All cars are standard fitted with an exhaust (duh). These exhausts are not designed for the best performance, therefore it is possible to fit your car with another exhaust which gives just that bit extra power and that sound of a fast
In a sport exhaust, the fumes are directed in a straight line, in the backbox there are perforated holes and around it there is a soft and heat-resistant material. Exhaust fumes can be directed without any obstructions (best performance), these exhaust need not make any more noise then an original exhaust. It is wrong to think that car that produce a lot of noise will perform
|Regarding manifolds, it is an area a lot of people, including manufacturers seem to neglect, as most exhaust manifolds resemble those they fitted 30 years ago. The main reason here appears to be cost. It is far easier and cheaper to produce a compact cast iron manifold than it is to fabricate a tubular 4-branch manifold that has to be hand built. Quite useful gains can be made with a custom-built exhaust manifold, even on a standard road
All modern cars are emission controlled, one part of equipment to do this being a catalyctic converter, which is a box on the exhaust, similar in appearance to a normal silencer. This consists of a honeycomb of small passageways through which the exhaust gases pass, which forms a chemical reaction with the coating on the inside of honeycomb, to clean up the emissions. This method of forcing the exhaust gas through small passageways causes backpressure and restricts the engines performance. The solution is obvious, you remove the CAT and insert a plain pipe to bridge the gap between the pipes the CAT connected. On most cars removing the CAT will improve power by between 7% to 12%, and the cost for such a solution is usually about £60, where else can you get such an improvement for so little
The only problem that will occur is that it will not pass an M.O.T. To get around this you just keep the CAT in your garage and refit it for the test, which is simple
and at most only takes about half an hour to change.
Looks are massively important - who wants last year's design?
Not us. Stainless steel square-ovals are trick now, as they make
your car look like it's got a bigger than stock motor. But beware,
if you've got a bodykit room can be limited.
As a rule of thumb the size of the silencer box, not the
tailpipe, governs the sound of the exhaust. A larger silencer will
probaly be quiter than a smaller one, although the internal design
makes a major difference.
Most back boxes come with a new correct-sized clamp. If not,
you've got the hassle and the extra cost (a few pounds) of getting
them from a car spare shop.
Neat welds around the tailpipes and hangers
are what you want. Untidy welds can point to poor
construction, which in turn can lead to a short life (even
on stainless steel boxes)
These must be in the same position as the factory box for
easy fitting. Beefy welds mean the hangers aren't likely to
come loose in time
Doesn't rust but is more brittle than mild steel.
Lowgrade stainless steel exhaust systems can crack easily due to
the constant engine vibration.
||A simple piece of pipe that replaces the catalytic
converter. Fitting this device can increase power.
||The pipe connecting the manifold to the exhaust
||Metal Inert Gas welding is a relatively simple
process where a wire fed from a reel is electrically charged and
creates a join between two sections of steel while gas is pumped
around to keep the join clean.
||Tungsten Inert Gas welding is a high quality yet
more tricky process than MIG welding. An electrical arc is used
to heat the metal unit it melts and creates a permanent join.
TIG welds often look like fish scaling.
||Used to connect stainless steel systems, which
have a tendacy to be brittle, flexi-joints help soak up knock
and bumps which could otherwise cause cracks.