Engine Components

About Engine Components

These parts keep a modified engine alive rather than making it quicker. Catch cans for the direct injection engines that cake their own intake valves. Oil coolers for turbo cars that see track days. Radiators and thermostats for anything sitting in Arizona traffic in July. Mounts for the car that's gone sloppy in the shifter under power. Pick your car and this page keeps only what suits that engine.

A catch can sits in the crankcase vent line and grabs the oil vapor before it gets to the intake. On a port injected engine the fuel spray washes the valves and the can is a nice extra. On a direct injection engine nothing washes them, so the vapor bakes on and the can becomes maintenance. Empty it with the oil. Listings say whether a kit plugs in or whether you'll be cutting the factory lines.

Mounts are the part people buy too stiff and regret. An insert or a full urethane mount takes the slop out of the shifter and stops the engine rocking on a launch, and it pushes more vibration into the cabin at idle. A street insert is the middle road. Pulleys and throttle bodies are on this page too, and both want a tune before they'll show you anything.

Common questions

Do I need a catch can

On a direct injection engine it's the cheapest insurance you can buy. The valves never see fuel, so crankcase vapor bakes onto them as carbon and you're losing a little power every year. A can in the vent line catches most of that before it arrives. Port injected engine? The fuel washes those valves for you, so the can's optional.

Will stiffer mounts make the car vibrate

Yes, and how much depends on what you choose. A street insert adds a small buzz at idle that you stop hearing inside a week. A full urethane mount adds a buzz you notice at every light. A solid mount turns the cabin into a tuning fork. Pick the softest thing that fixes your problem, and for most cars that's the insert.

Is an oil cooler worth it on the street

On a turbo car that sees track days or an Arizona summer, yes. On a naturally aspirated commuter, no. Oil temperature climbs on long pulls and the turbo bearings live in that oil, so a cooler keeps it in range and the turbo alive. A thermostatic unit stays out of the way in winter, and it's worth the extra over a plain one.

Do I need a tune for a throttle body

Almost always. A bigger throttle body changes airflow at a given pedal position and the factory maps expect the original, so without a tune the car idles oddly and gains nothing for the trouble. With a tune the gain is small on a naturally aspirated engine and a bit more on a boosted one at full throttle. It's an end of build part.