Figure 44. Exhaust system:
1 - bracket for mounting the inlet pipe; 2 - gasket; 3 - intake pipe; 4 - clamps for connecting muffler pipes; 5 - muffler suspension cushions; 6 additional muffler; 7 - main muffler.
The loss of engine power due to exhaust gases released through the exhaust system is approximately 4%.
The exhaust manifold is made of cast iron and is attached to the cylinder head studs. A ferronite gasket is used to seal the exhaust manifold and cylinder head. On the bottom side, the manifold has four studs for attaching the inlet pipe 3.
The intake pipe consists of a flange, two pipes and a gas receiver welded from two stamped halves and closed on both sides with asbestos heat-insulating gaskets and thin-walled casings. The intake pipe is made of stainless steel and has increased corrosion resistance. The intake pipe is attached to the studs of the exhaust manifold with self-locking disposable nuts. To eliminate vibration and increase rigidity, the intake pipe is additionally attached to bracket 1 of the engine cylinder block. A sealing gasket 2 made of asbestos reinforced with steel perforated tape is installed between the flange of the intake pipe and the exhaust manifold.
Additional 6 and main 7 mufflers consist of housings, perforated pipes and partitions. The main muffler is made of stainless steel for better corrosion resistance and has no welding points. All muffler parts are joined together by rolling. The additional muffler is made of steel, plated with aluminum 50 microns thick.
The mufflers allow to reduce noise up to 78 dB. The main muffler has five chambers for suppressing noise of a certain range of medium-high frequencies, the additional one has three chambers for suppressing high-frequency noise.
For thermal insulation and noise reduction, sheet asbestos or other insulating material is used between the housing and the protective casing of the additional muffler from above.
The mufflers and the intake pipe are connected to each other with clamps 4 through sealing rings made of sintered powder steel. Clamps with sealing rings significantly facilitate the removal and installation of mufflers. The mufflers are suspended on the body brackets on five rubber cushions 5 of the exhaust system suspension.
The exhaust system of the VAZ-21081 differs in the design of the exhaust manifold and the inlet pipe. The car is equipped with an exhaust manifold with one outlet and, therefore, the inlet pipe of the mufflers has one pipeline. The design of the bracket and the clamp for fastening the inlet pipe to the engine cylinder block has also been changed.