General

Should I remove BMW swirl flaps?

Should I remove BMW swirl flaps?

While swirl flaps definitely sound great on paper – offering improved fuel efficiency with one small part – they caused a great deal of mechanical problems for BMW owners. If you want to extend the life of your car and enjoy all the benefits of your BMW performance exhaust, we recommend having your swirl flaps removed.

Is a swirl flap delete worth it?

This has the benefit of altering the torque output of the engine but mainly reducing the engine’s emissions at idle. In normal driving the swirl flaps are open, the shortest route, so by removing the complete flap there is little to no performance difference felt when driving the vehicle.

What do BMW swirl flaps do?

Swirl flaps are small butterfly valves located within the inlet manifold on modern diesel engines. They are designed to help regulate the fuel to air ratio and improve emissions at low engine speeds. At light engine loads the flaps close, causing the air to swirl into the combustion chamber.

What happens when swirl flaps fail?

When a swirl flap fails, the debris drops down into the engine, either sticking in the valve port and jamming it open, causing the piston to collide with the valve, or falls into the cylinder itself causing the piston, valves and head to become damaged.

What do swirl flaps do on a diesel engine?

Swirl flaps produce a swirl alongside the cylinder axle. They are used in diesel vehicles to improve the mixing of the fuel-air mixture at low engine speeds. For this purpose, the air is fed to each cylinder through two separate channels in the intake manifold. One of the two channels can be closed with a swirl flap.

Can you clean swirl flaps?

Cleaning your Intake Manifold and Swirl Flaps The moderately expensive alternative is to if possible manually clean them. Most mechanics will recommend this – Why? Because they’ll earn well from the extensive hours it takes to complete the job.

Should swirl flaps be open or closed?

One of the two channels can be closed with a swirl flap. This creates a swirling of the fresh air. Better mixing reduces fuel consumption and pollutant emission. At higher engine speeds and torques, the swirl flap is opened to achieve a better filling level.

What are swirl flaps Vauxhall?

A swirl flap is a small butterfly valve fitted to four-stroke internal combustion engines with at least two intake valves. It is installed inside or just before one of a cylinder’s two intake ports, allowing to throttle its intake port’s air flow, causing a swirl in the other intake port not fitted with a swirl flap.

What happened to the BMW swirl flaps?

BMW introduced a modified inlet manifold (with swirl flaps still fitted) trying to address this problem, the spindle of the valve is thicker and stronger, sadly this design is also prone to failure. BMW finally gave up on swirl flaps in late 2008.

What are swirl flaps?

Swirl flaps are one of BMW’s biggest design mistakes…. This causes 1000’s of owners throughout the world either very expensive repairs or even vehicles being written off. The flaps live in the inlet manifold of BMW diesel M47TU & M57TU engines (either 4 or 6 flaps depending on the amount of cylinders).

What happens when you replace the swirl flaps on a manifold?

The badly designed swirl flaps are removed and replaced with our billet modified blanks. The vacuum rail (that drives the swirl flaps) is then removed and blanked off. We refit the manifold using brand new inlet manifold gaskets (these are often over looked elsewhere).

What are the flaps in a diesel engine?

The flaps live in the inlet manifold of BMW diesel M47TU & M57TU engines (either 4 or 6 flaps depending on the amount of cylinders). These values are designed to create a swirl (hence the name) in the inlet manifold, this aids towards better combustion under light load.