Advances in technology are based on making life easier for the human race. In the import industry, most engineers think a laptop plugged into a programmable gizmo is the best way to simplify complex issues.
Sometimes this way of simplifying hard problems merely adds up to much more difficult dilemmas-which in turn leads to more time-consuming trouble shooting.
I, for one, am not ashamed to admit I don't know the difference between Windows 98 and the next computer program. So I think I speak for the rest of the industry when I say that getting rid of the simplicity of turning dials and flipping switches for the allure of pulling out a laptop and programming by punching numbers into Windows is a mistake. The same scenario can be found in fuel tuning with piggyback computers. Where most companies added features that lead to options and more options, that in turn lead to special functions, HKS went back to making fuel tuning simple.
HKS is proud to say that the AFR is the very first airflow meter correctional device in the industry with a built-in CPU. Unlike most piggyback fuel computers in the market, the HKS unit uses its CPU to calculate the accurate amount of air flowing into the engine. AFR is a piggyback fuel computer that is not only easy to install, but it is easy to program.
Variables that play a part in over-fueling with vehicles that run mass air and vein air meters are intercooler pipe leaks or cracks and routing of the aftermarket blow-off valve into the atmosphere. We understand the intimidating gush of air upon release of the throttle works all too well to warn potential prey, but in the long run, the factory ECU cannot register the loss of air in the system. Routing this unused air into the atmosphere can lead an engine to run on the rich side when decelerating.
This is primarily caused by the mass air meter registering air intake before the turbo in order to calculate the fuel delivery. The problem is that when an aftermarket blow-off valve is not routed back into the intake tract, the mass air meter cannot register the loss of air in the system caused by the valve. This can sometimes lead to stalling when decelerating as well as possible slow throttle response between shifting.
HKS has solved the over-fueling problem by adding an option called EIDS. With this function, vehicles that run mass air-type metering systems can still run aftermarket blow-off valves that can compensate for the over-fueling on deceleration. This function does not work with speed-density vehicles (i.e. vehicles that run map sensor systems) and can be shut off by flipping the third dip switch to the "off" position. The unit automatically programs itself.
Initial Set UpOn the back of the AFR, the user has the ability to adjust the dip switches to the desired setting, based on the type of intake air metering system. The unit works with speed density, vein air meters, mass airflow meters, and frequency type systems. By adjusting the dip switches, the AFR is able to adjust the fuel output safely to the type of metering system. Once the preprogramming is complete, the overall fuel tuning is done using the settings dial.
Most of the fuel tuning is achieved by using the gain knob. This is also used to scroll through the different features the AFR has to offer. Fuel tuning can be adjusted in 11 different zone that range from 650 to 8000 rpm. When most piggyback fuel computers utilize designated rpm points, the HKS unit allows you to adjust each of the 11-rpm points within 50-rpm increments to benefit the needs of the engine. For instance: If you needed more tuning from the 750 rpm zone, yet the first zone starts at 650, this zone can be selected and bumped up to a 750 rpm start zone. Once the rpm points are set, fuel tuning can begin and be adjusted from -50 percent to +50 percent in 1-percent increments. HKS states that the AFR can change a vehicle's air/fuel ratio by one full point.
Response function is also an available option that can help the throttle response of a vehicle. Just like the main fuel tuning, the response tuning can be adjusted to better the throttle response of the vehicle. This setting allows for up to six adjustable rpm points, allowing a plus or minus of 50 percent change per rpm increment.
Testing Our guinea pig tester is a 1991 Acura Integra LS equipped with a Japan-spec B16A engine. Bolt-on power adders include an AEM cold-air intake, DC header and Tanabe Racing Medallion exhaust. Baseline figures registered 139.1 hp and 102.3 lb-ft of torque. After some minor tweaking of the HKS Super AFR unit, horsepower rose to 140.5 and torque checked in at 103.2 lb-ft of torque. In some areas of the dyno curve, power jumped by as much as 2-3 hp, which is good, considering the mild nature of the engine mods. Power can be unveiled with use of the HKS AFR but the quality of the tuner is key to making safe power.
Affordable, simple and programming friendly; that's the performance of the HKS AFR. No data logging or programming by laptop, just simple fuel tuning made easy. This affordable unit show thats that all the bells and whistles that come with most fuel tuning computers don't necessarily make them the best. Having a reliable and easy-to-use piggyback CPU can sometimes be the fastest and most trouble-free way to address these some times difficult situations.