318 cam suggestions

The alloy heads when combined with a tight quench,
will support very high cylinder pressure on pumpgas .
Good luck getting there with flat-tops and a 340 cam.
It will never happen. See Note-1


If you ignore the pressure possibility, the guy in the next lane with an identical set up but pushing 200psi, is gonna teach you the high-pressure lesson.
Making Power is all about the power of expanding gas pressure. All the cams in any catalog cannot make power without compression.
Each bigger cam will just extend the operating range about 200 rpm higher. So all of a sudden, 5 cams later, your power is peaking some 1000 rpm higher, say 5400rpm, but your pressures is some 40/50 psi down from where it should be with alloy heads, and so, your hiway gears are keeping you in that oh-so-modestly-powered zone to say 4000 rpm/40 mph. Don't even imagine this combo can spin two tires bigger than the 205s that may be on it; 205s if yur lucky.
But
Match your cam to your Static Compression Ratio, so as to get a Dynamic Compression Ratio in the window of 8.8 to 9.1, WITH a tight quench, with the alloy heads and you are guaranteed to have a fun car
Do it right, and it will spin tires, make tremendous torque and great fuel mileage, and it will do it all on 87E10 gas.
Do it wrong, and you'll be burning best gas, having a dog off the line, and fighting detonation.
But with the 2.73 gears; you'll have a great passing gear at 40/45 mph.
Ask me how I know.
I'll tell ya; cuz I did it twice with same results. My loss is your gain.

Note-1
That 340cam, in already 4 degrees advanced, has an ICA of 64*..
To make a 9.0 Dcr will require an Scr of 11.3. and an SCR of 11.3 requires a maximum total chamber size of about 64.3 cc.
If the pistons are down at the usual .057, that is already 11.4cc.
The .028 gaskets will not survive this pressure without special prep, so yur gonna have to use the .039 Fellpros, making your Q already .096, which is more that double of where it needs to be. But, that FellPro gasket is 8.6cc IIRC.
So far then, we are up to 20cc, so the heads are gonna need to be 44.3cc. It doesn't really matter tho, cuz there ain't no Q with is combo, so there is no sense running it.

To get the Q you need, the pistons have to be up at the tops of the bores for an .039 gasket. for a deck clearance of zero, and a Q of .039, which is already baggy. But these pistons will need some eyebrows so lets call them 5cc, and the 8.6 gasket totals 13.6cc so now, the heads can be up to 50.7cc, to run the 64*Ica.

The next smaller Ica might be 61*Ica, and it will run at 11.1 Scr, for a total of 65.6cc, and now the heads can be 52cc

Once the pistons are up at the decks with a tight Q, there is a dozen ways to skin this cat, but the 340 cam should not be one of them. I guarantee you that after the tune is in, you will not be sorry about the money you spent in zero-decking.

And like has already been said, the 2.76s gotta go sooner or later. Whereas;
IMO, if you get the pressure up to a minimum 180psi(alloy heads), the 2000 stall can stay.
But if the convertor has not yet been ordered, I would wait until you know exactly how much cylinder pressure your 318 is making. For a streeter; the more pressure it makes, the less stall she'll need .

Oh and BTW, Yes, I have run a Scr of 11.3/ Dcr of 9.2 with alloy heads, and at .028Q......... on 87E10!,
for at least 1 year and many miles.
But when that smaller cam dropped lobes in it's fourth year. I dropped some pressure on purpose and installed the next bigger cam. Down to 11.0/ Dcr of 8.8, and pressure down to 180/185..
But-um, I have a 367, and a starter gear equivalent to 4.12s, so I didn't really need all that pressure, lol. Truthfully, I really miss having 195psi, but 185 on a 367 is still too much off the line. But it pulls pretty hard at the top.

If I was building a 318,
I'd still target a zero-deck, and use the .028 gaskets, but I would use closed chamber iron heads, setting the pressure to 165>170psi. Then; if the pressure is too high, I have several detonation-fighting tools in the tool-kit, namely;
Installing a spreadbore/vacuum-secondary carb, and staging the secondaries a lil later.
and/or slowing the timing down,
and/or retarding the cam,up to 4 degrees
and/or gaskets up to .012 thicker,
and/or the next bigger cam will delay the Ica another 3 or 4 degrees.

It's way easier to engineer 165 psi for iron, than 195 for alloys.