The desire to improve engine performance is as old as the car itself. We can go back in time to the earliest days of the automobile and find people who wanted to go faster than the other guy. That meant they’d have to modify the vehicle, particularly the engine. Times haven’t changed. In 2016, we can still find people who want to go faster than the other guy. But, in order to do this, the first place to start is under the hood.
Modifying a late model engine is not as easy a task as it was back in the muscle car, pre-emission era. Back then, your typical motorhead would install high-compression pistons, a street cam, larger valves and a bigger carburetor and it was off to the drag strip. Today, the performance of a vehicle is tied to computer control modules, making vehicle modifications more difficult. Though changes can still be made, they’re a bit more subtle.
ENGINE PERFORMANCE REVIEW
Mechanically, the modern automotive engine is pretty much the same as it always has been — pistons, valves, camshaft, crankshaft, spark plug. It all works the same way. The Otto cycle has not changed. The major differences are found in the fuel and ignition systems.
Fuel injectors have replaced the carburetor. And with one fuel injector per cylinder, you can’t swap out the stock 2-barrel carb for a 650 Holley® double pumper. And, thankfully, an advanced electronic system has done away with the coil, condenser, ignition points and distributor ignition system. Ignition and fuel injection timing are computer-controlled to maximize performance and minimize exhaust emissions, while the exhaust stream is continually monitored for oxygen content to measure efficiency.
Sure, you can go into the aftermarket and buy a performance chip to replace the standard one found in the powertrain control module (PCM). This chip will increase horsepower by changing the ignition timing events and pulse width of the fuel injectors (the length of time the injector is open). But, be forewarned, this is not recommended by FCA US LLC, and the installation of this chip voids your customer’s warranty
MORE AIR FOR MORE POWER
So, what can you do to increase performance? If we go back and review the basics of engine combustion, we’ll see that the amount of power produced is directly proportional to the amount of air you can put into it. That’s the role of a supercharger (driven directly by the engine) and turbochargers (driven by exhaust gas). The aftermarket provides both components, but with a high price tag.
FCA US offers a complete line of cold air intake replacement filters. These air filter elements allow an increased amount of air into the intake system, and more air means more power. The cost and time to do this modification is very affordable.
In the Body Repair article in this issue of Mopar® Magazine, we discussed hood scoops. The premium system includes a cold air induction system which also allows an increased amount of airflow into the engine. Cold air is denser than warm air, so if the air can be cooled before it enters the engine, more air can be used, increasing power.
GOING WITH THE FLOW
Increasing the amount of air in the engine also depends on the efficiency of the exhaust system. Combustion in the engine cylinder is not complete, and all of the byproducts of combustion are not completely removed from the cylinder. Exhaust systems are designed to maximize the flow of exhaust gas from the cylinder. Mopar offers a line of cat-back (from the catalytic converter and back) exhaust systems to improve exhaust flow.
These stainless steel exhaust systems are free-flow designs available for the Charger, Challenger and Dart. Built using T304 stainless steel with mandrel bent tubing, these systems are complete with bands, mufflers and polished tips. A cat-back exhaust system will add personality to your car with a deeper tone that’s overall louder and more aggressive while adding horsepower and torque. And, it meets all FCA US standards for corrosion.
MORE VENOM FOR YOUR VIPER
Race headers and performance exhaust systems are also available for the Dodge Viper (2003-2010).
The race headers (P5155828) are constructed of heavy-duty stainless steel. They are equipped with a 5-tube flange that allows easy installation without removal of the engine. A 5-into-1 collector allows for maximum torque and horsepower gain. The primary tube diameter is 1-3/4″. Expect up to a 40 horsepower gain when equipped with the race exhaust system and performance engine controller. Additional installation recommendations include forged pistons and spark plug wire heat socks. Plus, the header gasket and J-pipe are not included.
The performance cat-back exhaust system (P4510608) was developed for use with the above Dodge Viper headers. These 2.50″ pipes with single angle-cut tips, exit on each side of the vehicle and contain all the necessary hardware and mounting brackets.
Note: The Dodge Viper headers and exhaust system are not legal on pollution-controlled vehicles or vehicles registered for highway use.