72 340 build vs...other options

On the street, with an A-body, not racing;
you do not need 2.02s
you do not need a long stroke
You do not need forged parts
Any top end will fit on any bottom end.
Allowing for cylinder-pressure adjustments;
A 318 with a cam one size bigger than a 340, will about match it for absolute-power, ie NOT torque
A 318 with max compression will match the bottom end torque of a stock lo compression 360.
A lo-compression 340 with a 318-cam will about match the 318 for fuel economy but have more bottom end.
The 340 burble was more from the rectangular tips and high-energy exhaust. The 44* of overlap is actually very modest.
For the street, I don't think much of the 340 cam and I have several of them packed away.
A 318 will happily rev to whatever a 340 can, and so will a 360. All any of them need is the right springs and lifters, plus the standard oiling mods.
KB107 pistons for the 360 are about 2/3rd the weight of the 340 forged slugs. After balancing, the 360 crank will go to 7200 as often as you like for more than 125,000 miles (mine)
A 360 can happily pull 65=1600 rpm (mine) all day every day. Try that with your 430 hp-340.
What a 340 can do with a 4-gear manual, a 360 can sacrifice one gear, and the 318 will like an extra gear. Or looked at another way, whatever the 360 likes each smaller engine will like 10% more rear gear.
If a city car; second gear will make or break your combo.
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As to second gear.
I have a manual trans with a GVod behind it, so I can run any street gear I want to, and I have run everything from 2.76 to 4.30 except I never had a 3.73. And for me, having the right amount of power in second gear, at any speed it will do, is everything. In my combo, I finally settled on 3.55s. and first gear is a 3.09, The only other gear I care about is overdrive, because I live an average of 15/20 miles from civilization, so every trip I make is 90% hiway. ..... and now, 65=2240rpm.
so that 3.09 gear tops out at 44mph@6000, and on the shift, the Rs drop to 3730, and that gear will hit the power peak at about 62 mph. And I'll stretch it out to 65 and stuff her into overdrive. Done.
So then Second gear is my go-to gear. Which means I need a chitload of torque at 44mph=3730 rpm.
A stock 318 is way past it's modest torque peak, and will not cut it.
a stock 340 @3730 is a almost to it's torque peak, but that peak is more like a speed bump, it's just not enough to thrill me.
But the stock 360 is right in the thick of it's peak torque. (No, mine is not stock)
And that is why the 360 was my choice; cuz it can and did put down more torque at any speed below 55mph with 3.55s than the chassis can handle, and the smiles just keep on coming.
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BTW
Let's say my 360 makes 380ftlbs at 3730; that's 270hp.
Getting a 340 to 270hp @ 3730, is gonna be a real adventure, and with a 318, it's never gonna happen

But you say, 380 @3730 for a 360 is impossible.
Meh, you're probably right, so I bored my 360 to 4.04 and now it's a stroked 340, measuring 367 cubes, and everybody knows 340s can out-pull anything so a stroked one should pull even harder....... lol..

The truth is it doesn't matter how much torque the 360 makes at 3730, the fact is that neither of the other two are gonna touch it, build for build. Which means, they will need more gear to match it, but that changes the operating rpm! There is only one gear combo that can hit 3730 at 44 mph, which is 6.8075. It's just simple math. and 1.92 x 3.55= 6.816, daymn close.

Sometimes, most times, the choice comes down NOT to preference, but to the application, and it's intended usage. My intent is to wear out tires and have maximum fun doing it.
If my intent was maximum mpgs, I would have built a 273.
If my intent had been to appeal to the car-show fans, I wouldda built a 340.
If my intent had been to drive a bazzilion trouble-free miles, well then, a 318 mightbin on my radar.
I mean I have a shed full of blocks to chose from.
How many 340s do you want me to ship.