New to Me 1968

The only way to get 340 cubes out of a teener at 3.94 bore is to use a 3.48 stroke.
For reference;
My Zero-deck 360, with alloy heads, and running the pressure up into the zone of 185>195 psi, makes more torque than my 68 Barracuda chassis can handle, but
it will burn 87E10, at full-timing, even at 205*F.
I see no problem building a teener using the same plan. It will just require a lil more rear gear than 3.23s to be as explosive as my 360 is with 3.23s.
However;
If I was to build a 318, for a streeter;
I wouldn't spend a lotta money on the engine.
Instead I would install a 4-speed auto with Overdrive and some Hi-Po rear gears, whatever it takes to get:
a starter-gear in the window of 10>11, to 1; and
an overdrive ratio that gets the cruise rpm down to in the window of 2000>2400, depending on the cam, and the cruising speed.
This combo is easy to do with a Chevy200R4, and say 3.91 rear gears.. That's gonna be a hard combo to beat even with a hi-po 318, a regular TF, and 3.23s. Actually, the Hi-Po won't touch it below 65 mph, with 3.23s.
As to Roadgears;
The Torque-Flite ratios, with 3.23s are;
7.91-4.68-3.23; versus the 200R4 with 3.91s, are
10.87-6.14-3.91-2.62 and maybe it comes with a loc-up.
> A Final-Drive of 2.62 will cruise at ~65=2100/75= 2450 (with 27"tires), in loc-up.
>The 10.87 starter-gear will take off like the engine just picked up 37% more torque, making your teener feel like a BB ....... in first gear, lol.
> add a lil stall to the game, and you got a tire-frying Teener, maybe even deep into Second gear.
> the Road-gear of 6.14 is like running a A904 with 4.23s, so yeah my smogger winter-motor roasted Second with 4.30s. But 65@ 3500 was a beotch. The 4.30s were only in there maybe a week, a leftover of the Summer combo.

I'm just trying to be helpful, and maybe save you some money. I have no hidden agenda.
Some say I hate Teeners, but that is just not true!
What I dislike/not even hate, is the combo of a 7.5Compression ratio Teener wearing X-heads, with a stock stall convertor, in a 3600 pound car, pulling hiway gears. That is just (insert your own adjective here). And yet, newbe's do it all the time....................

Sorry about your Health Situation.
Onwards and upwards.
Happy HotRodding.