318 power?

Ottmundr said
You care enough to ask so...
Ok, I get it that you're throwing it together from stuff you already had on hand, buuuuuut....

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You spent the money to get the 318 zero decked. Square to the crank? bored/honed? Why not pick up a cheap 360 block for $100 and do those same operations, that'll give you +0.090 bore and about +1/4" stroke!
340 crank? why not sell it and get a new internally balanced 360 crank with the above block? What year was the 318 block? Are you aware that the factory did use forged cranks in 318 blocks?
What kind of KB pistons? cast? hypereuctectic? forged? weight?
what rods to go with the pistons, and was the rotating assembly balanced?
heads untouched eddys, why? why not sell the eddys and get some trick flows?
hydraulic cam with adjustable rockers? why not a solid flat tappet, you're gonna have to check the rockers anyways.
is that torque converter appropriate to that cam?

If you just wanted to get it together and on the road this weekend, I get it. Your thinking and my thinking is very different when it comes to building something because I am very VERY lazy, and I only want to do it once.

Measure twice, cut once. Sure, it's more work up front, that leads to less work on the back end. And I LIKE up front.

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Wellll, parts he already has in the shop/garage. Nothing wrong with that. Sell stuff off and purcase replacement? Not exactly wise unless selling a collector item for big $. Only a 318? That is only 22 cubes smaller than a 340. So if you are looking at the power/cube and about 400HP, the difference should be about 30HP. Now the 340's larger bore unshrouds the intake more over the 318 which should provide a bit of a benefit. That said the valve size and combustion chamber are the biggest concern.
Now the cylinder displacement and expected 2.02 intake valve size indicates the LSA should be 106°. If the 108° cam is on a shelf, I would use it as it will be much better than the catalogue 110° and 112° cams marketed and "popular" today. Early electronic carbs with an O2 sensor and throttle body injection were sensitive to overlap, dictating wider LSA to keep raw fuel out of the exhaust. With modern injection and tuning or plain carb intake, the narrower LSA will provide better total performance. Yes, idle will be rougher and low speed torque may be down a bit. The driving package or combination is the consideration and end result.
To the OP, toss it together with the parts you have.
To the poster yipping about balancing, do not get me wrong, I do encourage balancing an assembly. Let me relate a story though. Years ago some younger guys were into racing Mopars. They would scrounge for big cams of the day and gears. They were turning what I consider crazy RPMs on unbalanced short blocks. Finally one came into the service station I worked at and told me he had purchased a balanced short block as I had been recommending. That lasted 1 week to the first missed shift and the block got aired out. No more talk of balancing allowed due to the extra cost. They still vented blocks but saved the balancing costs. Without missing shifts a balanced rotating assembly should run smoother and longer. With the balance, a cc to bring combustion chambers to the same volume will aid smooth running as well.