I'd go with a 4 barrel intake, HEI vacuum GM dist, Holley (600) or Q'jet (650) 4 barrel set for about 300 HP, and any short headers with 1 5/8" tubes. If manual, be careful with clutch linkage. Hydraulic clutch isn't an issue. The dist timing could start at 10-12*. Then run the engine and ramp it up gradually under a load until you hear detonation, then back off a couple degrees...for sure until detonation is gone. Keep in mind that an engine set up as I describe does not require an ECM. You can keep it in the system to short cycle the fuel pump. The carb only requires about 4 lbs of fuel pressure to function well. So the fuel pressure will require regulator or a different fuel pump in order to deliver 3-5 lbs of fuel pressure. The engine would be similar to late '60s in function. Good overall performance and easily modified without major additional carb, exhaust, intake changes. You can run regular or premium fuel, depending on the advance settings. All guages will function normally, but the AC will require circuit changes in order to function without a signal from the ECM. You will not need O2 sensors. A street cam such as a GM "Hot Cam" will add considerably to the overall feel. And still allow for reasonable towing. The 1 5/8 headers are high torque items, so if not towing, 1 3/4 could be used.
The big issue is your transmission if 4L60e. You'll either have to swap to a 700R4, or stand alone trans controller.
If manual, no problems with any engine mods. Your VSS feeds the dash so while the ECM copies the VSS signal, but the speedo and cruise work without an ECM. These changes are not cheap, but they are one time expenses that allow continued engine performance upgrades without remapping, additional tbi mods, fuel ratio issues, and maps that just ain't quite right. Both Holley and Q'jet can be easily jetted for whatever. The Q'jet is easier (IMHO) and cheaper to adjust calibration. Use popular dual plane intake, such as Holley Warrior or similar. The only downsides to this setup is it isn't emission legal, and carbs are cold natured until engine reaches operating temps in cold weather. Other than that, a good carb is far more dependable than GM tbi or fi. And this setup can be diagnosed and repaired without major expense, even in the back country. I ran that (30 year old) Q'jet in the above picture for 5 years without a sneeze. People forget how dependable those things are. A good addition to the above is installing an air/fuel ratio and electric fuel pressure meters for monitoring the jetting while setting up. Once done, its nice to watch your work.
The key is dont fall for "bigger is better". Stay with reasonable sized cam, carbs, intake, exhaust. A small block is a great street engine if done up right.
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