Rear Exhaust Upgrades
for Improved Clearance and Power
(Range Rover III/L322/LM)
Introduction
Michael's Solution
More Information
Photo
at right: Michael's much smaller rear muffler in place on his TD6
Introduction
On most 4x4s, including the Mk III's predecessor and the Range Rover
Sport Supercharged, the exhaust tailpipes are the most vulnerable items
likely to be destroyed in real-life four wheeling. The Range Rover III
designers did a much better job than most in arranging the rear exhaust
tailpipes so they do not protrude at all from the underbelly. However,
the rear muffler is especially large and bulbous, and in real life four
wheeling the rear overhang is the most common ground contact area on
almost any vehicle. For those of us who use our Range Rovers for their
intended purpose, the huge rear muffler can be the limiting factor in
getting through certain obstacles like washouts and rocks. Michael
Quinn encountered such a problem on his Mk III Range Rover, and was
kind enough to share his solution with other owners.
Meanwhile, aftermarket exhaust systems for the Mk III have emerged. The
Borla system is mainly intended to increae power output by freeing up
exhaust flow, but a side effect is that the much smaller mufflers used
provide improved ground clearance for four wheeling. These systems are
also described bekow.
Michael's Solution
Michael reports "Just over a month ago I managed to tear
off the rear
muffler on my 2005 TD6 whilst out on some rocky trails. As you will see
in the pictures a much smaller muffler is used which offers significant
additional clearance to the rear of the vehicle".
Michael undertook a process of trial and error to design a replacement
muffler that would not drag on the ground. It took three successive
attempts to get the baffle combination right as the first two mufflers
where either too big or restricted engine performance. In fact, one led
to a noticeable increase in fuel consumption as well as reduced
performance.
Regarding his final design, Michael reports: "The one illustrated here
(above and at right) is very compact and is tucked up high against
the rear cargo floor where there is no likely chance of getting hung up
when off road. The engine breathes much more easily with even more
response when accelerating and better fuel economy. There is slightly
more noise from the smaller baffle but is not intrusive."
Michael thought his solution might be of interest to other owners if
they,
like us, enjoy the level of serious off roading of which the Range
Rover is capable.
Note on Petrol (Gasoline) Powered Range Rovers
It should be noted that the solution illustrated here is for a TD6
Range Rover which has only one exhaust pipe extending back to the rear
of the vehicle. The petrol/gasoline-powered V8 models have two pipes
(one from each cylinder bank) that reach ther rear muffler assembly
(note raised section of suspension member in photo above that is wide
enough for two pipes to pass under it).
Accordingly, for the V8 models a slighly different approach will be
needed, probaly utilizing two small mufflers in place of the stock huge
double mufffler assembly. If anyone has tried this, please email me so
we can share it with other owners.
Photo:
Stock V8 rear muffler showing its limiting effect on ground
clearance compared with Michael's unit above.
Borla Exhaust for RR III
One option for the V8 model is the new Borla exhaust that
has been
developed for it. Their replacements for the stock rear muffler
assembly (see bottom portion of picture at right) are much smaller than
the original, and therefore less likely to get hung up on rough
terrain.
The Borla system uses aircraft-quality T-304 stainless steel
construction (lighter
and stronger than conventional steel), and is fully welded without
crimping for
umimpeded flow-through. Slip-fit connectors provide an easy, secure
fit. Maintenance-free sound absorbing materials maintain low dB’s,
protects against burnout and reduce shell temperature.
These exhausts not only improve rear clearance but actually improve
engine
performance. They have a 1 million mile guarantee, and are legal in all
50 states. Cost is about $850.
Photo courtesy of Atlantic British
More Information
Borla exhaust upgrade
for RR III available from Atlantic British
