What Are The Best Performance Upgrades For A Mopar?
Thank you if you are part of Dodge muscle car’s legacy. As a card-carrying member of the Dodge power brokers union, we love seeing the creative ways Mopar owners are fixing up their cars. If you have a 2006 or newer, then Direct Connection (Mopar Performance Parts) is an excellent place to start your upgrade project. (They’ve been supplying factory-backed performance parts for years). However, if you own an older classic Mopar, many other companies make suitable aftermarket components. What are the best performance parts that can be added to your vehicle? Read on to find out.
Most stock carburetors were built to balance fuel and air and performed well in their day, but that doesn’t mean they are best for top performance. Replacing a 2-bbl or 4-bbl carburetor with an electronic fuel injection system can offer instant power, acceleration, and fuel economy rewards. While some EFI systems can seem intimidating (we prefer more straightforward), this conversion seems popular for many classic car restorers.
The advantage of EFI systems is that they use precise sensors and solenoid valves to regulate the fuel delivery that your car needs. The injectors get pressurized fuel from a pump and fuel lines, so the exact moment your car needs an extra squirt of gas, it gets it. EFI systems can adjust to different temperature conditions instantly, making cold starts or flooding a thing of the past. Modern EFI systems have improved so much that a sound EFI system is better than any carburetor.
Now, we realize that there is much debate about adding EFI to an old classic. We understand if you are a purist who feels the best problems are still fixed with a screwdriver and a good ear. The truth about installing EFI is that it will cost you both time and money. EFI systems, like the popular Holley Sniper EFI, are expensive and require you to know what you are doing. (The installation is much more complicated than slapping a new carb onto the top of your engine).
But this conversion is a great place to start if you want to increase your beast's performance. (No one has to know that the EFI is there but you). You will be pleasantly surprised at how much better your old beast performs, and how burning precise, cleaner fuel is better for everyone (environment, wallet, marriage, etc).
Replace Headers/Exhaust Manifold
Anyone with experience with Mopars knows that replacing the headers on some classic models can be a pain in the you-know-what. But that being said, as a general rule, installing new aftermarket headers with free-flowing exhaust can help your V8 breathe better and boost performance.
There are many different headers, from long tube, short tube, and Tri-Y-type, and each has its advantages. If you are interested in a hassle-free install, consider using a short tube or Tri Y-style because long tube headers often require the most modifications (and will likely have you muttering under your breath). Tri-Y provides the best boost in horsepower if that is what you are looking for.
Most Mopar forums will tell you that replacing the headers was worth the increased performance but that doing so involved a long and detailed install. Many classic Mopar engines have very tight spaces to work in, so be sure that this is something you want to tackle before attempting the job.
Many Mopar owners have installed superchargers onto their engines to gain increased horsepower and torque. (Anytime you jam more air and fuel into your engine, you will likely increase its performance numbers). A supercharger is a forced air pump sending increased pressurized air into the chambers, which means a bigger bang and more power.
While superchargers tend to have a high-pitched whine (think of the sound of a Formula 1 racing engine), the point is that they do help achieve performance boosts. Most owners see a 30 - 40% uptick in horsepower, which can be significant. In addition, the supercharger provides better acceleration due to the increase in torque it provides, so if you are looking to race your street-legal car on weekends, this is an excellent upgrade to consider.
Many companies now have bolt-on supercharger kits that are relatively easy to install and require few modifications to the engine. (We prefer not to have to replace the hood on our classic if we don’t have to). And because superchargers tend to have less heat flowing through them, they last longer than other forced air induction systems like the turbocharger. (Turbochargers are also harder to install on Mopar engines).
The only drawback to installing a supercharger onto your classic Mopar is its cost. For example, a 440 RB supercharger kit like the Paxton NOVI 1200 is almost $5k, but for muscle heads who crave power and speed, installing a forced induction system is worth the expense, (We realize that there are some of you out there who are riding around with more recent Hemi’s, so we priced one for a 5.7L V8 (Edelbrock E-force), and it was close to $9k
Some of you are considering adding a turbo to your engine, which is another way to boost power. A turbo will usually have some lag (where superchargers don’t) and may require more engine modifications. Exhaust gases power turbos, and while effective, don’t produce the kinds of hp increases on a Mopar big block that a supercharger does. But then, it is up to the Mopar owner as to which direction they want to go. (Turbos are less expensive). It might make more sense to go with another way to boost performance.
