Inputs on a home built 318 for red light to red light fun

Before you go crazy, go find your guaranteed-to-fit-a-4-speed headers, cuz for "7500 and up" you can't be running logs.
The 70 318 was a "hi-compression" engine, and with 4 series gears, for stoplight fun, in an early-A, you could actually leave the long-block totally stock.
AFAIK there are no off the shelf pistons available to run enough cylinder-pressure to support a cam for "7500 and up" ; meaning 10.5 Scr is NOT ENOUGH ratio to make enough low-rpm pressure for those times when you are just tooling around; this will force you to be down-shifting every time you have to drive over a nickel.
Consider your gearing;
With a Standard A833(2.66low), 4.88s, and 24.5" tires;
>8000rpm is 45 in first, 62 in second, 85 in third, 120 in direct.
>cruising at 32mph will be; 5700 in First/ 4100 in Second/ 3000 in Third/ 2140 in direct.
>cruising at 50mph will be; 8900 in First/ 6400 in Second/ 4700 in Third/ 3340 in Direct
>cruising at 65mph will be 4350 in Fourth.
>At WOT, with as much tire as you can fit into the stock tubs, the hi-winding 318 will likely burn right thru first gear, so guess what, 4.88s is way too much gear. Like RRR said, 3.91s is more like it, and as others have said, 8000 is probably not realistic.... because now, 8000 with 3.91s and 24.5s; top of second-gear is 78 mph.
You could pick up some bottom-end torque if you re-cam for top of Second gear = more like 65mph. That would be more like 6600 with 3.91s, and the power-peak could be an easy 400rpm less, so 6200. That's still a heckuva cam for a 318.
The 292/509 won't make it.
So at a true 10.5Scr, with a cam that is likely to be two sizes bigger than the 292, the bottom-end is still gonna be soft, possibly/probably as soft or softer, than a 2bbl 273; if that is acceptable to you, only you can decide.

Happy HotRodding