How do swirl flaps work

We have kits listed below for those. Home Blog Killer Swirl Flaps. What are Swirl Flaps? What do they do? Audi 2. Recent Posts. At low engine speeds, these valves are closed which causes air to swirl around the combustion unit and creates a better fuel-to-air ratio. However, the valves open almost fully above rpm or so, meaning their performance and emission benefits are moot at that point. The position of the valves is regulated by electrical actuators or mechanical vacuum actuators to create turbulence for better fuel-air mixing which reduces emissions and increases low-end power and torque.

This main purpose of using swirl flaps in the engines is to ensure the proper mixing of fuel and air at low speeds so by lengthening the route of air entering the cylinder head, swirling the air inside the combustion chamber. An improved fuel-air ratio decreases the emission of pollutants and increases the performance and fuel efficiency of your engine. It goes without saying, but this reduction in toxic emissions is better for your vehicle and the environment.

One of the strongest benefits of swirl flaps is the improved fuel efficiency caused by the better fuel-air ratio inside the combustion chamber. An optimized fuel-air ratio results in fewer exhaust gases and an improved MPG which will save you money in the long run.

Swirl flaps were first introduced in BMW diesel engines in the year and were installed inside the intake manifold, though they were blighted by a lot of mechanical failures. Between , BMW modified the design of their swirl flaps to combat issues with reliability, but they still suffered from a lot of issues like carbon build-up, mechanical failures, and leaks. BMW stopped using the swirl flaps in their engines at the end of and discontinued the flaps in most of their engines after With time, the seals of the flaps get damaged which results in air leaking from the inlet manifold, compromising the fuel-air ratio they are designed to improve.

This causes the engine to use a richer mix of fuel which compromises the efficiency of your engine. Swirl flaps, especially the early ones used in BMW engines, are very prone to wear and tear. The danger is that the screws that hold in place the rectangle valve over time can work themselves loose and fall out, this results in the swirl flap and bolts passing through your engine and potentially creating massive damage to your cylinder head, piston, engine block and turbo.

In BMW modified the swirl flaps and this should stop the risk of the swirl flap and bolts falling into the engine as the flaps are now plastic and the bolts have been removed. The solution for this problem is to fit some swirl flap blanking plugs, which means the entire swirl flap system can be removed and all the risk of failure.

The only drawbacks to this solution is slightly increased emissions on idle and at very low speeds, there should be little to no performance loss or fuel economy loss.