The Heads Win
One way of improving performance is to replace stock cylinder heads with a performance aftermarket unit. A performance head will pump more air into the system, boosting horsepower. Choosing an aluminum head can decrease the engine weight by 50 lbs, making the engine more efficient by not having to work so hard.
One of our favorites is the Edelbrock #61805 Performer, a perfect fit for an RB like the 440 V8. While the increase in horsepower varies depending on the engine, driving habit, and other factors, most Mopar engines will see a 25-hp boost.
Today, there are so many performance aftermarket heads in aluminum (and cast iron) that choosing one can be a dizzying affair. Choosing the right head will depend on what you are planning to do with your rebuild and the type of engine you are working on. Remember that when you refreshen the head, it is also an excellent time to install new valve springs.
Add A Tank . . .
Let’s clear up some misinformation that seems to scare people away from nitrous oxide. The fact that it is dangerous to use, will cause damage to engines, and create a fiery crash is simply not true. The reality is that a correctly designed, nos system operated within normal parameters and not abused will have little to no effect on damaging an engine. (As for the crash part, that’s up to the driver, we think).
If you remember your high-school chemistry class, nitrous oxide is two parts nitrogen to one part oxygen. When exposed to heat (like in a combustion chamber), nitrogen breaks down and releases oxygen. When the spark plug fires, the extra molecules of O2 ignite, creating a higher fuel burn, which means more horsepower. Nitrogen also acts as a cooling agent by reducing the intake temperatures by 15 - 25 degrees, so when the Big Bang happens, and the extra O2 is ignited, the excess power doesn’t overload the system.
While there will always be horror stories about the dangers of explosion from nitrous, installing and using a nox system can reap benefits when short bursts of power and speed are needed. Nitrous kits are less than $500 and can be installed with minimal fuss. While we don’t recommend nitrous for a daily driver, we understand their use on the track where every second counts.
Convert Those Brakes
When most people think of performance, they often think of ways to increase the engine's power, but isn’t stopping your car just as important as speeding it down the track? Most classic muscle cars didn’t have disc brakes as standard equipment (although it might have been an option). If you are one of those lucky folks with drum brakes, you should consider slapping some rotors and calipers onto the front wheels at the very minimum.
The problem with drum brakes is that they are inefficient for slowing your car. (I know some old-timers are rising out of the rocking chairs, but it’s true). Drum brakes might still be used in some applications, but the only reason is that they are cheap to make. If drums were the way to go, automakers would never have converted to discs in the first place.
Any Mopar build is worth spending a bit to protect (think of disc brakes as a cheap form of insurance). Considering the amount of work that has gone into your build, the last thing you want is to plow it into some stupid idiot who slams on his brakes unexpectedly. Disc brake kits are easy to install and don’t require the attention that drums do. Many companies make brake kits (our favorites are Dr. Diff, Baer, and Wildwood). You will spend about a grand to upgrade your front brakes, and if you decide to do the rears (we highly recommend this), plan on spending more.
Improve The Suspension
Since suspension systems are often overlooked, we want to mention it here. If you plan on upgrading your motor's performance, make sure that your car’s suspension can handle the new torque. Upgraded front and rear sway bars can keep your car from getting squirrely in a curve, improve its braking capability, and give your Mopar balance.
The critical thing to remember is that suspension is an area where “bigger is not always better.” While a massive sway bar might give the car a ‘beast-mode” look, if it is too large for your car’s other components, it will affect its performance. Use a sway bar that works with what you are trying to accomplish with the car. If it's a daily driver, think smaller, and if you are headed track with larger tires that you want to stick on the pavement, think bigger.
Our favorite purveyor of suspension components for Mopar muscle is Performance Suspension Technology (they offer free shipping to the lower 48). Still, there are several other retailers who are good, as well.