The best way to do both,
> is to assist the engine in processing air.
>This begins with a solid foundation, and don't let anyone tell you different, this means a having a decently high cranking compression number.
> it's ALL, I say ALL
about getting as much air into and thru the engine, as is possible, which includes keeping that air dense, on it's way into the chambers.
On a street engine, you have the unfortunate problem of making whatever monster you build, work within the confines of the rest of the combo. And, unfortunately, the engine has to be throttled some 95 or more percent of the time; which brings the difficulty of carburetion into play..
So then,
to optimize for street,
the first decision you have to make is; What fuel will you be using. If best fuel available is just 91, then that is your first handicap.
If that fuel is to rich for your blood, then that is your second handicap.
If then your DD project becomes a weekend warrior, that's a new handicap.
If the chassis will not accept decently sized tires, there's another handicap.
If the vehicle in question weigh over two tons, there's another.
If it is stuck with a low-stall convertor, and hiway gears, those might have to be replaced.
And if you are at altitude, that could kill the 318 altogether.
It's easy to get carried away with designing a hi-powered 318, only to find that your dream car will never run with it until everything behind it is upgraded, and the car still only does one thing right, and it's not what you had expected.
If you don't already have a car, I highly recommend to not start building a 318. If you all of a sudden can't find a relatively lightweight A-body in your budget, and end up with a 4000pound behemoth, then you may need a bigger engine.
Your guide for acceptable performance is 10 cubes per 100 pounds of ready to run chassis, you not in it. So then, at 4000 pounds, you will need a 400 cuber. Whereas the 318 is good at around 3200, and a 360 for 3600 pounds.
Operating outside these guidelines will be either disappointing or expensive.
So I mean, if you find a beautiful 71 Polara in your price range, she's gonna need a 360 or more. and trying to find a lightweight A in rebuildable condition, is as good as impossible but if you do, well then, mortgage the house.
Building the 318 from scratch to meet your goals is doable, if not cheep. Whereas fitting it into a winning combo, make take some ingenuity. It's just way easier with a bigger engine.
And no, I'm not knocking the 318. You can fit it into almost any combo with higher stall than stock convertor, and/or gearing, and the overdrive auto is a fabulous solution.
If you can commit to one of those, then the 318 becomes much more attractive.
If you want to discuss ideas away from the naysayers, you can PM me.