Automotive Boost Gauges
Boost gauges for cars and trucks are designed to show you how many PSI or BAR a car is seeing at the intake manifold. Knowing how much boost your behicle is making will make it easy to ensure that your car is not developing too much boost, which can lead to a lean condition inside the engine. Most vehicles that are equipped with turbochargers from the factory do not come with boost gauges, as OEM manufacturers anticipate that most of their customer's would not know what the boost gauge meant in the first place. A few manufacturers have included standard boost gauges in their vehicles, however standard boost gauges tend to be innacurate at the best of times, and downright wrong most of the time.
Sensing a need for enthusiasts to keep tabs on what their cars are doing at all times, the automotive aftermarket has stepped up to the plate to offer a huge variet of aftermarket gauges and meters. While there are many types of gauges made by many manufacturers, this article will focus only on boost gauges made by the more reputible gauge makers. The companies featured are for the most part either Japanese or American, as gauges made in other countries tend to be low quality, and will often read incorrectly. It is not uncommon for a cheap gauge to be as much as two or three PSI away from actual boost pressures.
Trust/Greddy Boost Gauge
Trust/Greddy is a company that produces a huge array of aftermarket parts. One of their best products are their line of highly accurate gauges. In this case, the Trust boost gauge (shown on the right, measuring boost in BAR), is an easy to read, high-tech gauge with both peak-boost and warning features. If a preset boost level is passed, a red light will shine, and the gauge will make an audible beeping noise to warn the driver.
Trust/Greddy gauges come in either white or black, and are widely reguarded as one of the easiest gauges to read on the market, as well as being accepted as one of the most accurate series of gauges available.
Stri has recently surfaced and quickly become popular with their line of highly accurate, easy to read gauges. Available in both PSI and BAR, Stri gauges feature advanced peak boost recording and playback, as well as an advanced overboost warning system. Stri is quickly becoming very well respected among the Japanese manufacturers due to the quality of their lines of gauges.
HKS is one of the most famous Japanese big-gun companies, having been around for 40-someodd years. They produce everything from camshafts to turbochargers, as well as a line of gauges. HKS gauges aren't as common, as most reguard them as more difficult to read than Trust or Defi gauges. While they may not be as visually appealing or easy to read, they are certainly just as accurate as the other Japanese gauges, telling the driver the exact readings with very little error margin.
AEM Tru Boost Gauge
AEM is known for their highly accurate, responsive digital gauges. The AEM Tru Boost gauge servers as both a boost gauge as well as a boost controller. Setting it up is simple enough, and it makes things easier, as both the boost controller and gauge are incorporated into one item, removing the need for multiple purchases. You can set a target boost level and the gauge will target that level, both for actual boost pressure, and boost pressure displayed on the gauge.
Blitz Boost Gauges
Blitz is known as a producer of various aftermarket parts, and their gauges have certainly earned a reputation for being accurate. When it comes to a Blitz boost gauge, you're either going to love it, or you're going to hate it. There's no in-between with these gauges. The design is incredibly attractive and easy to read for some, but ugly as sin and impossible to read for others. Reguardless of attractiveness, the Blitz gauges are reguarded as being very, very accurate.
Defi Boost Gauge
I decided to save Defi till last. Defi gauges are incredibly expensive, very, very easy to read, and are arguably the most accurate aftermarket gauges that are readily available. If a Defi boost gauge tells you that you're producing exactly 1 bar (14.7PSI) of boost pressure, then your car is producing exactly 1 bar of boost. Known for their incredibly accurate readings, attractive and easy-to-integrate designs, and long, long life spans, Defi gauges are arguable the best gauges produced by any of the big Japanese companies.
If you plan on picking up a full line of Defi gauges for your car, anticipate spending over $1,000 easily, as the gauges sensors and mechanisms are accurate and heavy-duty, thus driving the production cost of the gauges through the roof. As a result, you're going to be paying a lot for them, but it will be money well spent, as they'll probably outlast the car.
Autometer Boost Gauges
Autometer is an American company known for their vast quantity of automotive meter lines. They arguably have the largest gauge catalog out of any aftermarket company. Many people question the quality of Autometer compared to the Japanese companies, because the Autometer gauges tend to be much cheaper to purchase. If you're worried about accuracy, don't be. More racing series than I care to count use autometer gauges as standard equipment. If it's good enough for multi-million dollar race cars, it's good enough for your street car.
If you plan on buying an Autometer boost gauge, there's seemingly endless choices, looks, sizes, and shapes to chose from. At the end of the day, the widesweep gauges will always be easier to read than the shortsweep gauges, and they'll all be very, very accurate.