Originally Posted by 02'subie_dude

A buddy of mine has an 06', slap a vf39 (sti), cobb accessport, exhaust, larger top mount and you have a mid to high 12 second car.

Originally Posted by Aussie Dave

remove seats, a/c motor, and anything else you can get rid of in the car, weight reduction will give your car more horsepower on the butt dyno!

Originally Posted by Wikipedia

Naturally-aspirated engine
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A naturally-aspirated engine or normally-aspirated engine (or "NA" - aspiration meaning breathing) refers to an internal combustion engine (normally petrol or diesel powered) that is neither turbocharged nor supercharged. Most automobile gasoline (petrol) engines are naturally-aspirated, though turbochargers and superchargers have enjoyed periods of success, particularly in the late 1980s and the current 2000s era. However, most road-going diesel-engined vehicles use turbochargers, because naturally-aspirated diesels generally cannot offer suitable power-to-weight ratios to be acceptable in the modern car market.

Air or fuel-air mixture is forced into the cylinders by natural atmospheric pressure upon opening of the inlet valve or valves. The pressure within the cylinder is lowered by the action of the piston moving away from the valves (so as to expand the volume available for incoming air). In some cases the lowering of the cylinder pressure is enhanced by a combination of the speed of the exhaust gases leaving the cylinder and the closing of the exhaust valve at the appropriate time. A tuned exhaust can help with this but generally only works at a narrow range of engine speeds and hence is most useful in very high performance cars, aircraft and helicopters. Many NA engines today make use of Variable Length Intake Manifolds to harness Helmholtz resonance, which has a mild forced induction effect but is not considered true forced induction. Cylinder head porting design is of premium importance in naturally aspirated engines. Camshafts usually will be more "aggressive", having greater lift and duration. Also, cylinder head gaskets will be thinner, and with the top of the piston rising up into the combustion chamber, for high-performance NA engines that benefit from higher compression.

Naturally-aspirated engines generally gives less power than either turbo or supercharged engines of the same engine displacement and development level but tend to be cheaper to produce. In drag racing, naturally-aspirated vehicles are vehicles that do not operate with a blower, a turbo, nor use nitrous oxide.

Many racing series specify NA engines to limit power and speed. NASCAR, IndyCar, and Formula One are all in this category. Naturally-aspirated engines have been mandated in Formula One since 1989, in order to curb the excessive powers being developed by engines with superchargers or turbochargers.

Originally Posted by chung87

any one know how to get the front bumper off a 2007 2.5i impreza?? im tryin to install an injen cold air intake, dunno if that would increase the hp or not, injen installs directly to the factory air box but wanted to make sure that i wouldnt screw my self over if the cai ingested water or somethin well tahnks in advanced