Aftermarket exhaust parts and the engine. However, the pipes do "ring" with the exhaust pulses and increase underhood noise. Headers can be ceramic coated to reduce the heat radiated in the engine compartment, and to increase the temperature of the pipes which increases the velocity of the exhaust gases. Terminology: Catalytic converters are necessary to reduce emissions but create back pressure due to the exhaust gases being forced through a catalyst, and therefore decrease high-end engine power. Many modern catalytic converters only produce 1-3 psi of back pressure, though this restriction worsens further with use. Hi-flow catalytic converters can replace the standard units
What Car? displayed alongside the dealer price so users can check whether a deal represents good value. What Car? What Car? is a long running United Kingdom monthly automobile magazine and website, currently edited by Steve Huntingford and published by Haymarket Consumer Media. First published in 1973, "What Car?" is intended primarily as a magazine for car buyers rather than dedicated enthusiasts. In addition to first drives and group tests of the latest models, it contains an extensive buyer's guide section to help consumers choose the right car for their needs and provides tips on how to get discounts on cars. In