#torque PHOENIX, AZ

Engine Performance Q&A


Can a cold air intake give my engine too much air flow?

No, a motor can only draw in the volume of air that is allowed by the motors stroke, bore, and number of cylinders. A performance intake system and air filter is not capable of increasing the volume of air the engine takes in, it can only change the density and velocity of the air flowing into the engine.

Does higher filtration mean a better performing intake system?

While 99% filtration efficiency is a very good achievement, air filter efficiency is just one measure of filter performance. There are several measures that you need to consider when evaluating a performance intake system including restriction, service life, and capacity. These addition measure factor in the velocity capacity of air flow, how much dirt an air filter can hold, and the life of an air filtration system. When a performance air filtration manufacturer claims their filters consistently achieve 99% filtration efficiency, it typically means they are sacrificing other performance characteristics to achieve that filtration rating. Generally a filter which achieves 99% filtration is sacrificing air flow capacity and velocity resulting in restrictive properties that limit your engine’s performance capabilities.

How will a cold air intake system impact my vehicle’s fuel economy?

Because performance cold air intake systems allow the engine to breathe better and reduce the heat in the air flowing into the motor resulting in more oxygen density, cold air intake systems generally improve gas mileage. Keep in mind that there are several other factors to consider including other performance parts such as a supercharger that you have installed on your vehicle. If you’re aim is to boost engine power, you’re typically looking to burn more fuel in exchange for more horsepower and torque. As a result, your gas mileage will go down. However, if you only install a cold air intake system on a stock car, truck, or SUV, you can generally expect to get more miles out of every gallon of gas.

How often will I need to clean and re-oil my performance air filter?

Maintaining your performance air filter is one of the most important tasks required for not only extending the life of your performance intake investment, a dirty filter will impact engine power and fuel mileage. When your air filter is dirty, it will restrict the airflow into your motor and degrade the life of the air filter. Driving conditions play a key factor in how often you will need to maintain your filter. Most manufacturers recommend you clean and inspect your air filter at least every 25,000 miles, however, if you’re driving in terrain that has a lot of dust and dirt contaminants, you should inspect your filter more frequently.

Remember to use manufacturer approved air filter cleaning kits. Most aftermarket performance air filter manufacturers sell a cleaning kit that will include the oil which is specifically designed to match the materials used in the air filter. K&N provides a good step by step guide on air filter cleaning steps here: How to Clean K&N Air Filter Products

If you are in the Phoenix, Tempe, Scottsdale, Mesa, Glendale or surrounding area, you can purchase an air filter cleaning kit at our shop.

Will a performance exhaust system give me better gas mileage?

Yes, a more efficient motor uses less fuel which in turn will improve your miles per gallon under normal cruising conditions. When an exhaust system incorporates proper diameter, mandrel bent exhaust tubing with a flow through design, the exhaust gases from the combustion process will exit faster with a higher temperature than factory exhaust systems. As a result, you will enjoy a boost in horsepower when you plant your foot and better gas mileage when you’re cruising on a road trip. The larger the vehicle, the bigger the engine, the higher the load, which results in greater savings in fuel consumption.​

Why do some performance exhaust systems cost more than others?

The cost of a performance exhaust system is highly dependent on the metals used in the exhaust manufacturing process. The most commonly used metals in cheaper exhaust systems are rust prone mild steel, aluminized steel, or inferior 400-series stainless steel. While this results in cost savings up front, these metals result in a low-quality product that will rust away or fall apart when exposed to the harsh elements of the road.

High quality performance exhaust manufacturers, like BORLA, only use authentic stainless steel which not only costs more foot, but also require higher manufacturing costs. The process of cutting, bending, and hand welding genuine stainless steel requires expensive special equipment. In addition, the highest performing exhaust systems require substantial investments in research and development to engineer products that will consistently perform better and last longer.

How does a performance exhaust system impact sound and performance?

Aftermarket performance exhaust systems incorporate a straight-through design which increases exhaust gas velocity and allows air to run through the engine uninterrupted. The process removes exhaust flow restrictions so the cylinders can evacuate faster which allows incoming oxygen flow to enter the cylinder faster thereby producing more power. The result of this entire process, paired with modifications to the design and sound dampening materials used in the muffler, products an enhanced exhaust tone which gives you the performance automotive sounds car enthusiasts love.

How much horsepower can I expect to gain with a performance exhaust system?

A motor is an air pump, performance exhaust systems allow an engine to pump and flow more uninterrupted air through the system. The result of more free flowing air is the potential for more horsepower and torque. The actual horsepower gains will depend on your fuel system’s ability to provide enough fuel to match the additional air flowing through your engine. Typically, you can expect 5 to 15% more horsepower out of a performance exhaust system. To get the most out of your aftermarket exhaust system, you should match your performance exhaust system with a cold air intake and engine tune.

Will an aftermarket exhaust or cold air intake void my factory warranty?

No. If you install an aftermarket exhaust or cold air intake from a reputable manufacturer, the parts will be 50-state emissions legal. It is illegal for a car dealer to deny the original equipment warranty because of an aftermarket parts installation.

