Lets build a CHEAP(!!!!!!!) bracket motor!

All good Rumble. Dang, I wish I investigated more into the magnums before spending so much on a 340. This one happens to be quite done up and does have stage 1 edelbrock heads which was a surprise to me because I thought the big valved 340 heads were really good but you mentioned the flow issue, and that's probably why the guy who built this replaced those heads.
IMO, for the OE equipment, the MoPar cylinder head isn’t horrible. It is just a stock passenger head on a performance mill. (AKA 340) And there is the limitation, as delivered. Some of the 340 heads flow quite well for there intended purpose of the day. The better heads will clock in around the 220 cfm area. Anyone reading this feel free to correct me if they have actual flow numbers or there 340 head. It’s all good there!

Before the Edelbrock head was introduced, you ether ported your iron or went to Ma’MoPar and grabbed better iron. (W2’s) This was nearly the only route for a better head for a while.

Member @yellow rose often said/says (and ever so correctly!) that making HP (and winning the race) is a function of rpm in the form of as many (rpm) as you can get in quicker. The shorter stroke can produce more cycles of power making explosions than a longer stroke engine can. It is a matter of distance the piston travels. This has been known for a very long time. This method is what the Europeans have employed in there race cars since nearly the dawn of automotive racing.

Now combine the 340’s shorter stroke with a higher flowing cylinder head and, well, LOL, your half way there. The rest is a two part duet dance between a fast acting high valve rising cam correctly cut & timed for the intended purpose with free breathing in and out.

On a race track, this is a good and normal way to do it. The flip side is huge torque and a low gear ratio to have the engine pull the car through. This is the (Well, IMO) best way to do it on the street. Torque is major fun here. And your friend on your street, street strip car.

The 340 is the top OE SB HP maker dog.
The 360/Magnum is the next best bet. And from where I stand, it is really the best bang for the buck for the street based car on that most people will desire more torque for an easier time moving there car down the street because a street car is heavier. More than likely with all the goodies we love to have. PS, PB, AC, stereo, best & defrost, spare tires and tools for a trip, etc.... the list goes on & on for the things a strip or a seriously heavy duty street strip car will not have. And when you think about it, that is a whole lot of weight. The enemy of a quick low ET/high MPH car.

I like that CL 5.9. Just like what I pirated from my daughters wrecked 80K Durango, same year.

Now how heavy is your future 340 car?
(Answer really not required)