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WHAT'S NEW
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| "Go anywhere,
do anything" |
Owning
a Jeep is a macho thing, so owners expect performance. |
And if it isn't a macho thing, owners still expect
performance: certainly enough performance to tow
a trailer with at least a quad or a couple of sports
bikes, at a decent pace. |
Well
the good news is that the development continues
unabated on an SAC conversion to meet these requirements. |
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Initial results show a significant performance
improvement, but fuel consumption and refinement
still needs to be improved, and the next R&D
phase is focussing on these areas. |
In independent
testing it achieved a 174 km/h top speed and manage
a 0 - 100 sprint in an impressive 12,3 seconds,
along with vastly improved overtaking ability. |
Another
plus is its ability to maintain a comfortable
cruising speed on the freeway, despite its brick-like
aerodynamics and gearing which is, quite frankly,
longer than ideal. |
Most of the additional 33 kW
which the 4,0 litre straight six produces comes
from bigger valves, a larger throttle body, revised
engine mapping, and a custom-built airbox. |
SAC's
engineers are looking at the entire exhaust systems
to unleash more power, and also the final drive
ratio to give it more suitable overall gearing
in the interests of better economy. |
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| A
Jeep disguised by Power |
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The
4.0L Wrangler models, that share a engine
with a few other Jeep's has been under the
development light at SAC.
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These vehicles have
been popular for conversions over the past
few years within the SAC group but given the
extremely long gearing the power increase
simply wasn't enough.
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Extensive
testing has been completed around the Air
Intake System and the Throttle body. We found
the vehicle to be very starved of air and
made some changes...
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| READ
MORE... |
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| "JEEPERS"
- A Wrangler that goes! |
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The
Jeep Wrangler is the archetypal compact sports utility
vehicle, but in the South African high altitude / high
ambient context its overall performance is impaired
by two shortcomings – both of which can be
addressed by tuning gurus, Steves Auto Clinic.
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A combination of absurdly
long gearing and a conservative, closed-loop engine
management system have resulted in poor acceleration
and excessive fuel consumption...
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MORE... |
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| Jeep Wrangler
- Wrangler buttoned up |
SAC
Holdings is putting the finishing touches to its
development programme with the Jeep Wrangler, a
vehicle which is growing in popularity thanks to
its strong fashion appeal. |
While it has been on
the market for a number of years, its success is
partly due to recent changes in specification level
and pricing. |
It
has been the subject of some development within
the SAC network in the past, but the benefits of
this have been hampered by excessively long gearing. |
More recent R&D has focussed
on the air intake system in general and throttle
body in particular. Holdings' engineers realised
the fundamental problem was air starvation and
designed an enlarged throttle body, measuring
63 mm. |
This made a huge improvement
leading to a prototype 73mm throttle body being
developed, along with an enlarged inlet duct between
the throttle body and a custom-made airbox enclosing
a high performance air filter. |
The 'stage one'
conversion was rounded off with a suitable exhaust
system, and then fine-tuned and mapped via a Unichip. |
The
Wrangler also benefited from some attention to
the cylinder head (bigger valves and an increased
compression ratio) and the final result was an
additional 33 kW. |
The vehicle now pulls the long
gearing more easily. |
Further development is underway
to change the rocker shaft ratios to enable the
enlarged intake and exhaust valves to open even
further. |
Watch
this space for a more detailed look at the Wrangler,
and driving impressions from Adrian Burford. |
This
will be followed up by a media publicity campaign,
including road tests by selected publications. |
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