If your vehicle dealer or manufacturer fails to honor emissions or warranty claims, you can contact the EPA at (202) 260-2080 or www.epa.gov. If a federal warranty protection is denied, you can contact the FTC at (202) 326-3128 or www.ftc.gov.

If you would like to view the Magnuson-Moss Warranty Act of 1975 you can click here: Magnuson-Moss Act

Is a bigger pipe and muffler better for performance?

No. Just throwing a larger exhaust pipe and muffler on your vehicle will not result in horsepower gains. In order for a performance exhaust system to boost car, truck, or SUV performance, there has to be a balance to the design. If the exhaust pipe is too large, the velocity of the exhaust gas exiting the motor will be reduced which will rob the exhaust system of its thermal efficiency. Exhaust manufacturers often disprove the racer mentality that larger is better during the research and development. Issues like volume versus velocity have a significant impact on exhaust performance.

What’s the difference between a factory Stainless Steel exhaust and a performance aftermarket exhaust?

The biggest difference between a factory Stainless Steel exhaust and an aftermarket exhaust system is the materials used. Most car manufacturers us a low grade, 400 series Stainless Steel in their factory exhaust system. While 400 series Stainless is a big improvement over the rust prone steel systems, however ferritic Stainless Steel is magnetic and still prone to degradation in the road elements. The Austenitic stainless steel used in higher grade performance exhaust systems exhibits a higher hardness, yield strength and ductility which makes it much more resistant to corrosion.

Is an “X” pipe design better than an “H” pipe?

Aftermarket exhaust manufactures have conducted extensive testing on various exhaust system designs and they have determined there are no significant performance difference between an X vs an H pipe design. There is however a noticeable difference in exhaust tones between the two designs. An X pip will change the exhaust sound to a higher pitched exhaust tone.

If I install an aftermarket engine tune with a handheld tuner, will my vehicle dealer know the vehicle has been tuned?

​All handheld engine tuning manufacturers recommend returning your engine programming back to stock tune before taking your car, truck, or SUV into a factory dealership for service. One of the benefits of a handheld tuner is it’s easy to save several different tunes to the programmer so it’s easy to change your tune with a few clicks of a button. Also, most handheld tuners will not leave ghost data or a data footprint on the vehicle, so once the vehicles ECU is changed back to the factory the dealership will have no way to determine changes were ever applied to the ECM.

When considering a supercharger, what is the benefit of a centrifugal vs roots or screw-type supercharger?

There are many technical differences between a centrifugal and roots supercharger such as reversion and thermodynamics that could take a long time to explain. With that said, a simple comparison of the two supercharger styles is the difference between low-end power which drops off on positive displacement superchargers and the linear power provided by centrifugal style superchargers which increase engine rpm. Rather than working against the against the existing power band, the linear curve from a centrifugal supercharger compliments a motors existing power band. Another significant benefit of centrifugal superchargers is they have higher efficiency requiring a smaller amount of work to compress air than a roots supercharger. Centrifugal superchargers require less energy to make power and the power created by the supercharger is more usable power.

Why should I choose a supercharger over a turbocharger?

The biggest difference between a turbocharger and a supercharger is heat. The biggest enemy of the internal combustion engine is excessive heat. Too much heat can cause everything from engine detonation which occurs when a piston reaches top dead center and causes catastrophic engine failure, and premature wear on engine parts. A turbocharger uses extremely hot exhausts gases to spin the turbines used for air compression, when you route those hot gases around your motor, it will significantly raise the temperature under the hood. Another turbocharging byproduct is the significant increase in exhaust backpressure that is caused by a turbocharger. This makes it more difficult for exhaust gases to scavenge from the cylinder head of each compression cycle. It will also lower your engines overall efficiency. The combination of additional heat and backpressure forces you to either run lower boost or compensate by pulling timing in your tune which results in lower horsepower gains.

How will a supercharger impact my vehicles gas mileage?

The impact a supercharger has on your fuel economy is heavily depended on your driving habits. Many people who install a supercharger tend to develop a heavy foot due to the joy of driving a car, truck, or SUV with some serious horsepower and engine response. If you develop a lead foot, your fuel mileage is going to suffer. Heavy foot aside, under normal freeway driving when your supercharger is not under boost but is still increasing the efficiency of your motor by forcing air through normal restrictions like an air filter, you will actually enjoy a boost in fuel mileage.

How will an aftermarket supercharger impact the life of my engine?

The longevity of your motor is heavily depended on how well your vehicle is maintained as well as your personal driving habits. If you maintain your vehicle properly and not abuse the motor by jamming on the accelerator every chance you get, your engine life should remain generally unaffected. A stock vehicle will even show signs of premature aging if not properly maintained and cared for. If you are running your vehicle in racing and towing conditions on a regular basis, the motors life will suffer.

A supercharger is simply a larger air pump that will improve the air density and flow into your engine. While under boost, the additional condensed air will require additional fuel to enrich the air fuel ratio in your combustion chamber. If you are experiencing detonation which can be identified by a pinging noise coming from your motor, it is a good indication that your vehicle is not tuned properly for the supercharger. Detonation typically results from a lean fuel condition, too aggressive of a timing curve, or lower octane fuel. If you push a motor that is experiencing detonation, you risk severe damage and reduced engine life.