Though somewhat overshadowed by Chrysler's Hemi and big-block powerplants, the small-block Mopar engine has always been an economical way to go fast, especially if installed in a lightweight A-Body. In stock form, these engines make respectable power and also respond well to modifications, making the small-block Mopar a great choice for street, strip, or dual-purpose vehicles. Lately, the small-block Chrysler engine has gotten a little bigger, with stroker kits available that can increase displacement to 440 ci or more! So if your ride has a small-block, don't feel self-conscious, there are plenty of ways to make your small-block perform as well as your buddy's big-block. Just follow along as we detail both bolt-on and in-depth performance upgrades for the small-block Mopar.
Bolt It OnThe easiest way to improve your small-block's performance is by simply bolting on some performance goodies. There are literally hundreds of aftermarket companies supplying thousands of performance parts for the small-block Chrysler, so finding what you need is usually as simple as surfing the internet for your favorite performance company's web site. Since an engine needs to flow a high volume of air and fuel to make power, performance intakes, carburetors, and headers are logical bolt-on components that can make a big difference in the performance of your small-block. Even having a solid electronic ignition is crucial in making power.
Exhaust
Increasing the air flow into any engine will only help build power if the spent gasses are given an easy way out of the engine. Factory cast-iron exhaust manifolds are heavy and don't have the flow potential for real performance, so we recommend replacing them with a good set of headers. For the cost, you'll probably notice a bigger difference in your car's performance by adding headers than you will by doing any other bolt-on upgrade. A low-restriction exhaust system should always back up the headers as well. We prefer to use no less than a dual 2 1/2-inch exhaust diameter with a crossover tube in ours. X-crossover systems have also been shown to dramatically improve performance. Several aftermarket companies build exhaust systems for popular Mopar applications, but be sure the tubes are mandrel bent for the best flow. Remember, an exhaust system doesn't have to be obnoxiously loud to flow well. Companies such as Flowmaster and Dynomax are manufacturing great, high-flow mufflers that won't give you permanent hearing damage during normal driving.
Induction
If you are fortunate enough to have factory four-barrel induction on your small-block, you are already ahead of the game, but improvements can still be had by bolting on an aftermarket induction system. Factory intake manifolds were designed to be easy to manufacture, so performance was sacrificed. Modern aluminum intake manifolds not only flow better than the factory units, they are significantly lighter. Also, by matching the intake manifold to other engine components, the efficiency of the entire combination can be improved. For a mild application, dual-plane intakes will greatly improve torque and offer slightly better top-end power. For more aggressive applications and higher-rpm usage, single-plane intake manifolds are a better choice.
Even if you're LA engine was originally equipped with a four-barrel carburetor, there is likely power to be had by installing a newer, more efficient unit. If you're looking for an economical replacement for your Thermoquad, check out Edelbrock's Thunder series-it's a direct replacement. As carburetors age, they wear out just like other components. While rebuilding can recapture some of the carburetor's original performance, throttle-shaft wear, warpage, and broken ears are all good reasons to replace that thirty-something-year-old carburetor. Modern carburetors from manufacturers such as Edelbrock, Holley, and Barry Grant have more efficient venturi designs, which can mean more power from your small-block. For mild applications, vacuum secondary carburetors in the 500- to 650-cfm range work best. If you're combination is more exotic, you'll need 750 or more cfm of flow to accomplish your goal. In any case, a new carburetor is a great way to improve the power, economy, and reliability of your small-block Mopar.
Wanna Swap?
If wrenching on your own engine isn't your idea of fun, how about a crate engine? Mopar Performance has small-blocks of various displacement and power ratings that are ready to install, making it easy to get the power you desire.
Get Into It
There is a limit to how much performance can be added by simply bolting some aftermarket goodies onto your small-block. To see dramatic improvements in power, improvements must be made internally. The Chrysler small-block has always responded well to cam and cylinder-head swaps, and now there are several companies manufacturing stroker kits to increase displacement up to 440 ci! While this may be a little much for your application, chances are you can find more power simply be swapping the camshaft or cylinder heads. Several companies provide kits that include the cam, intake, and heads in a matched set. While adding a stroker kit may be a little much for the weekend wrencher, cam and head swaps are easier than you think, and the results can be impressive.
Need to Bolt-on More Power?
If you just can't get the power you want by bolting aftermarket components to your engine, there is the option of a power adder. Nitrous oxide injection kits are easy to install and can improve power dramatically. Be careful though, power adders such as nitrous oxide, a supercharger, or a turbo will quickly find the weakest link in your engine! Parts like forged pistons are usually a good idea if you plan to run nitrous.
Additional fuel and air will do you no good unless you can light the mixture efficiently. A good ignition system will not only provide more power, but will improve economy and reliability. Units such as this Pertronix billet distributor come ready to run and are an excellent upgrade.
Even if your car is already equipped with electronic ignition, higher-rpm efficiency can be improved simply by adding a performance ECU from Mopar Performance.
Ignition
If your Mopar was built after 1971, then you're lucky enough to have one of the best factory electronic-ignition systems ever built. Even so, increases in performance can be had by simply adding a more powerful coil or a more aggressive ECU to your existing ignition system. Older Mopars equipped with antiquated points-style ignition will always benefit from the installation of electronic ignition. For applications with increased cylinder pressure, or if a power adder is used, a high-energy coil and good electronic ignition is mandatory. Several companies manufacture ignition systems from individual components to complete kits. Along with improved performance, upgrading the ignition system nearly always nets better economy and enhanced reliability.
To really multiply your newfound torque, try a set of steep rear gears.
Don't Forget the Rest
Remember, making more power means the rest of your car will need to be upgraded as well. Your fuel system will need to deliver more fuel; your cooling system may be taxed and need to be upgraded; and to take advantage of that bigger cam, you'll need a looser converter and, quite likely, steeper rearend gears. Since a more powerful engine accelerates quicker, you'll probably need to upgrade the oil system as well. It's not the individual components but the complete package that makes a true performance car. If you're unsure about what parts will work for your application, we encourage you to call one of the many manufacturers' tech lines for assistance. By paying attention to details and using an effective combination of parts, you can have your small-block-equipped Mopar running with the big-blocks in short order.
