Evolution is the gradual development of something from a simple to a more complex form over time. Much like the fish that first scraped their way from the primordial ooze to eventually develop into the complex creatures that we are today, the Supra also had humble beginnings. Starting as just a sportier trim level on the Celica, the Supra has grown to fit into its rightful spot in the automotive food chain. Even today, the Supra is still adapting to its environment and developing a better breathing apparatus.
Unlike those prehistoric fish, we have technology on our side to reduce the evolutionary process from a few million years to a few million seconds. Ye gets the design process started by extracting the stock air intake from our Supra for a combination of initial tasks, with the first being our flow bench testing.
Studying the flow of the stock kit is essential so Ye can hone in on the areas that pose the most resistance. Our flow bench uses a vacuum to pull a calibrated amount of air, measured in cubic feet per minute (CFM), through the kit, and calculates the pressure drop from the inlet of the kit (atmosphere) to the bench, measured in inH20. Since the B58’s turbo isn’t pulling the same amount of air at all times, this test is performed at varying levels of CFM to simulate the full range of the engine’s potential. After pouring through the results, Ye was able to determine that the upper airbox lid and the corrugated section of the tube caused the most restriction when it came to air induction for the Supra’s B58.
Armed with the knowledge of the detailed performance of the stock intake kit, the Faro Design ScanArm comes into play. Using this arm, Ye creates a virtual model of both the stock intake kit, along with the available space in the engine bay for precise visualization of the building envelope. Once loaded into Solidworks, Ye can develop a freer-flowing intake kit, with a tangible representation being pulled from our 3D printers in a matter of days.
Since improving flow is one of the main objectives, the airbox needed a serious overhaul. If you look back at our review of the stock components, you’ll see that most of the available space was occupied by a large resonating chamber to keep intake noise to a minimum. The revised design removes the noise-canceling growth on the box for a much more direct path for a greater volume of air to enter the engine, with the added benefit of a more turbocharged soundtrack. While this prototype is created with PLA, cross-linked polyethylene (XLPE) plastic will be the construction of choice for our final production kit. Utilizing this material allows us to utilize a rotational molding manufacturing process which opens up the possibilities for unique shapes and designs.
Having the correct filter is the next step in the process of improving the flow through the intake. Panel filters are used in the production line since they’re cost-effective and provide the right amount of protection but can be a bit stuffy. High flow panel filters are an option, but when the box is one of the main culprits of flow restriction, a cone filter is the best fit. Given the size and shape of our box, we needed a very specific size when it came to our prototype. To top off our filter and airbox design, Ye is planning on including a large rubber grommet to fully seal the box and rest of the kit together.
With the filter fabricated and the airbox taking shape, the last item of business is the secure connection from turbo to the fresh air supply, starting with the tubing. The corrugated section of the stock system offers an uneven surface that can leave the fresh air tumbling over itself and reducing flow. Ye is instead opting for a three-piece connection from box to turbo. First, the main section of tubing, which will also utilize the same roto-molding process. Since the Supra is operating on a speed density tune, there’s no need to work around a perfectly calibrated MAF housing and this tubing can be adjusted to any size we need. The smooth interior of this design eliminates any inconsistencies in shape for a smooth flow to the turbo inlet.
When it comes to securing the intake to the turbo, the BMW and Toyota engineers favored a quick disconnect, which Ye plans on retaining. To ensure that our connection to the turbo is just as strong, if not stronger, with a CNC-machined aluminum quick disconnect section. We plan on using a short silicone coupler to mate the plastic and aluminum sections for both strength and retaining flexibility.
Evolution is a process. While our means of upgrading the A90 Supra’s intake system is a vastly accelerated one, there are still more forms that this kit needs to take before it can truly evolve. Coming in the next few weeks we’ll have our first look at the production sample, so stay tuned! Make sure to check out our other Supra products also in the works in the meantime.
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