Visit Steves Auto Clinic for the best performance upgrades, performance chips

It isn’t often that you get good, cheap horsepower out of a modern engine, but that is exactly what SAC has managed to achieve with an aftermarket upgrade to the 4,0-litre V6 powerplant in the Nissan Navara.
The conversion is available through the network of 12 Steves Auto Clinic franchise stores nationwide. For this you get approximately 20 kW more than standard, but, importantly, there is no loss of refinement. And to prove that it is possible to have your cake and eat it, the upgrade returns improved fuel consumption in normal driving.
The conversion comprises a stainless steel SAC designed free-flow exhaust system mated to tubular manifolds from SAC partner, Wildcat. The focus of the research and development leading up to the introduction of this conversion has been to improve the exhaust gas-flow characteristics but without a significant change in noise level or tone when cruising.
A minor change is also made to the airbox which houses the air filter. A turned aluminium venturi is fitted into the front face of the airbox, which has the effect of ramming cooler air into the engine as road speed increases
But with modern engines there is little to be gained by just changing the inlet and exhaust. So that maximum benefits can be realised, a Unichip piggy-back computer module has been fitted, with a pre-programmed ‘map’ of optimised ignition and fuel parameters. This matrix of electronic values allows the engine to achieve its peak efficiency across the entire engine speed range, which means the idle quality is unaffected, while the maximum usable rpm is unchanged at 6 300. The true top speed, as tested independently at Gauteng altitude remains at 191 km/h – though the limiter can also be removed on a customer’s insistence.
Overall driveability has been noted as one of the V6 Navara’s strong points in standard form – but that doesn’t mean it can’t be improved on significantly. Just over a second is lopped off the 60 – 100 km/h time in fourth gear, while the modded car is a full 1,7 seconds quicker between 80 and 120 km/h in fifth gear. Those who plan on towing with their Navara should rejoice in these numbers; translating as they do into far less effort (and more safety) whether it comes to overtaking, or simply maintaining a constant speed when cruising.
While the conversion isn’t intended to turn the Navara into a robot racer, there are significant gains in standing start acceleration too. According to before and after results provided by testing experts, Roadworx, the Navara will sprint to 100 km/h in a fraction under nine seconds, and cover the standing kilometre in 29.76 seconds at a terminal speed of 178.1 km/h. A sub-30 second kilometre sprint is considered good for a conventional passenger car at power-sapping Reef altitude – never mind a four-wheel-drive double cab with an open ‘bak’.
The Navara has become hugely popular in a short space of time, and no doubt there will be plenty of owner’s of this archetypal man’s ‘truck’ who will appreciate the extra grunt of the SAC conversion whether they’re towing with it or not. With the bolt-on nature of this kit (no internal changes are made to the engine), owners can drop their car off at an SAC outlet in the morning, and drive out that same afternoon with a vehicle which feels much more satisfying in all kinds of driving conditions. The conversion can be successfully applied to all V6 Navaras; both two and four-wheel-drive, and with automatic or manual transmission.

Performance data, SAC Navara 4.0 V6 (M) versus standard

SAC Standard
0 – 60 km/h: 4 4.38
0 – 80 km/h: 6 6.63
0 – 100 km/h: 8.98 9.84
0 – 120 km/h: 12.1 13.42
0 — 400 M (seconds): 16.34 16.88
SPEED: 138.8 134.4
0 — 1000 M (seconds): 29.76 30.81
SPEED: 178.1 171.9
VMAX: 191 191
60 – 100 KM/H (4th): 7.73 8.85
80 – 120 KM/H (5th): 10.99 12.69