FAST’s Big Mouth Throttle Body Feeds Project Swedish Meatball

For the 5.3-liter LS engine in our Project Swedish Meatball, selecting the right throttle body was essential for our turbocharged LS engine combination. Fuel Air Spark Technology’s (FAST) 102mm Big Mouth Electronic Throttle Body is the ideal solution for handling high levels of boost for track outings while maintaining highway drivability and reliability. Designed specifically for GM LS engines, this throttle body provides greater airflow, better blade control, and improved safety features. To understand how it benefits our project Project Swedish Meatball and it goals, we’ll explore its key benefits, with insights from Mark Honsowetz, Product Manager for EFI at the Edelbrock Group.

The FAST 102mm Big Mouth throttle body’s larger diameter is crucial for increasing airflow. With a 102mm inlet, it flows significantly more air than the stock 90mm unit. This difference is particularly noticeable in turbocharged engines, where airflow restrictions can limit performance. As Honsowetz explains, “The larger 102mm diameter was engineered to provide increased airflow, supporting the demands of high-performance builds. In a boosted application, this difference is even more noticeable.” By eliminating the bottleneck that a smaller throttle body can cause, the FAST unit allows the turbocharged LS engine to reach its full power potential.

FAST’s design also addresses the inherent challenges of drive-by-wire (DBW) systems, which are common in modern vehicles but can create reliability issues in high-performance environments. The FAST throttle body includes an upgraded motor and dual return springs, which offer improved throttle response and added safety. “The dual return spring design offers additional safety and reliability, especially when dealing with higher loads in forced induction applications,” says Honsowetz. The dual springs ensure that if one spring fails, the other will maintain proper throttle control, making this feature crucial for high-stress applications like turbocharging.

A common issue with stock throttle bodies under high boost levels is throttle blade flutter, where the blade becomes unstable due to the increased pressure. This can lead to erratic performance and cause the ECU to enter limp mode. FAST solved this problem by using a reinforced shaft and rigid butterfly design to eliminate blade instability. “The critical aspect of this throttle body is blade control. Stock LS throttle bodies will flutter under high boost,…