350 guy here.
I've done a couple of iterations on 350 motors.
The first iteration was a very basic 69 350, #47 heads. This was the 1969 equivalent of your 1970 350. I put a Summit 2800 cam in it, with 4 barrel intake. I ran both Qjets and Holley carbs on it. The Qjet was a better all around carb, but Holleys were simpler, and did fine too when that is what I had. I ran an HEI ignition, with dual exhaust. This was a very basic, fun street cruising combo that did not require any exotic build elements or parts. The 2800 cam works great with stock valve train parts. It is similar to the previously suggested 067 cam. This was all in a 67 Firebird with 3 speed auto and 3.23 mid level performance street gears. In retrospect, it was a wonderful blend of cost effectiveness, simple tech, performance, and drivability. It broke just under 15's in the quarter when I decided to chase after more power and performance in iteration number two...
Iteration two is a 350 with forged parts (planned on doing a turbo build that never happened), and Ram Air big valve #12 heads. This was a compression bump, which gave more power, but kept it pump gas capable. I run a Lunati 702 Voodoo cam, HEI, headers, 3.73 gears, and a 2000 stall converter. This cam required careful selection and upgrade of valve train and head parts, because too much lift with big valves on a 350 WILL cause valves to contact the cylinder. I also run a FiTech system, because I wanted to play with some modern style fuel delivery. All of this cost significant money, and made the car less street friendly (3600-ish rpm on the highway).
Here in the Phoenix area there is only one drag strip in town, and every time I went I would have to take a day of vacation, lose sleep, and spend a good $100+ just to get one, maybe two runs down the track in a night. Most of that time was spent pretending I was part of a cool drag race culture while the track spent an hour cleaning up somebody's oily breakdown, pretending they cared.
Not my thing anymore.
I'm not going to undo what I built engine-wise, because it is no doubt a blast to drive. But what I will do is go back to a simpler time, with better street gears and street manners. I will go with a quieter exhaust, and stop making life goals of burning down the Dairy Queen parking lot while pretending "Street Outlaws" has ANYTHING to do with me.
Make your car reliable. Make it affordable. Make it fun but not crazy. Enjoy the time with your dad. Get a stereo in it with bluetooth, and tell dad to throw on his playlist that probably had a lot of spandex and hairspray involved. See how many different hamburger places you can visit in one summer, and how many burnout strips you can leave on that one almost deserted road that everybody has nearby.
To put it in very simple terms, I have now arrived at a point where I lean more toward "Roadkill" or "Vice Grip Garage". It saves money and sanity.
4 barrel intake and carb? Yes.
HEI ignition? Yes.
Headers and reasonable exhaust that doesn't make you an enemy of the state? Yes.
Good wiring that doesn't catch on fire? Yes.
Brakes that can stop you? Yes. Front disc/rear drum are fine.
Seat belts, preferably 3 point? Yes. After breaking my neck in a car with air bags and 3 point belts, I am a fan of some reasonable safety gear.
Cam swap to something like the 067 or 2800? I like it. Best time to do this is when the intake is off.
Changing rear gears or adding a limited slip differential? This is not a lightweight diy project. Best saved for later as money and/or skill develops.
Wow. I've turned into such a "square".
