The aftermarket engine performance community has a long and rich history of delivering thrills and chills — back to the days of flathead Ford V8s. What became politically incorrect (and potentially dangerous) "speed" equipment in the aftermarket has now become highly engineered "specialty" equipment that commands buyer respect.
According to Frost & Sullivan's 2006 consumer study investigating vehicle owner attitudes and behaviors toward vehicle modification, approximately 4 percent of overall U.S. vehicle owners performed engine modifications. Those who did engine modifications were distributed equally across vehicle segments. Modifiers were concentrated in the income bracket above $145,000 annual income and were male but young.
Of the enthusiasts who perform vehicle modifications, 12 percent complete it as their first modification. Engine modifications are typically done in conjunction with air intakes, tires and wheels. About 39 percent of U.S. vehicle owners who modify have performance or "go" features as a priority for their modification plan.
There are many ways performance can be enhanced for gasoline engines in the aftermarket, often via bolt-on equipment and sometimes with extensive rebuilds. The industry could face accelerated demand for performance equipment to retrofit to new downsized, down-powered, lower-performance and higher-mpg light vehicles coming on the U.S. market beyond 2010.
Strategies to physically enable more air to enter for combustion with minimal pumping losses and to more freely expel combustion gases are quite effective in boosting power and torque.
The aftermarket community offers a variety of solutions. There are high-flow intake systems, cool air and low-restriction air filters and air ducts, boosting kits (preferably with air-to-air intercoolers/turbochargers) and Roots-type blowers or screw-type blowers.
Also available are low-restriction exhaust systems such as cat-backs and smooth-bore stainless steel exhaust manifolds, and valvetrain cams that provide more lift for longer duration to ensure better airflow at higher rpms.
The gasoline engine also can be rendered more thermally efficient and capable of higher power and torque via raised compression ratios, which raise cylinder pressures. So the aftermarket offers milled stock heads and/or domed pistons.
Aftermarket invited to work on electronically controlled engines
The old saying in the industry was "there is no replacement for displacement" to gain engine power/torque. Such thinking (big is beautiful) is changing to getting more out of smaller displacements. The new philosophy will diffuse into the aftermarket.
All modern street engines now are electronically controlled, which can invite aftermarket modification. The aftermarket performance community does offer drop-in engine Electronic Control Unit (ECU) chips or modules to allow more peak horsepower (through richer air/fuel ratio or more aggressive spark advance), but other attributes inevitably suffer (such as emissions, mpg, or smoothness).
It is becoming increasingly important for the aftermarket industry (including factory/OE service parts) to offer regulatory-compliant solutions, in regard to both emissions and acoustic drive-by noise (for example, from exhaust systems). In some states, such as California, with mandatory periodic chassis-dyno smog checks in many urban counties, noncompliant vehicles will be spotted. N
Larry Rinek is a senior consultant with Frost & Sullivan's North American Automotive & Transportation practice. He focuses on custom consulting engagements, frequently involving automotive powertains. For more information about Frost & Sullivan, visit www.frost.com.
