Sorry for the delay, I was just waiting until I was at a real computer so I could avoid quoting a huge block of text
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My recommendation to start is to purchase a few books that will provide the knowledge you can use to put into place the best plan in building an engine close to what you want to get the performance you are looking for. ......
This is a good point, and it's one I've followed. However, everything out there is geared either for a plain, stock rebuild, or a performance build in a car weighing 3500 lb. When people say they're building a "torque monster" if you look at the results, they have power peaks well past 5500 RPM, where I don't think many of us are going. In my case, that left me posting a bunch of weird queries here and trying to piece together information on how to maximize performance in the 1000-5000 RPM range.
The books are good, but they're mostly good because they talk about the systems, and you have to figure out your own system after them.
.... You want to select an RPM range that your cam will work best in and provide good vacuum to operate the power brakes if you have them. NO cam works in all RPM ranges - its a trade off. You may give up low RPM's for mid-to-upper RPM's. You may want to give up upper RPM's for mid-to-lower RPM's. If most of your driving will be in the mid-to-lower RPM's, why would you give that up just to be able to occasionally make a blast to 6,000 RPM's? And if you build the engine and it only spins 5,000 RPM's, do you really need to spend extra dollars on forged rods, pistons, or even a roller cam?
Yes, cams work in a certain range, but I disagree with the conclusion that a roller cam is therefore wasted. A roller cam allows for faster ramp rates, which will improve cylinder filling at any RPM. If you open the valves far and fast with short duration, you're going to get improved torque at low speeds. That's what that Hot Rod article was showing. Unfortunately, it was a 383 and still peaked at 5600 rpm.
As you go to bigger cubes, the same duration will move the RPM for the power/torque peaks down with the same cam. So would the cam listed in the article have peak power 600-800 rpm lower? I don't know, and I don't know how to calculate that. My rule of thumb from talking to cam companies, reading, and thinking says that I should keep the 0.050" duration at or below 220 degrees. I'd love to have some feedback on this opinion.
When selecting a head or doing port work, keep in mind that an engine responds to port velocity. Add bigger flowing heads to feed the bigger cubes and you may find that it is slow to respond at lower RPM's and only picks up at higher RPM's - this is why you would want a higher stall converter or better gearing.
Disagree here, too. If you go from 440 to 500 inches, you're not going to be bogging off the bottom with 440-source heads, stock Eddy heads, or mildly ported irons. We're not talking Max Wedge ports here.
Again, I am sure I am going to get an ear full from all the professionals on this, but a good build really has to be thought out and through before you pull the trigger on a single part. I am not one who has deep pockets, so I want my best value for my buck and I want a build that puts a smile on my face when I control that gas pedal in the down position. Knowledge is power and reading all you can and learning the engine and your options will save you from having to consume a couple bottles of aspirin and antacid during your build.
No, the experts probably agree with you, and it's only the amateurs like me who disagree.
Like you, I don't have deep pockets. I only have the money to rebuild my engine, trans, rear end, driveshaft, and upgrade like $2k in performance extras. I can do it with good parts, and I can do it well, but I can only do it once. As a result, I've spent a lot of time trying to figure out how to build something right that isn't in the middle of the whole performance industry's focus. I'm not there yet, but I think I've made some progress. I chime in on all of these threads because I hope to get feedback on my ideas, so I can refine them. Don't take my comments negatively, please. I always love reading your posts.
