HIGH PERFORMANCE 4X4 TOURING MODS

After a few years of driving, and a couple of hundred kilograms of added accessories later, your near-new 4X4 might not feel so new anymore. Luckily, when it comes to safely extracting every inch of capability from your engine, there are a handful of proven techniques guaranteed to put a smile on your dial. It doesn’t matter if your definition of performance is straight out brute power, better fuel economy or even a mixture of both. This 4X4 performance upgrade guide has your needs covered, as we showcase the best ways to motivate your 4X4.

WHEN YOU NEED IT

If you tow or carry big loads, we guarantee there has been at least one occasion where you would have gladly made a deal with the devil in exchange for more power. The same goes for long distance tourers who need to cover big kilometres through traction sapping slippery, sandy or steep terrain. Also, perhaps your older 4X4 is set up the way you like it, but has trouble keeping up with the latest and greatest 4X4 on the highway. Why sell a truck that works, simply because it could be improved in one area? It doesn’t matter what you drive, there is always a way to make it perform better.

WHEN YOU DON’T NEED IT

If you love heading into remote areas, the best advice is to keep engine modifications to a minimum for the sake of reliability. Tracking down aftermarket parts in the bush can require a university degree in logistics, where factory parts for popular makes and models are generally sourced over the counter in most major regional centres. Good maintenance will lead to better performance, which is far more important to reliable touring than a hot-rodded engine with horrible fuel economy. Find the balance, and ask yourself: what do you really want your vehicle to do?

DYNAMOMETER TUNING

Dyno tuning is the most accurate method of determining if your engine is performing to its potential. By running your 4X4 under simulated loads on a rolling road, specialised dyno tuners will be able to measure power production figures as well as the extremely important air-fuel ratio (AFR) readings; then optimise this mixture to suit your situation. You might be searching for a more conservative tune with better fuel economy on the highway or around town — or on the other end of the scale the maximum amount of power safely available. A chat with a reputable dyno specialist to determine your needs and expectations will be the best place to start. Also, a good practise is to have your 4X4 dyno tuned after any performance modification has been undertaken. This proves you are getting the most from the upgrade and that you aren’t potentially damaging your engine in the process.

PERFORMANCE CHIPS

The world of performance chips is filled with massive claims. Some manufacturers even claim gains of up to 35 per cent more power while delivering 10 per cent better fuel economy at the same time, all with just a simple plug-and-play install. Performance chips work in many different ways depending on the brand. Some work by increasing fuel rail pressure, others increase turbo boost, and some change injector pulse timing. Naturally, some chips are more advanced than others so it pays to do your research into which unit works best with your 4X4. Essentially, performance chips put more fuel into the engine while tricking management systems into accepting this new power increase. For best results, combine chips with a free-flowing exhaust and a few hours with an experienced dyno tuner. This will highlight any gains, as well as ensuring correct operating parameters for long lasting trouble free (powerful) motoring.

EXHAUST UPGRADES

Engines need to breathe to perform better. If you don’t understand this principle, imagine going for a jog with a sock in your mouth and see how far you get before running out of puff! By removing restrictions in your exhaust system, spent gasses can escape the combustion process quicker. What this means is more air and fuel can then enter, creating a bigger bang – simple, right? Take one look at the factory exhaust on your 4X4, and then an aftermarket exhaust system. It’s safe to say the difference in material quality, pipe diameter, bends and overall construction will be easy to spot. Most manufacturers claim better fuel economy and power gains of up to 10 per cent simply by fitting a mandrel bent, larger diameter exhaust. Oh, and don’t forget how much nicer a set of decent pipes will sound, too…

AFTERMARKET TURBO SYSTEMS

If you own a naturally-aspirated diesel engine, or a factory turbo-diesel there is one sure-fire way wake the sleeping beast inside. Aftermarket turbo systems fitted to a diesel engine can offer major increases in power and torque over stock. And just like the tyres and shock absorbers fitted to your 4X4 from the factory, the original turbo fitted may in fact not even be the most efficient item for your engine – it’s more likely to be the cheapest that would do the job. A turbo upgrade is a task best left to the professionals, as the results could be catastrophic if you get the tuning side of things wrong. With a well-tuned and correctly installed turbo however, you can expect increases in horsepower and torque from 15-40% depending on your make and model.

SNORKELS AND RAISED INTAKES

Fact: Engines love cold air. The cooler the air the denser it is, meaning more precious oxygen is available for the combustion process. Cold air keeps engine temperatures lower, meaning the vehicle will perform more efficiently. Cold air intakes are very common inclusions on performance cars, yet due to the nature of four-wheel driving they could cause more harm than good. Traditional cold air intakes are mouth-like scoops that sit low and forward of the engine to catch cool air – the exact opposite of what you want in a patch of bulldust or in a deep river crossing. This is where snorkels or raised air intakes (as some manufacturers prefer to call them) come into play, by providing cool and clean air for the engine to consume.

INTERCOOLERS

An often-overlooked component on factory turbo-diesels (or those of you with a naturally aspirated diesel with an aftermarket turbo) is the humble intercooler. An intercooler works by transmitting heat into the atmosphere, rather than into the engine’s intake. Think of an intercooler as a heat sink, designed to transfer heat from the warm turbo into cooler air perfect for combustion (remember, engines love cool air). The most common types of intercoolers are air-to-air and water-to-air, with air-to-air being favoured by most OEM suppliers and aftermarket systems, too. This drastically reduces running temperatures, in turn preventing engine failure. Another benefit of an intercooler is the ability to run more boost from the turbo thanks to these reduced intake temperatures.

MAINTENANCE

Just like an athlete, if your engine is out of shape, how can it be expected to perform at its peak? Basic things like advanced/retarded timing, loose throttle cables, dirty sensors, the wrong oil, or blocked injectors will rob you of valuable performance. Before you spend a cent on upgrades, it is imperative to ensure that what you have is working to its best potential. Anything else will just be a waste of time and money. You might just be surprised at how well your engine actually performs after a diet of healthy servicing.

ENGINE CONVERSIONS

Sometimes it’s easier, cheaper and just plain smarter to start from scratch, which is why engine conversions will always have their place in the 4X4 scene. Price up the cost on a rebuilt diesel engine versus what it would cost to drop in a fuel injected V8 and we dare say the conversion will start to look mighty appealing. In many cases it’s far more productive to start with an engine that already has the performance you crave right off the showroom floor, too. We have been seeing plenty of people putting Duramax turbo-diesel power plants into their Nissan Patrols and Toyota LandCruisers for example, and the same goes with the Chevy LS V8 range. The outcome? Let’s just say a few minutes watching engine conversion videos on YouTube will have you weak at the knees after you hear how good these weapons sound! Best of all, there are countless experienced specialists in the engine conversion field these days, so the performance of your dreams is just a swipe of the credit card away.

Words by Evan Spence