Exhaust question....

[Mr Roper]

Why do some diesel exhaust pipes point down and some don't?





I'm guessing the answer is obvious but in all my years of driving I've never thought to ask till now..

[HellDiver]

Some owners put Viagra in the tank?

[Mr Roper]

Is it to do with diesel engines more prone to drawing water in the event of flooding?

or

Avoids dirty great plumes of smoke being plastered over pedestrians?

or

did they realise that pointing down looks pants and changed it??

[anonymous-user]

It's an attempt to hide the soot! Early diesels (without DPF's) chuck out a lot of soot under hard accels at low rpms (in the "smoke limited" operation zone) so by having a downward pointing pipe, this soot tends to merge better with the black coloured road, and be less obvious (except at night, when the following cars headlamps easily highlight the "haze" )


More modern diesels with 1) better cal and higher injection pressures or 2) DFP's emit just about no soot, so they now tend to have straight tailpipes

[lescombes]

Mine had a "droop" chrome end when I got it on exhaust change I opted for a stainless version and straight out....nice for producing clouds of coal smoke when pushed mega hard...

[Mr Roper]

Thanks clearing that up MT