Edelbrock sells their kits by power level. They have five levels that goes from stone stock replacing the stock cast iron heads with aluminum ones just for the bling, to all out race (though I doubt if you will often win a race without some head work). Edelbrock is the source for all of Chevrolet's aluminum heads for the SBC and the BBC as sold in their GMPP catalog, though they generally add bigger valves to what Edelbrock offered.
You can examine the table that contains the five levels here:
Just bear in mind there is no free lunch. As horsepower levels climb you are taking away the ability to drive the car on the street. You don't see stock cars competing in Top Fuel, nor Top Fuel cars driven on the street for a reason.
Torker II is about as high as you can go (one horse per cubic inch of displacement) with a stock torque converter, to get to the RPM Air Gap stage you would need at least the torque converter out of a Corvette. Though you could hit 350 horsepower with that package and new flat top pistons.
Since that would be beyond your experience level I would recommend buying a complete new crate motor from Chevrolet (GMPP), and pulling and saving your stock motor for a future owner. You can buy a 350 horse 350 or a higher torque and horsepower 383 and bolt it in place of your motor (except when I looked I discovered that GM no longer sells a 383 motor) selling a ZZ4 350 in t's place since they both make the same power levels.
A cheaper though hundred horse less in power is the stone stock brand new 350 pulled off the assembly line that costs only one third of the ZZ4
When you buy a new motor from Chevy you get a GM factory warranty with it, so Chevy fixes any motor problems just like they do with a new car. That is not how the rest of the crate motors you buy work. With those engines you take it a shop that employs ASE techs to pay for the repair and then file an insurance claim with their under writer. So they are not selling a warranty but an insurance policy with their engines.
For the same money as the base engine another company will sell you a rebuilt used engine in the form of a 383: