Inputs on a home built 318 for red light to red light fun
This is what I would do. It maybe a slight overkill, but, I will call that an error on caution as 12’s in the street IMO is not what I’d call fast anymore.
Based on your listed parts in your first post & with a minimal change in parts, I would;
Shot for a compression of no higher than 10.5-1 with the iron heads. You’ll probably require 93 octane to run this. A 1/2 point in compression down @ 10-1 is safer and not a huge issue.
Select a piston for this job.
Going from top to bottom of the engine;
K&N filter lid on a K&N filter with as much height as the hood allows & to be honest, going through the hood for air filter clearance should be done. Use a hood scoop to help feed the carb and seal the carb to the hood.
Carb - A 750 Holley. A capable and inexpensive model like a Brawler can be used effectively.
Intake - RPM-AG deep port matched.
Cylinder head - 1.88-1.60 valves race prepped in a race ported 318 head. Equip the head with the valve springs for the cam suggestion below with the matching valve springs of the cam along with race styles 7* retainers and locks.
Your rocker arms are OK. I’d rather move to aluminum roller rockers. But using what you have, you can help out the package by having the rockers worked on and set up for a true dead on 1.5 ratio.
I normally do not give cam advice anymore since that’s a big can of worms. But I will say that the old MP books suggest there cam. There very expensive and the one below is maybe available today though another maybe substituted. It’s the MP mechanical cam, 296-.557-110, part number 4120655. I’d search for a similar cam.
Headers - I may catch flak for the suggestion of a 1-3/4 header, but that what I would do myself. Into a 2-1/2 exhaust. If you dyno this engine, find out the length of pipe past the header collector that makes the most torque and cut it there and add a pressure wave cancellation box. The pipe should be the same size as the collector and only reduced in size after the cancellation box in a smooth manor. The cancellation box should be the same cubic inches as the engine at a minimum.
The rest of the car…. Scatters shield for the clutch, driveshaft safety loop, 4.88 gears (since you have them?) Super stock springs though I like the Caltrac or Assassin leaf spring set up better. 9X28 tires. Street slicks. (Slicks with tread) Move your battery to the trunk. Install and electric fuel pump and regulator, light weight wheels, frame connectors & torque boxes, up the ignition abilities. Lighten the car up as much as possible
I myself would rather use ported Edelbrock heads. As the iron is expensive to get worked on. I’m not experienced on porting and if I tried, my hands are not vibrant enough anymore to hold the die grinder long enough to get a port done in a week much less the other 15 ports.