Hello guys, I am new to the boards and pretty new to cars, but luckily I have some friends that are relatively knowledgeable about them. With that said, I have a 1965 Dodge Dart 270 (4-Door) that I am able to toy around with and I was looking for the most effective ways to boost performance out of it without doing anything too dramatic. My engine is a 4.5L V8 LA Naturally Aspirated one. It is 273 cubic inches.
As far as I know, everything else is stock. So, the major things that I have complied together, with the help of my friends, is to do the following:

1.) Install new headers.
2.) Install a 4-barrel carburetor in place of the old 2-barrel one.
3.) Install a new true dual exhaust system.
4.) Purchase an ECU module. (This is where I am unsure about this all. I didn't know my car had one but apparently on Ebay they have 2 for sale for my car and trim.)
5.) Mill the engine to get the compression ratio up to 10.5-11.0:1
6.) And to get a more aggressive camshaft.

That is pretty much all I know what to do. I mean, if this was a more recent car, I could install a turbo and cold air intake, etc, but it isn't. Can I have some input from you more experienced car people? What else should I consider doing, in complementary terms with the other upgrades?

Before you go nuts on changing your car, I strongly advise you to get it running well in stock form and then learn about the modifications you want to make before you go buying parts and just throwing them on there. It isn't a Chevy. There is no "right recipe" to build the approved hot rod car.

If it were my car, the first things I would spend my time and money on would be rebuilding and upgrading the braking system, the suspension system, and the ignition system. Before you start even thinking about what modifications to make, you need to set a realistic set of parameters of the intended use of the car. Drag racing? Daily driver? A mix of the two? This will dictate what parts you want to buy to make your motor and transmission and rear axle combination work best for you.

Step one- buy the factory service manual to your car and read it.
Step two- read it again.
Step three- search around on this site to learn about what upgrades can be done to the basic systems on your car (suspension, brakes, etc...)
Step four- realistically plan out how you will use your car
Step five- evaluate what you already have and see what needs to be changed to meet your goals.

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Casually looking for a Clifford hyperpak intake for cheap.

Welcome aboard AlxPachinox.

Reed’s recipe is the best plan, one really should get their car handling well, and stopping better with split duel pot master cylinder feeding front disk brakes as a minimum before adding power. These cars can’t safely compete with modern iron on the road these days with nine inch drum brakes, and sloppy handling.

Brake upgrades are rather inexpensive with used parts, or more expensive using manufactured kits, suspension and steering is a bit more costly. Once the suspension, steering, and brakes are up to snuff, that old car will be a blast to drive and will be able to easily keep with the new stuff.

Reliability is another area that is important; your 50 year old electrical system will have to be addressed probably sooner than later. Depending on how handy you are, the project can be inexpensive and somewhat labor intensive repairing your own harness, or expensive purchasing a complete set of harnesses and somewhat labor intensive.

Pick one project, tool up for it, get it completed, and then move to the next one.

Engine building and drive train design have to be carefully planned out before a wrench is picked up. All the parts have to work together or one will end up with an expensive turd under the hood that sucks gas, and can’t get out of its own way. Those little 273’s can be made to go, but it won’t be as cheap and easy like a Chevy small block is with a hundred off the shelf prepackaged builds waiting to be bolted up.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

A 318 is a bolt in replacement and everything you do to the 273 can also be done to the 318 with better results. For best results treat the 318 as a 340 with smaller cylinder bores.

If this is is a '65 273, the cylinder heads have a different intake manifold bolt inclination then the '66 and later LA heads so aftermarket intakes will be hard to find. The stock exhaust manifolds are fairly restrictive and there aren't any readability available headers for this combo. When 340 manifolds were dime a dozen, they could be swapped with a little work on the drivers side to clear the steering coupler. Newer manifolds may also be made to work. For the best exhaust setup, run 2 1/4" from the manifolds to a Y pipe and the 3" out the back. Otherwise you will have a pipe that sit very low to the ground and it will hit all the speed bumps. A well built 318 is a litter to much for the chassis, you should install frame connectors. You should also update the brakes to match the power.

Good luck, you could have a very fast car with a little work. Been there, done that and updated to a '68 and later chassis, because there is more room for stuff.