Advise wanted on reviving a 318

-I have done it both ways,a couple of times.
-Bigport openC heads onto stock LC 318 = soft bottom end,esp with an A/T.Smallport openC heads onto 340/360 = Dynomite bottom end, esp on 340. I attribute the results to the c/r change and port velocity.
-The worst combo was 69X-heads onto 73-318 into 71 Monaco,with 340 cam; all oem parts. No amount of tuning could get that beast off the line. But passing gear was a blast.I later figured the c/r was around 7:1
-The funnest was a complete 318-2bbl top end on to 69-340, into 65 Valiant wagon.
-Those bigport smog chambers are pretty big on a 318, esp when the 318 pistons are down in the hole.The c/r falls into the basement, along with efficiency.That, coupled to a typical oem convertor, and highway gears is a disaster for performance.
-The cure for your diss-appointment is not that far away.A little compression change goes a long way.And is likely the all-round best answer.Big gears and hi-stalls have their place, but with low compression, will keep costing you dollars forever.Whereas the compression change and a tune will bring the bottom end up to an acceptable level, and will save you money at the pump. Later a modest change in either gears or stall will perk it right up.
-The smallport heads may not be your enemy.They can work really well up to 4500rpm or so, and where is most of your driving done?If you get the c/r up, you can run either heads. A good place to target is flat-tops and a zero deck. Then.... if you can find them, an old set of closed chamber smallport heads.You could probably get close to 11:1 with those. Unfortunately, those smallport heads become a problem in the higher rpms.
-The bigport heads @ zero deck will get you close to 8.5c/r. A 65cc head and zero deck gets you near 10:1
-A closed chamber has the advantage of quench, which if used correctly, can allow a bit higher c/r before detonation arises and can get you better fuel mileage.
-So all this mumbo-jumbo boils down to is this: Focus your needs and desires, then build accordingly.Street use demands the widest parameters and the most careful co-ordination of parts.
-I believe that for most of us,the flat-top/zero deck engine is the most versatile street base,then careful co-ordination of c/r, through head and camshaft selection to achieve a dynamic c/r for your available fuel, that still allows a normal engine running temp, and full advance without detonating.
-Some will say, and others have proved that c/r is not the be-all/end-all.Well I think that needs a qualifier. A 7/1 318, NA, is a slug. And a 13/1 street motor is hardly a street motor. So the qualifier, for most of us with limited pocketbooks,is this;get the c/r to 10:1,+/- 1.0. The bigger the cam the higher the c/r and vice-versa.Then make it work with Dynamic c/r manipulation. The dynamic is far more important than some think. The Static or computed c/r is just the way to build the motor to achieve the Dynamic.Dc/r calculators can be found on-line.With a small engine like the 318 a guy really needs to focus his expectations.
-I know this is a long reply, and I truly hope you are able to make use of it.
EDIT
When I say compression falls into the basement,check out this math; the formula is c/r= (CV+cv)/cv where CV is cylinder swept volume, and cv is the total chamber volume. A stock bore 318 has a swept of 651.4cc. with an open chamber bigport head of 70cc, a gasket of about 8.4cc, pistons down in the hole .137 thats 27cc and no eyebrows, this is how it looks;
c/r= (651.4+70+8.4+27)/(70+8.4+27)= (651.4+105.4)/105.4= 7.176. Thats in the basement, and that right there is the problem. Now if you bring the deck up to zero and lose those 27cc and maybe pick up a pair of 5cc eyebrows the cv falls to 83.4cc. doing the math the new c/r comes to 8.81. thats a 23% improvement. Couple that with an early closing intake to pull up the dynamic, and then you will have something. Unfortunately, you will be married to it, because as soon as you put in a bigger cam, the low end goes soft. The only cures are gears or stall. Neither of which are long-term solutions in a daily driver.
The real cure is more cubes. A 360 has a swept of 737cc and with pistons down at .100, and with the same gasket and head, c/r comes to 8.44. So with no machining at all, you are only down .37 point,as compared to a machined and rebuilt 318. Now the fun starts. Say you put some new flat tops in that 360, at zero deck. So all youre doing is boring .030
Swept is now748.3, and again with all same parts totalling78.4, the c/r builds to 10.54. Now you can use all your current top end parts including the cam kit. Or you can swap out the cam to one in the 230* to 240* and the extra 41.8 cubes will help keep your low end from going soft. A cam in the 220* will get you a ton of torque, at 10.5c/r. With a 904 you can run almost any gear/TC. Now you can leave the engine alone, and play with gears and stall as funds are available. I can guarantee with a 10.5c/r 360, with a 223* cam, in an A-body, with a good tune it will do every thing you want it to as per post#1. I built one like that. It went 106 in the quarter,fried the 275/50s, cruised at 2200, and I could lean it out to get 36mpgUS.It did it all without overheating or breaking down, and with full timing using 87 octane E-10.
So how much will it cost? Thats not a fair question. The better question is how much more will it cost than to bring the 318 up.Well; the 318 will need pistons,decking,hot-tanking, and a cam swap. The 360 will need pistons and hot-tanking, and maybe no decking and reuse your cam. The net difference is the cost of the core LESS the cost of a cam kit; so almost nothing! Well almost. The 360 might need a few things that the 318 cannot donate, such as main bearings, oil pump,etc.
Thing is for very little MORE money you get WAY more bang. And the future mods are already planned for with the basic short block. Sorry for the long rant. Happy decisioning.