I guessing you have a 318? With a wary eye on the smog commies, select components to build torque [port velocity and cyl pressure]below 4500 rpm. The ports in the heads/valve sizes are too small to make any appreciable torque above that anyhow. I like the Hughes HEH1019. 210/219 dur @ .050 .461/.489 lift, with a 112 deg lobe separation. Idles like a stocker. Get the matching valve springs.

An Elelbrock Performer intake,[or any small port dual plane] and a 600 cfm Holley vacuum secondary set to open @ 25-2800 rpm, and a set of 1 5/8" headers with the longest tubes you can find. [No shorties] Rework the dist. so the advance comes in quicker, or get a Mopar performance replacement. More compression helps torque, but it's not easy to accomplish,and super no lead gets expensive on a daily basis.

If you have 3.21 gears,consider a set of 3.55s for a daily driver, 3.91s and lower if you don't do much highway driving. That will help seat of the pants feel quite a bit.

Most everything but the cam package and gears can be bought used to save some bucks.

 

To add to you making your choice on carburetor cfm, here is a equation. Too big is not good
Street carb Cfm
Cfm = max RPM x CID Divided by 3456 x .85

lets say 5500 rpms x 318 / 3456 x .85 = 430 cfm minimum needed to achieve your 5500 rpm plateau. Flat tappet hyrdraulic engine do not go much higher than 5500. If you have the 360 ..... 5500rpms x 360 / 3456 x .85 = 486 round it up to 500cfm

Theoretically your max is between 6000rpms & 5500 (to me at least). I have not seen a stock hydraulic flat-tappet go above 6000rpms. Maybe if the engine was built like a racing mill it could possibly go to 6000 and little above but that depends on your valve train.

 

It has stock manifolds, no cat. and a 40 series Flow

 

Yes I have a 318 the same and only motor that has ever been in that truck sence it was built in 85

 

Yeah Hemi's 100% right, too big and you'll have hell with low RPM fuel delivery. Not enough velocity through the carb,and it won't pull fuel from the boosters. Seems bass-ackwards, but a carb that's too big actually makes one run lean. A 600 is too big for a bone stock 318.

And 83's right too. Unless you do some mods to the 318, you'd just as well leave the stock 2bbl on it. Some 318s came from the factory with a 650 cfm Quadrajet, but what the hell for? The stock cam's only .374 lift with a duration measured in milliseconds. Seems major overkill to me.

 

at the very least to run a four barrel, I personly would have the valves reground, having a good three angle grind put on them, if you have a few extra bucks it wouldn't be a bad idea to have a very mild porting job done, but keep it very mild, I have known guys to get wild on porting and they created turbulence in the runners and... well a two year old on a triycle had a better holeshot from a light. If I recall correctly I believe it is blackjack that makes a big bore self scavenging header that is good for low end. Again, personnely I'd run no less then a 2.25 dual set up with an h pipe. Indeed that is the same set up I am working on for my truck.

 

Leave your 2v on the engine, Buy headers -> 1 5/8" long tubes like Lugnuts mentioned and piece the rest of the exhaust together. DO not go to huge 3" pipes, stay between 2 & 2.5" pipes, maybe 2 to 2.25". The reason behind that is because if you have TOO MUCH room in your exhaust system, the exhaust will flow less efficient. I will end that with Exhaust is very complex, very complex! Plus playing around with header wraps too might help your power go up or stay the same. TRIAL & ERROR TESTING BOSS!!!

Take the intake manifold and carburetor bolts out and replace them with stainless steel bolts. The stainless steel material transfers heat at a slower rate that of mild steel, keeping your air charge a tiny bit cooler. Cooler charge = more dense air charge = more power output potential.

What carburetor is on your truck engine right now, Rochester, Carter?

If you want to go into more detail into a system, just ask us.

 

It has a

 

Holley huh, never knew/heard before about the old mopars using those. Does it have any electronic emissions junk on it?

 

Also, find the carb number (I dont know how many digits a Mopar holley would be), search that number online, and/or, call Dodge to see if they have a cfm rating in the archives. That is if they have some literature that old. Other than that, do a thorough rebuild/cleaning if you have not already. Doing that will make it easier to tune after your exhaust is installed.