While plenty of automotive enthusiasts are all about carving corners at the local track days, it’s a special breed that leaves tarmac behind for the dusty trail ahead. If your chosen ride is of the four-wheelin’ variety, here’s how you can modify it to dominate the dirt and mud.
Handling The Terrain
Building a good offroad rig requires a very different focus than building a car for street performance. A screaming high-performance engine is of no use when your tires are spinning in the air because you’re stuck in deep sand or on top of a pointy rock. Instead, four wheelers are concerned with a whole different set of parameters. Ground clearance is key to getting over obstacles without getting stuck, and good articulation is key to keeping your wheels on the ground and pushing you forward in deep ruts and on crazy angles. You’ll also want plenty of low-down torque, and tyres that can grip up in all conditions without snagging a puncture. It’s a whole different ballgame, so read on!
While we’re currently in an era of comparatively low gas prices, the last few decades have seen much volatility in the oil market. This can hit the hip pocket hard, particularly for those driving thirstier vehicles. Thankfully, modifications can help squeeze a few extra miles out of each gallon of dinosaur juice if you know what you’re doing.
The art of striving for the best fuel economy is known as hypermiling, and involves a broad spectrum of tricks and techniques to get the most out of a drop of fuel. Let’s dive in to how you can build a more efficient cruiser for getting around town.
Step 1: Know Thine Enemy
The MPGuino is a great solution for monitoring fuel consumption in older cars without a trip computer.
If you want to improve your fuel economy, the first step is to measure it. Without accurate measurement, it’s impossible to quantify any gains made or optimise for the best performance. For those with modern cars, it’s likely that there’s already a trip computer built into the dash. Using this to track your fuel economy is the easiest solution. Instantaneous modes are useful to help improve driving habits, while average modes are great for determining the car’s economy over time.
However, many older vehicles don’t have such features installed as stock. Thankfully, there’s a few ways to work around this. For those driving post-1996 vehicles outfitted with an OBD-II port, tools like Kiwi or Scangauge can often track fuel economy. Failing this, most fuel injected cars can be fitted with a device like the MPGuino that monitors fuel injection to calculate consumption. Fundamentally, all of these tools involve tracking the amount of fuel used per distance travelled. Factory tools and OBD-II gauges do it by using the car’s standard hardware, while the MPGuino splices in to speedometer signals and injector triggers to do the same thing with an Arduino. If you do decide to install a custom device, make sure you calibrate it properly, else your figures won’t bear much resemblance to what’s going on in reality.
Of course, as long as your car has a working odometer and a fuel tank that doesn’t leak, there’s always the pen-and-paper method. Simply reset the trip odometer to zero after filling the tank to the brim. Then, when refilling the tank, fill all the way to the top, and divide the miles driven by the gallons of fuel added back to the tank. This isn’t the most accurate method, as the nature of gas station pumps and automotive fuel tanks mean that tanks aren’t always accurately filled to the brim, due to air pockets and devices used to prevent overfilling. Despite this, it’s a handy way of getting some ballpark figures of your car’s performance over time.
In 1960, Enzo Ferrari said “Aerodynamics are for people who can’t build engines”. It’s a quote that’s been proven laughably wrong in decades since. Aerodynamics are a key consideration for anyone serious about performance in almost any branch of motorsport. Today, we’ll take a look at how aero influences the performance of your car, and what modifications you might undertake to improve things.
Gains To Be Had
Improving the aerodynamics of your vehicle can mean wildly different things, depending on what your end goal is. Aerodynamics affects everything from top speed, to fuel economy, to grip, and optimizing for these different attributes can take wildly different routes. Often, it’s necessary to find a balance between several competing factors, as improvements in one area can often be detrimental in another.
To understand aerodynamics with regards to cars, we need to know about the forces of lift (or downforce), and drag. Drag is the force that acts against the direction of motion, slowing a vehicle down. Lift is the force generated perpendicular to the direction of motion. In the context of flight, the lift force is generated upwards with respect to gravity, lofting planes into the air. In an automotive context, we very much prefer to stay on the ground. Wings and aerodynamic surfaces on cars are created to create lift in the opposite direction, pushing the vehicle downwards and creating more grip. We refer to this “downwards lift” as downforce.
Whilst swapping out the stereo in his car for a more modern Android based solution, [Aaron] noticed that it only utilised a single CAN differential pair to communicate with the car as opposed to a whole bundle of wires employing analogue signalling. This is no surprise, as modern cars invariably use the CAN bus to establish communication between various peripherals and sensors.
In a series of videos, [Aaron] details how he used this opportunity to explore some of the nitty-gritty of CAN communication. In Part 1 he designs a cheap, custom CAN bus sniffer using an Arduino, a MCP2515 CAN controller and a CAN bus driver IC, demonstrating how this relatively simple hardware arrangement could be used along with open source software to decode some real CAN bus traffic. Part 2 of his series revolves around duping his Android stereo into various operational modes by sending the correct CAN packets.
These videos are a great way to learn some of the basic considerations associated with the various abstraction layers typically attributed to CAN. Once you’ve covered these, you can do some pretty interesting stuff, such as these dubious devices pulling a man-in-the-middle attack on your odometer! In the meantime, we would love to see a Part 3 on CAN hardware message filtering and masks [Aaron]!
While the car world is obsessed with everything boosted these days, many still yearn for the smooth power delivery and sonorous tone of a naturally aspirated engine. Of course, everyone still wants to go fast, so here’s how you go about getting more power out of your car without bolting on a big turbo or whining supercharger.
Intakes: This Can Get Pretty Invovled
A modified intake installed on a Honda S2000. Also referred to as “cold-air intakes”, they aim to suck in air at lower temperature which helps produce more power – hence the shield between the air filter and exhaust.
The intake is one of the first modifications made by many budding car enthusiasts. Throwing on a chromed intake pipe with a big pod filter was the mod to have back in the Fast and Furious era. Power gains can be had, though typically these are minor – on the order of 5-10 horsepower at most. It all depends on the car in question. A BMW M5 V10 was designed for high performance, with a highly advanced intake with individual throttle bodies from the factory. It’s unlikely any eBay parts are going to unlock horsepower that BMW’s engineers didn’t already find. Conversely, early Mazda Miatas are known to have a restrictive intake, largely due to the flap-type air flow meter. Replacing this with a freer-flowing setup has merit.
For those addicted to automotive thrills, there’s always an underlying lust for more power. For those chasing a bigger number, forced induction is one of the most effective ways to achieve it. In addition to more grunt, you get a whole bunch of fun new noises, too. For those with a naturally aspirated car, here’s how you go about converting to forced induction.
Superchargers and Turbos
When we talk about forced induction, we’re talking about forcing more air into the engine under pressure. With more air available, it’s possible to fully combust more fuel, creating more power. The two most common ways of doing this are supercharging and turbocharging. We’ll be using the common automotive vernacular here, so those eager to bicker about terminology from the early 20th century aircraft industry best do it in the comments. Continue reading “How To Get Into Cars: Forced Induction”→
Takata Corporation has become well known as a lesson in product safety, thanks to their deadly airbags which were installed in cars worldwide. Despite filing for bankruptcy in 2017, their shadow lingers on as the biggest product recall in history continues to grow ever larger. Over time, the story grows deeper, as investigators find new causes for concern and deaths continue to mount.
