with a clutch, and the 3650 pound raceweight street-car has 3.55s, and she went [email protected] right out of the gate with no tuning; spinning thru two gears and part of the third, with street tires. That's nuts. I installed a double overdrive in it, which took the 3.55s down to 1.97; and 65 was 1600rpm. And I took the 750DP off it and installed a lean-calibrated 600VS on it with the Secondaries disconnected. I installed a dash-mounted, dial-back, timing module, so I could give the engine the timing it wanted.
On a certain day-trip, in 2004, she returned 32 mpgs.
For it's trapspeed and raceweight, the Wallace Calculator predicted 330horsepower. but the torque at 195psi CCP was outrageous. I didn't care that it was "slow", cuz it was just so much fun.
That cam died, so I replaced it with the next bigger cam (230/237/110) from the same supplier. Simultaneously I reduced the pressure to 180psi. This combo, in the Eighth, went 93mph @7.92 @3457 raceweight, translating to over 400hp, which translates to an unverified 11.98@115mph/SS suspension/in the quarter.
But the low-speed/low rpm torque fell off quite a bit, and the fuel economy went away. No big deal, the car has a clutch, right? lol.
So IDK anymore.
Your 390 is 6% bigger than my 367 and at 3300pounds your car would be 10% lighter than mine, at 3650 in street trim.
But you know, I have a GVod, which I often use as a splitter. The day I went to the 1/8th track, I was at 3457pounds, and I used 4 gear ratios, to hit that number. The road-gears were 10.97-8.56-6.82-5.32; and 93 was 6160 on a powerpeak somewhere between 5100 and 5300, with that 230* cam. BTW; That 5.32 is Second-over.
So then, these are my thoughts, maybe you can take away something from them.
I liked the 223* cam way better.