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Exhaust flexible component existence

Exhaust flexible component existence

Exhaust flexible component existence

Hi All

I would like to know a history and the first time that the flexible componenet was used on the auto exhaust systems. seen that the old cars don't even have it , but you haven't seen probably many ruptures in the exhaust pipe, I was just curious to know its necessity of use

RE: Exhaust flexible component existence

The original Mini would certainly have benefited from one. As I remember they became common in the 80s, probably because exhaust systems suddenly got expensive as cats came in. There are two main types, spherical joints, and flexi hoses. The latter are better, and more expensive.


Greg Locock

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RE: Exhaust flexible component existence

Front wheel drive drove the push towards the corrugated hose type flex joints. Front wheel drive engines torque fore and aft which causes much more difficult to compensate for movement of the exhaust system. You still have to have a flex joint whether it's a hose type or spherical seat type unless you plan on using rigid motor mounts.

RE: Exhaust flexible component existence

Also if you look at older cars (60's) the first support of the exhaust system was nearly back to the muffler. There was a lot of pipe to flex, and combined with fairly rigid motor mounts and rear wheel drive everything worked.
Front wheel drive, and support for a closely mounted catalytic converter is an entirely different set of issues and compliance is needed.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

RE: Exhaust flexible component existence

I had a motorcycle that used bronze (I think) mesh inserts between all of the joints on a titanium exhaust system. It allowed for axial slip but it was a rigid mounted engine in a very rigid frame.

RE: Exhaust flexible component existence

Seems to me that flexible exhausts have been around since the invention of an internal combustion engine on wheels.


The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: Exhaust flexible component existence

The Mini sure needed a flex pipe - but BMC were onto it. The 1800 had a flex pipe, and needed it. I once welded one up solid in an emergency fix...and later the end of the exhaust manifold broke off. So the Austin 1800 was the first flex pipe I came across, although I think the Wolseley 6/110 had a couple too.

RE: Exhaust flexible component existence

The other issue with FWD is the torque applied to the motor-gearbox is typically 3 times that of a RWD. (assuming a 3:1 final drive)

je suis charlie

RE: Exhaust flexible component existence

Dgallup, that´s right! The other day I saw in my city a Citroen11, from 1930, and I was talking about this and other things about the engine and the transmission of the car with the owner

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